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V3.14 s5p6442 #1

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V3.14 s5p6442 #1

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@moikop moikop commented Jan 8, 2014

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… regulator

This patch removes the voltage field from platform data of the atmel_mxt_ts driver and replaces it with regulator support.
…Tree

This patch adds support for Device Tree-based instantation to the atmel_mxt_ts driver.
tom3q pushed a commit that referenced this pull request Jan 11, 2014
The user has the option of disabling the platform driver:
00:02.0 Unassigned class [ff80]: XenSource, Inc. Xen Platform Device (rev 01)

which is used to unplug the emulated drivers (IDE, Realtek 8169, etc)
and allow the PV drivers to take over. If the user wishes
to disable that they can set:

  xen_platform_pci=0
  (in the guest config file)

or
  xen_emul_unplug=never
  (on the Linux command line)

except it does not work properly. The PV drivers still try to
load and since the Xen platform driver is not run - and it
has not initialized the grant tables, most of the PV drivers
stumble upon:

input: Xen Virtual Keyboard as /devices/virtual/input/input5
input: Xen Virtual Pointer as /devices/virtual/input/input6M
------------[ cut here ]------------
kernel BUG at /home/konrad/ssd/konrad/linux/drivers/xen/grant-table.c:1206!
invalid opcode: 0000 [#1] SMP
Modules linked in: xen_kbdfront(+) xenfs xen_privcmd
CPU: 6 PID: 1389 Comm: modprobe Not tainted 3.13.0-rc1upstream-00021-ga6c892b-dirty #1
Hardware name: Xen HVM domU, BIOS 4.4-unstable 11/26/2013
RIP: 0010:[<ffffffff813ddc40>]  [<ffffffff813ddc40>] get_free_entries+0x2e0/0x300
Call Trace:
 [<ffffffff8150d9a3>] ? evdev_connect+0x1e3/0x240
 [<ffffffff813ddd0e>] gnttab_grant_foreign_access+0x2e/0x70
 [<ffffffffa0010081>] xenkbd_connect_backend+0x41/0x290 [xen_kbdfront]
 [<ffffffffa0010a12>] xenkbd_probe+0x2f2/0x324 [xen_kbdfront]
 [<ffffffff813e5757>] xenbus_dev_probe+0x77/0x130
 [<ffffffff813e7217>] xenbus_frontend_dev_probe+0x47/0x50
 [<ffffffff8145e9a9>] driver_probe_device+0x89/0x230
 [<ffffffff8145ebeb>] __driver_attach+0x9b/0xa0
 [<ffffffff8145eb50>] ? driver_probe_device+0x230/0x230
 [<ffffffff8145eb50>] ? driver_probe_device+0x230/0x230
 [<ffffffff8145cf1c>] bus_for_each_dev+0x8c/0xb0
 [<ffffffff8145e7d9>] driver_attach+0x19/0x20
 [<ffffffff8145e260>] bus_add_driver+0x1a0/0x220
 [<ffffffff8145f1ff>] driver_register+0x5f/0xf0
 [<ffffffff813e55c5>] xenbus_register_driver_common+0x15/0x20
 [<ffffffff813e76b3>] xenbus_register_frontend+0x23/0x40
 [<ffffffffa0015000>] ? 0xffffffffa0014fff
 [<ffffffffa001502b>] xenkbd_init+0x2b/0x1000 [xen_kbdfront]
 [<ffffffff81002049>] do_one_initcall+0x49/0x170

.. snip..

which is hardly nice. This patch fixes this by having each
PV driver check for:
 - if running in PV, then it is fine to execute (as that is their
   native environment).
 - if running in HVM, check if user wanted 'xen_emul_unplug=never',
   in which case bail out and don't load any PV drivers.
 - if running in HVM, and if PCI device 5853:0001 (xen_platform_pci)
   does not exist, then bail out and not load PV drivers.
 - (v2) if running in HVM, and if the user wanted 'xen_emul_unplug=ide-disks',
   then bail out for all PV devices _except_ the block one.
   Ditto for the network one ('nics').
 - (v2) if running in HVM, and if the user wanted 'xen_emul_unplug=unnecessary'
   then load block PV driver, and also setup the legacy IDE paths.
   In (v3) make it actually load PV drivers.

Reported-by: Sander Eikelenboom <[email protected]
Reported-by: Anthony PERARD <[email protected]>
Reported-and-Tested-by: Fabio Fantoni <[email protected]>
Signed-off-by: Konrad Rzeszutek Wilk <[email protected]>
[v2: Add extra logic to handle the myrid ways 'xen_emul_unplug'
can be used per Ian and Stefano suggestion]
[v3: Make the unnecessary case work properly]
[v4: s/disks/ide-disks/ spotted by Fabio]
Reviewed-by: Stefano Stabellini <[email protected]>
Acked-by: Bjorn Helgaas <[email protected]> [for PCI parts]
CC: [email protected]
tom3q pushed a commit that referenced this pull request Jan 11, 2014
Even if user doesn't supply the physical netdev to attach vxlan dev
to, and at the same time user want to vxlan sit top of IPv6, mark
vxlan_dev flags with VXLAN_F_IPV6 to create IPv6 based socket.
Otherwise kernel crashes safely every time spitting below messages,

Steps to reproduce:
ip link add vxlan0 type vxlan id 42 group ff0e::110
ip link set vxlan0 up

[   62.656266] BUG: unable to handle kernel NULL pointer dereference[   62.656320] ip (3008) used greatest stack depth: 3912 bytes left
 at 0000000000000046
[   62.656423] IP: [<ffffffff816d822d>] ip6_route_output+0xbd/0xe0
[   62.656525] PGD 2c966067 PUD 2c9a2067 PMD 0
[   62.656674] Oops: 0000 [#1] SMP
[   62.656781] Modules linked in: vxlan netconsole deflate zlib_deflate af_key
[   62.657083] CPU: 1 PID: 2128 Comm: whoopsie Not tainted 3.12.0+ torvalds#182
[   62.657083] Hardware name: innotek GmbH VirtualBox, BIOS VirtualBox 12/01/2006
[   62.657083] task: ffff88002e2335d0 ti: ffff88002c94c000 task.ti: ffff88002c94c000
[   62.657083] RIP: 0010:[<ffffffff816d822d>]  [<ffffffff816d822d>] ip6_route_output+0xbd/0xe0
[   62.657083] RSP: 0000:ffff88002fd038f8  EFLAGS: 00210296
[   62.657083] RAX: 0000000000000000 RBX: ffff88002fd039e0 RCX: 0000000000000000
[   62.657083] RDX: ffff88002fd0eb68 RSI: ffff88002fd0d278 RDI: ffff88002fd0d278
[   62.657083] RBP: ffff88002fd03918 R08: 0000000002000000 R09: 0000000000000000
[   62.657083] R10: 00000000000001ff R11: 0000000000000000 R12: 0000000000000001
[   62.657083] R13: ffff88002d96b480 R14: ffffffff81c8e2c0 R15: 0000000000000001
[   62.657083] FS:  0000000000000000(0000) GS:ffff88002fd00000(0063) knlGS:00000000f693b740
[   62.657083] CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
[   62.657083] CR2: 0000000000000046 CR3: 000000002c9d2000 CR4: 00000000000006e0
[   62.657083] Stack:
[   62.657083]  ffff88002fd03a40 ffffffff81c8e2c0 ffff88002fd039e0 ffff88002d96b480
[   62.657083]  ffff88002fd03958 ffffffff816cac8b ffff880019277cc0 ffff8800192b5d00
[   62.657083]  ffff88002d5bc000 ffff880019277cc0 0000000000001821 0000000000000001
[   62.657083] Call Trace:
[   62.657083]  <IRQ>
[   62.657083]  [<ffffffff816cac8b>] ip6_dst_lookup_tail+0xdb/0xf0
[   62.657083]  [<ffffffff816caea0>] ip6_dst_lookup+0x10/0x20
[   62.657083]  [<ffffffffa0020c13>] vxlan_xmit_one+0x193/0x9c0 [vxlan]
[   62.657083]  [<ffffffff8137b3b7>] ? account+0xc7/0x1f0
[   62.657083]  [<ffffffffa0021513>] vxlan_xmit+0xd3/0x400 [vxlan]
[   62.657083]  [<ffffffff8161390d>] dev_hard_start_xmit+0x49d/0x5e0
[   62.657083]  [<ffffffff81613d29>] dev_queue_xmit+0x2d9/0x480
[   62.657083]  [<ffffffff817cb854>] ? _raw_write_unlock_bh+0x14/0x20
[   62.657083]  [<ffffffff81630565>] ? eth_header+0x35/0xe0
[   62.657083]  [<ffffffff8161bc5e>] neigh_resolve_output+0x11e/0x1e0
[   62.657083]  [<ffffffff816ce0e0>] ? ip6_fragment+0xad0/0xad0
[   62.657083]  [<ffffffff816cb465>] ip6_finish_output2+0x2f5/0x470
[   62.657083]  [<ffffffff816ce166>] ip6_finish_output+0x86/0xc0
[   62.657083]  [<ffffffff816ce218>] ip6_output+0x78/0xb0
[   62.657083]  [<ffffffff816eadd6>] mld_sendpack+0x256/0x2a0
[   62.657083]  [<ffffffff816ebd8c>] mld_ifc_timer_expire+0x17c/0x290
[   62.657083]  [<ffffffff816ebc10>] ? igmp6_timer_handler+0x80/0x80
[   62.657083]  [<ffffffff816ebc10>] ? igmp6_timer_handler+0x80/0x80
[   62.657083]  [<ffffffff81051065>] call_timer_fn+0x45/0x150
[   62.657083]  [<ffffffff816ebc10>] ? igmp6_timer_handler+0x80/0x80
[   62.657083]  [<ffffffff81052353>] run_timer_softirq+0x1f3/0x2a0
[   62.657083]  [<ffffffff8102dfd8>] ? lapic_next_event+0x18/0x20
[   62.657083]  [<ffffffff8109e36f>] ? clockevents_program_event+0x6f/0x110
[   62.657083]  [<ffffffff8104a2f6>] __do_softirq+0xd6/0x2b0
[   62.657083]  [<ffffffff8104a75e>] irq_exit+0x7e/0xa0
[   62.657083]  [<ffffffff8102ea15>] smp_apic_timer_interrupt+0x45/0x60
[   62.657083]  [<ffffffff817d3eca>] apic_timer_interrupt+0x6a/0x70
[   62.657083]  <EOI>
[   62.657083]  [<ffffffff817d4a35>] ? sysenter_dispatch+0x7/0x1a
[   62.657083] Code: 4d 8b 85 a8 02 00 00 4c 89 e9 ba 03 04 00 00 48 c7 c6 c0 be 8d 81 48 c7 c7 48 35 a3 81 31 c0 e8 db 68 0e 00 49 8b 85 a8 02 00 00 <0f> b6 40 46 c0 e8 05 0f b6 c0 c1 e0 03 41 09 c4 e9 77 ff ff ff
[   62.657083] RIP  [<ffffffff816d822d>] ip6_route_output+0xbd/0xe0
[   62.657083]  RSP <ffff88002fd038f8>
[   62.657083] CR2: 0000000000000046
[   62.657083] ---[ end trace ba8a9583d7cd1934 ]---
[   62.657083] Kernel panic - not syncing: Fatal exception in interrupt

Signed-off-by: Fan Du <[email protected]>
Reported-by: Ryan Whelan <[email protected]>
Acked-by: Cong Wang <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
tom3q pushed a commit that referenced this pull request Jan 11, 2014
When disconnecting it is possible that the l2cap_conn pointer is already
NULL when bt_6lowpan_del_conn() is entered. Looking at l2cap_conn_del
also verifies this as there's a NULL check there too. This patch adds
the missing NULL check without which the following bug may occur:

BUG: unable to handle kernel NULL pointer dereference at   (null)
IP: [<c131e9c7>] bt_6lowpan_del_conn+0x19/0x12a
*pde = 00000000
Oops: 0000 [#1] SMP
CPU: 1 PID: 52 Comm: kworker/u5:1 Not tainted 3.12.0+ torvalds#196
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
Workqueue: hci0 hci_rx_work
task: f6259b00 ti: f48c0000 task.ti: f48c0000
EIP: 0060:[<c131e9c7>] EFLAGS: 00010282 CPU: 1
EIP is at bt_6lowpan_del_conn+0x19/0x12a
EAX: 00000000 EBX: ef094e10 ECX: 00000000 EDX: 00000016
ESI: 00000000 EDI: f48c1e60 EBP: f48c1e50 ESP: f48c1e34
 DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
CR0: 8005003b CR2: 00000000 CR3: 30c65000 CR4: 00000690
Stack:
 f4d38000 00000000 f4d38000 00000002 ef094e10 00000016 f48c1e60 f48c1e70
 c1316bed f48c1e84 c1316bed 00000000 00000001 ef094e10 f48c1e84 f48c1ed0
 c1303cc6 c1303c7b f31f331a c1303cc6 f6e7d1c0 f3f8ea16 f3f8f380 f4d38008
Call Trace:
 [<c1316bed>] l2cap_disconn_cfm+0x3f/0x5b
 [<c1316bed>] ? l2cap_disconn_cfm+0x3f/0x5b
 [<c1303cc6>] hci_event_packet+0x645/0x2117
 [<c1303c7b>] ? hci_event_packet+0x5fa/0x2117
 [<c1303cc6>] ? hci_event_packet+0x645/0x2117
 [<c12681bd>] ? __kfree_skb+0x65/0x68
 [<c12681eb>] ? kfree_skb+0x2b/0x2e
 [<c130d3fb>] ? hci_send_to_sock+0x18d/0x199
 [<c12fa327>] hci_rx_work+0xf9/0x295
 [<c12fa327>] ? hci_rx_work+0xf9/0x295
 [<c1036d25>] process_one_work+0x128/0x1df
 [<c1346a39>] ? _raw_spin_unlock_irq+0x8/0x12
 [<c1036d25>] ? process_one_work+0x128/0x1df
 [<c103713a>] worker_thread+0x127/0x1c4
 [<c1037013>] ? rescuer_thread+0x216/0x216
 [<c103aec6>] kthread+0x88/0x8d
 [<c1040000>] ? task_rq_lock+0x37/0x6e
 [<c13474b7>] ret_from_kernel_thread+0x1b/0x28
 [<c103ae3e>] ? __kthread_parkme+0x50/0x50
Code: 05 b8 f4 ff ff ff 8d 65 f4 5b 5e 5f 5d 8d 67 f8 5f c3 57 8d 7c 24 08 83 e4 f8 ff 77 fc 55 89 e5 57 56f
EIP: [<c131e9c7>] bt_6lowpan_del_conn+0x19/0x12a SS:ESP 0068:f48c1e34
CR2: 0000000000000000

Signed-off-by: Johan Hedberg <[email protected]>
Signed-off-by: Marcel Holtmann <[email protected]>
tom3q pushed a commit that referenced this pull request Jan 11, 2014
Upon unload of the brcmfmac driver it gave a kernel warning because
cfg80211 still believed to be connected to an AP. The brcmfmac had
already transitioned to disconnected state during unload. This patch
adds informing cfg80211 about this transition. This will get rid of
warning from cfg80211 seen upon module unload:

 ------------[ cut here ]------------
 WARNING: CPU: 3 PID: 24303 at net/wireless/core.c:952
	cfg80211_netdev_notifier_call+0x193/0x640 [cfg80211]()
 Modules linked in: brcmfmac(O-) brcmutil(O) cfg80211(O) ... [last unloaded: bcma]
 CPU: 3 PID: 24303 Comm: rmmod Tainted: G        W  O 3.13.0-rc4-wl-testing-x64-00002-gb472b6d-dirty #1
 Hardware name: Dell Inc. Latitude E6410/07XJP9, BIOS A07 02/15/2011
  00000000000003b8 ffff8800b211faf8 ffffffff815a7fcd 0000000000000007
  0000000000000000 ffff8800b211fb38 ffffffff8104819c ffff880000000000
  ffff8800c889d008 ffff8800b2000220 ffff8800c889a000 ffff8800c889d018
 Call Trace:
  [<ffffffff815a7fcd>] dump_stack+0x46/0x58
  [<ffffffff8104819c>] warn_slowpath_common+0x8c/0xc0
  [<ffffffff810481ea>] warn_slowpath_null+0x1a/0x20
  [<ffffffffa173fd83>] cfg80211_netdev_notifier_call+0x193/0x640 [cfg80211]
  [<ffffffff81521ca8>] ? arp_ifdown+0x18/0x20
  [<ffffffff8152d75a>] ? fib_disable_ip+0x3a/0x50
  [<ffffffff815b143d>] notifier_call_chain+0x4d/0x70
  [<ffffffff8106d6e6>] raw_notifier_call_chain+0x16/0x20
  [<ffffffff814b9ae0>] call_netdevice_notifiers_info+0x40/0x70
  [<ffffffff814b9b26>] call_netdevice_notifiers+0x16/0x20
  [<ffffffff814bb59d>] rollback_registered_many+0x17d/0x280
  [<ffffffff814bb74d>] rollback_registered+0x2d/0x40
  [<ffffffff814bb7c8>] unregister_netdevice_queue+0x68/0xd0
  [<ffffffff814bb9c0>] unregister_netdev+0x20/0x30
  [<ffffffffa180069e>] brcmf_del_if+0xce/0x180 [brcmfmac]
  [<ffffffffa1800b3c>] brcmf_detach+0x6c/0xe0 [brcmfmac]

Reviewed-by: Hante Meuleman <[email protected]>
Reviewed-by: Pieter-Paul Giesberts <[email protected]>
Signed-off-by: Arend van Spriel <[email protected]>
Signed-off-by: John W. Linville <[email protected]>
tom3q pushed a commit that referenced this pull request Jan 11, 2014
…rt_entries()

[   89.237347] BUG: unable to handle kernel paging request at ffff880096326000
[   89.237369] IP: [<ffffffff81347227>] gen6_ppgtt_insert_entries+0x117/0x170
[   89.237382] PGD 2272067 PUD 25df0e067 PMD 25de5c067 PTE 8000000096326060
[   89.237394] Oops: 0000 [#1] SMP DEBUG_PAGEALLOC
[   89.237404] CPU: 1 PID: 1981 Comm: gem_concurrent_ Not tainted 3.13.0-rc4+ torvalds#639
[   89.237411] Hardware name: Intel Corporation 2012 Client Platform/Emerald Lake 2, BIOS ACRVMBY1.86C.0078.P00.1201161002 01/16/2012
[   89.237420] task: ffff88024c038030 ti: ffff88024b130000 task.ti: ffff88024b130000
[   89.237425] RIP: 0010:[<ffffffff81347227>]  [<ffffffff81347227>] gen6_ppgtt_insert_entries+0x117/0x170
[   89.237435] RSP: 0018:ffff88024b131ae0  EFLAGS: 00010286
[   89.237440] RAX: ffff880096325000 RBX: 0000000000000400 RCX: 0000000000001000
[   89.237445] RDX: 0000000000000200 RSI: 0000000000000001 RDI: 0000000000000010
[   89.237451] RBP: ffff88024b131b30 R08: ffff88024cc3aef0 R09: 0000000000000000
[   89.237456] R10: 0000000000000000 R11: 0000000000000000 R12: ffff88024cc3ae00
[   89.237462] R13: ffff88024a578000 R14: 0000000000000001 R15: ffff88024a578ffc
[   89.237469] FS:  00007ff5475d8900(0000) GS:ffff88025d020000(0000) knlGS:0000000000000000
[   89.237475] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   89.237480] CR2: ffff880096326000 CR3: 000000024d531000 CR4: 00000000001407e0
[   89.237485] Stack:
[   89.237488]  ffff880000000000 0000020000000000 ffff88024b23f2c0 0000000100000000
[   89.237499]  0000000000000001 000000000007ffff ffff8801e7bf5ac0 ffff8801e7bf5ac0
[   89.237510]  ffff88024cc3ae00 ffff880248a2ee40 ffff88024b131b58 ffffffff813455ed
[   89.237521] Call Trace:
[   89.237528]  [<ffffffff813455ed>] ppgtt_bind_vma+0x3d/0x60
[   89.237534]  [<ffffffff8133d8dc>] i915_gem_object_pin+0x55c/0x6a0
[   89.237541]  [<ffffffff8134275b>] i915_gem_execbuffer_reserve_vma.isra.14+0x5b/0x110
[   89.237548]  [<ffffffff81342a88>] i915_gem_execbuffer_reserve+0x278/0x2c0
[   89.237555]  [<ffffffff81343d29>] i915_gem_do_execbuffer.isra.22+0x699/0x1250
[   89.237562]  [<ffffffff81344d91>] ? i915_gem_execbuffer2+0x51/0x290
[   89.237569]  [<ffffffff81344de6>] i915_gem_execbuffer2+0xa6/0x290
[   89.237575]  [<ffffffff813014f2>] drm_ioctl+0x4d2/0x610
[   89.237582]  [<ffffffff81080bf1>] ? cpuacct_account_field+0xa1/0xc0
[   89.237588]  [<ffffffff81080b55>] ? cpuacct_account_field+0x5/0xc0
[   89.237597]  [<ffffffff811371c0>] do_vfs_ioctl+0x300/0x520
[   89.237603]  [<ffffffff810757a1>] ? vtime_account_user+0x91/0xa0
[   89.237610]  [<ffffffff810e40eb>] ?  context_tracking_user_exit+0x9b/0xe0
[   89.237617]  [<ffffffff81083d7d>] ? trace_hardirqs_on+0xd/0x10
[   89.237623]  [<ffffffff81137425>] SyS_ioctl+0x45/0x80
[   89.237630]  [<ffffffff815afffa>] tracesys+0xd4/0xd9
[   89.237634] Code: 5b 41 5c 41 5d 41 5e 41 5f 5d c3 66 0f 1f 84 00 00 00 00 00 83 45 bc 01 49 8b 84 24 78 01 00 00 65 ff 0c 25 e0 b8 00 00 8b 55 bc <4c> 8b 2c d0 65 ff 04 25 e0 b8 00 00 49 8b 45 00 48 c1 e8 2d 48
[   89.237741] RIP  [<ffffffff81347227>] gen6_ppgtt_insert_entries+0x117/0x170
[   89.237749]  RSP <ffff88024b131ae0>
[   89.237753] CR2: ffff880096326000
[   89.237758] ---[ end trace 27416ba8b18d496c ]---

This bug dates back to the original introduction of the
gen6_ppgtt_insert_entries()

Signed-off-by: Chris Wilson <[email protected]>
Cc: Daniel Vetter <[email protected]>
Cc: Ben Widawsky <[email protected]>
Reviewed-by: Ben Widawsky <[email protected]>
[danvet: Dropped cc: stable since without full ppgtt there's no way
we'll access the last page directory with this function since that
range is occupied (only in the allocator) with the ppgtt pdes. Without
aliasing we can start to use that range and blow up.]
Signed-off-by: Daniel Vetter <[email protected]>
tom3q pushed a commit that referenced this pull request Jan 11, 2014
In function free_dmar_iommu(), it sets IRQ handler data to NULL
before calling free_irq(), which will cause invalid memory access
because free_irq() will access IRQ handler data when calling
function dmar_msi_mask(). So only set IRQ handler data to NULL
after calling free_irq().

Sample stack dump:
[   13.094010] BUG: unable to handle kernel NULL pointer dereference at 0000000000000048
[   13.103215] IP: [<ffffffff810a97cd>] __lock_acquire+0x4d/0x12a0
[   13.110104] PGD 0
[   13.112614] Oops: 0000 [#1] SMP
[   13.116585] Modules linked in:
[   13.120260] CPU: 60 PID: 1 Comm: swapper/0 Tainted: G        W    3.13.0-rc1-gerry+ torvalds#9
[   13.129367] Hardware name: Intel Corporation LH Pass ........../SVRBD-ROW_T, BIOS SE5C600.86B.99.99.x059.091020121352 09/10/2012
[   13.142555] task: ffff88042dd38010 ti: ffff88042dd32000 task.ti: ffff88042dd32000
[   13.151179] RIP: 0010:[<ffffffff810a97cd>]  [<ffffffff810a97cd>] __lock_acquire+0x4d/0x12a0
[   13.160867] RSP: 0000:ffff88042dd33b78  EFLAGS: 00010046
[   13.166969] RAX: 0000000000000046 RBX: 0000000000000002 RCX: 0000000000000000
[   13.175122] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000048
[   13.183274] RBP: ffff88042dd33bd8 R08: 0000000000000002 R09: 0000000000000001
[   13.191417] R10: 0000000000000000 R11: 0000000000000001 R12: ffff88042dd38010
[   13.199571] R13: 0000000000000000 R14: 0000000000000048 R15: 0000000000000000
[   13.207725] FS:  0000000000000000(0000) GS:ffff88103f200000(0000) knlGS:0000000000000000
[   13.217014] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   13.223596] CR2: 0000000000000048 CR3: 0000000001a0b000 CR4: 00000000000407e0
[   13.231747] Stack:
[   13.234160]  0000000000000004 0000000000000046 ffff88042dd33b98 ffffffff810a567d
[   13.243059]  ffff88042dd33c08 ffffffff810bb14c ffffffff828995a0 0000000000000046
[   13.251969]  0000000000000000 0000000000000000 0000000000000002 0000000000000000
[   13.260862] Call Trace:
[   13.263775]  [<ffffffff810a567d>] ? trace_hardirqs_off+0xd/0x10
[   13.270571]  [<ffffffff810bb14c>] ? vprintk_emit+0x23c/0x570
[   13.277058]  [<ffffffff810ab1e3>] lock_acquire+0x93/0x120
[   13.283269]  [<ffffffff814623f7>] ? dmar_msi_mask+0x47/0x70
[   13.289677]  [<ffffffff8156b449>] _raw_spin_lock_irqsave+0x49/0x90
[   13.296748]  [<ffffffff814623f7>] ? dmar_msi_mask+0x47/0x70
[   13.303153]  [<ffffffff814623f7>] dmar_msi_mask+0x47/0x70
[   13.309354]  [<ffffffff810c0d93>] irq_shutdown+0x53/0x60
[   13.315467]  [<ffffffff810bdd9d>] __free_irq+0x26d/0x280
[   13.321580]  [<ffffffff810be920>] free_irq+0xf0/0x180
[   13.327395]  [<ffffffff81466591>] free_dmar_iommu+0x271/0x2b0
[   13.333996]  [<ffffffff810a947d>] ? trace_hardirqs_on+0xd/0x10
[   13.340696]  [<ffffffff81461a17>] free_iommu+0x17/0x50
[   13.346597]  [<ffffffff81dc75a5>] init_dmars+0x691/0x77a
[   13.352711]  [<ffffffff81dc7afd>] intel_iommu_init+0x351/0x438
[   13.359400]  [<ffffffff81d8a711>] ? iommu_setup+0x27d/0x27d
[   13.365806]  [<ffffffff81d8a739>] pci_iommu_init+0x28/0x52
[   13.372114]  [<ffffffff81000342>] do_one_initcall+0x122/0x180
[   13.378707]  [<ffffffff81077738>] ? parse_args+0x1e8/0x320
[   13.385016]  [<ffffffff81d850e8>] kernel_init_freeable+0x1e1/0x26c
[   13.392100]  [<ffffffff81d84833>] ? do_early_param+0x88/0x88
[   13.398596]  [<ffffffff8154f8b0>] ? rest_init+0xd0/0xd0
[   13.404614]  [<ffffffff8154f8be>] kernel_init+0xe/0x130
[   13.410626]  [<ffffffff81574d6c>] ret_from_fork+0x7c/0xb0
[   13.416829]  [<ffffffff8154f8b0>] ? rest_init+0xd0/0xd0
[   13.422842] Code: ec 99 00 85 c0 8b 05 53 05 a5 00 41 0f 45 d8 85 c0 0f 84 ff 00 00 00 8b 05 99 f9 7e 01 49 89 fe 41 89 f7 85 c0 0f 84 03 01 00 00 <49> 8b 06 be 01 00 00 00 48 3d c0 0e 01 82 0f 44 de 41 83 ff 01
[   13.450191] RIP  [<ffffffff810a97cd>] __lock_acquire+0x4d/0x12a0
[   13.458598]  RSP <ffff88042dd33b78>
[   13.462671] CR2: 0000000000000048
[   13.466551] ---[ end trace c5bd26a37c81d760 ]---

Reviewed-by: Yijing Wang <[email protected]>
Signed-off-by: Jiang Liu <[email protected]>
Signed-off-by: Joerg Roedel <[email protected]>
tom3q pushed a commit that referenced this pull request Jan 11, 2014
…ices

Data structure drhd->iommu is shared between DMA remapping driver and
interrupt remapping driver, so DMA remapping driver shouldn't release
drhd->iommu when it failed to initialize IOMMU devices. Otherwise it
may cause invalid memory access to the interrupt remapping driver.

Sample stack dump:
[   13.315090] BUG: unable to handle kernel paging request at ffffc9000605a088
[   13.323221] IP: [<ffffffff81461bac>] qi_submit_sync+0x15c/0x400
[   13.330107] PGD 82f81e067 PUD c2f81e067 PMD 82e846067 PTE 0
[   13.336818] Oops: 0002 [#1] SMP
[   13.340757] Modules linked in:
[   13.344422] CPU: 0 PID: 4 Comm: kworker/0:0 Not tainted 3.13.0-rc1-gerry+ torvalds#7
[   13.352474] Hardware name: Intel Corporation LH Pass ........../SVRBD-ROW_T,                                               BIOS SE5C600.86B.99.99.x059.091020121352 09/10/2012
[   13.365659] Workqueue: events work_for_cpu_fn
[   13.370774] task: ffff88042ddf00d0 ti: ffff88042ddee000 task.ti: ffff88042dde                                              e000
[   13.379389] RIP: 0010:[<ffffffff81461bac>]  [<ffffffff81461bac>] qi_submit_sy                                              nc+0x15c/0x400
[   13.389055] RSP: 0000:ffff88042ddef940  EFLAGS: 00010002
[   13.395151] RAX: 00000000000005e0 RBX: 0000000000000082 RCX: 0000000200000025
[   13.403308] RDX: ffffc9000605a000 RSI: 0000000000000010 RDI: ffff88042ddb8610
[   13.411446] RBP: ffff88042ddef9a0 R08: 00000000000005d0 R09: 0000000000000001
[   13.419599] R10: 0000000000000000 R11: 000000000000005d R12: 000000000000005c
[   13.427742] R13: ffff88102d84d300 R14: 0000000000000174 R15: ffff88042ddb4800
[   13.435877] FS:  0000000000000000(0000) GS:ffff88043de00000(0000) knlGS:00000                                              00000000000
[   13.445168] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   13.451749] CR2: ffffc9000605a088 CR3: 0000000001a0b000 CR4: 00000000000407f0
[   13.459895] Stack:
[   13.462297]  ffff88042ddb85d0 000000000000005d ffff88042ddef9b0 0000000000000                                              5d0
[   13.471147]  00000000000005c0 ffff88042ddb8000 000000000000005c 0000000000000                                              015
[   13.480001]  ffff88042ddb4800 0000000000000282 ffff88042ddefa40 ffff88042ddef                                              ac0
[   13.488855] Call Trace:
[   13.491771]  [<ffffffff8146848d>] modify_irte+0x9d/0xd0
[   13.497778]  [<ffffffff8146886d>] intel_setup_ioapic_entry+0x10d/0x290
[   13.505250]  [<ffffffff810a92a6>] ? trace_hardirqs_on_caller+0x16/0x1e0
[   13.512824]  [<ffffffff810346b0>] ? default_init_apic_ldr+0x60/0x60
[   13.519998]  [<ffffffff81468be0>] setup_ioapic_remapped_entry+0x20/0x30
[   13.527566]  [<ffffffff8103683a>] io_apic_setup_irq_pin+0x12a/0x2c0
[   13.534742]  [<ffffffff8136673b>] ? acpi_pci_irq_find_prt_entry+0x2b9/0x2d8
[   13.544102]  [<ffffffff81037fd5>] io_apic_setup_irq_pin_once+0x85/0xa0
[   13.551568]  [<ffffffff8103816f>] ? mp_find_ioapic_pin+0x8f/0xf0
[   13.558434]  [<ffffffff81038044>] io_apic_set_pci_routing+0x34/0x70
[   13.565621]  [<ffffffff8102f4cf>] mp_register_gsi+0xaf/0x1c0
[   13.572111]  [<ffffffff8102f5ee>] acpi_register_gsi_ioapic+0xe/0x10
[   13.579286]  [<ffffffff8102f33f>] acpi_register_gsi+0xf/0x20
[   13.585779]  [<ffffffff81366b86>] acpi_pci_irq_enable+0x171/0x1e3
[   13.592764]  [<ffffffff8146d771>] pcibios_enable_device+0x31/0x40
[   13.599744]  [<ffffffff81320e9b>] do_pci_enable_device+0x3b/0x60
[   13.606633]  [<ffffffff81322248>] pci_enable_device_flags+0xc8/0x120
[   13.613887]  [<ffffffff813222f3>] pci_enable_device+0x13/0x20
[   13.620484]  [<ffffffff8132fa7e>] pcie_port_device_register+0x1e/0x510
[   13.627947]  [<ffffffff810a92a6>] ? trace_hardirqs_on_caller+0x16/0x1e0
[   13.635510]  [<ffffffff810a947d>] ? trace_hardirqs_on+0xd/0x10
[   13.642189]  [<ffffffff813302b8>] pcie_portdrv_probe+0x58/0xc0
[   13.648877]  [<ffffffff81323ba5>] local_pci_probe+0x45/0xa0
[   13.655266]  [<ffffffff8106bc44>] work_for_cpu_fn+0x14/0x20
[   13.661656]  [<ffffffff8106fa79>] process_one_work+0x369/0x710
[   13.668334]  [<ffffffff8106fa02>] ? process_one_work+0x2f2/0x710
[   13.675215]  [<ffffffff81071d56>] ? worker_thread+0x46/0x690
[   13.681714]  [<ffffffff81072194>] worker_thread+0x484/0x690
[   13.688109]  [<ffffffff81071d10>] ? cancel_delayed_work_sync+0x20/0x20
[   13.695576]  [<ffffffff81079c60>] kthread+0xf0/0x110
[   13.701300]  [<ffffffff8108e7bf>] ? local_clock+0x3f/0x50
[   13.707492]  [<ffffffff81079b70>] ? kthread_create_on_node+0x250/0x250
[   13.714959]  [<ffffffff81574d2c>] ret_from_fork+0x7c/0xb0
[   13.721152]  [<ffffffff81079b70>] ? kthread_create_on_node+0x250/0x250

Signed-off-by: Jiang Liu <[email protected]>
Signed-off-by: Joerg Roedel <[email protected]>
tom3q pushed a commit that referenced this pull request Jan 11, 2014
When we pull a received packet from a link's 'deferred packets' queue
for processing, its 'next' pointer is not cleared, and still refers to
the next packet in that queue, if any. This is incorrect, but caused
no harm before commit 40ba3cd ("tipc:
message reassembly using fragment chain") was introduced. After that
commit, it may sometimes lead to the following oops:

general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC
Modules linked in: tipc
CPU: 4 PID: 0 Comm: swapper/4 Tainted: G        W 3.13.0-rc2+ torvalds#6
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007
task: ffff880017af4880 ti: ffff880017aee000 task.ti: ffff880017aee000
RIP: 0010:[<ffffffff81710694>]  [<ffffffff81710694>] skb_try_coalesce+0x44/0x3d0
RSP: 0018:ffff880016603a78  EFLAGS: 00010212
RAX: 6b6b6b6bd6d6d6d6 RBX: ffff880013106ac0 RCX: ffff880016603ad0
RDX: ffff880016603ad7 RSI: ffff88001223ed00 RDI: ffff880013106ac0
RBP: ffff880016603ab8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff88001223ed00
R13: ffff880016603ad0 R14: 000000000000058c R15: ffff880012297650
FS:  0000000000000000(0000) GS:ffff880016600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 000000000805b000 CR3: 0000000011f5d000 CR4: 00000000000006e0
Stack:
 ffff880016603a88 ffffffff810a38ed ffff880016603aa8 ffff88001223ed00
 0000000000000001 ffff880012297648 ffff880016603b68 ffff880012297650
 ffff880016603b08 ffffffffa0006c51 ffff880016603b08 00ffffffa00005fc
Call Trace:
 <IRQ>
 [<ffffffff810a38ed>] ? trace_hardirqs_on+0xd/0x10
 [<ffffffffa0006c51>] tipc_link_recv_fragment+0xd1/0x1b0 [tipc]
 [<ffffffffa0007214>] tipc_recv_msg+0x4e4/0x920 [tipc]
 [<ffffffffa00016f0>] ? tipc_l2_rcv_msg+0x40/0x250 [tipc]
 [<ffffffffa000177c>] tipc_l2_rcv_msg+0xcc/0x250 [tipc]
 [<ffffffffa00016f0>] ? tipc_l2_rcv_msg+0x40/0x250 [tipc]
 [<ffffffff8171e65b>] __netif_receive_skb_core+0x80b/0xd00
 [<ffffffff8171df94>] ? __netif_receive_skb_core+0x144/0xd00
 [<ffffffff8171eb76>] __netif_receive_skb+0x26/0x70
 [<ffffffff8171ed6d>] netif_receive_skb+0x2d/0x200
 [<ffffffff8171fe70>] napi_gro_receive+0xb0/0x130
 [<ffffffff815647c2>] e1000_clean_rx_irq+0x2c2/0x530
 [<ffffffff81565986>] e1000_clean+0x266/0x9c0
 [<ffffffff81985f7b>] ? notifier_call_chain+0x2b/0x160
 [<ffffffff8171f971>] net_rx_action+0x141/0x310
 [<ffffffff81051c1b>] __do_softirq+0xeb/0x480
 [<ffffffff819817bb>] ? _raw_spin_unlock+0x2b/0x40
 [<ffffffff810b8c42>] ? handle_fasteoi_irq+0x72/0x100
 [<ffffffff81052346>] irq_exit+0x96/0xc0
 [<ffffffff8198cbc3>] do_IRQ+0x63/0xe0
 [<ffffffff81981def>] common_interrupt+0x6f/0x6f
 <EOI>

This happens when the last fragment of a message has passed through the
the receiving link's 'deferred packets' queue, and at least one other
packet was added to that queue while it was there. After the fragment
chain with the complete message has been successfully delivered to the
receiving socket, it is released. Since 'next' pointer of the last
fragment in the released chain now is non-NULL, we get the crash shown
above.

We fix this by clearing the 'next' pointer of all received packets,
including those being pulled from the 'deferred' queue, before they
undergo any further processing.

Fixes: 40ba3cd ("tipc: message reassembly using fragment chain")
Signed-off-by: Erik Hugne <[email protected]>
Reported-by: Ying Xue <[email protected]>
Reviewed-by: Paul Gortmaker <[email protected]>
Signed-off-by: Jon Maloy <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
tom3q pushed a commit that referenced this pull request Jan 11, 2014
Jon Maloy says:

====================
tipc: link setup and failover improvements

This series consists of four unrelated commits with different purposes.

- Commit #1 is purely cosmetic and pedagogic, hopefully making the
  failover/tunneling logics slightly easier to understand.
- Commit #2 fixes a bug that has always been in the code, but was not
  discovered until very recently.
- Commit #3 fixes a non-fatal race issue in the neighbour discovery
  code.
- Commit #4 removes an unnecessary indirection step during link
  startup.
====================

Signed-off-by: David S. Miller <[email protected]>
tom3q pushed a commit that referenced this pull request Jan 11, 2014
This fixes the following warning:

  BUG: sleeping function called from invalid context at mm/slub.c:940
  in_atomic(): 1, irqs_disabled(): 1, pid: 17, name: khubd
  CPU: 0 PID: 17 Comm: khubd Not tainted 3.12.0-00004-g938dd60-dirty #1

   __might_sleep+0xbe/0xc0
   kmem_cache_alloc_trace+0x36/0x170
   c67x00_urb_enqueue+0x5c/0x254
   usb_hcd_submit_urb+0x66e/0x724
   usb_submit_urb+0x2ac/0x308
   usb_start_wait_urb+0x2c/0xb8
   usb_control_msg+0x8c/0xa8
   hub_port_init+0x191/0x718
   hub_thread+0x804/0xe14
   kthread+0x72/0x78
   ret_from_kernel_thread+0x8/0xc

Signed-off-by: Max Filippov <[email protected]>
Acked-by: Peter Korsgaard <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
tom3q pushed a commit that referenced this pull request Jan 11, 2014
Avoid that bus_unregister() triggers a use-after-free with
CONFIG_DEBUG_KOBJECT_RELEASE=y. This patch avoids that the
following sequence triggers a kernel crash with memory poisoning
enabled:
* bus_register()
* driver_register()
* driver_unregister()
* bus_unregister()

The above sequence causes the bus private data to be freed from
inside the bus_unregister() call although it is not guaranteed in
that function that the reference count on the bus private data has
dropped to zero. As an example, with CONFIG_DEBUG_KOBJECT_RELEASE=y
the ${bus}/drivers kobject is still holding a reference on
bus->p->subsys.kobj via its parent pointer at the time the bus
private data is freed. Fix this by deferring freeing the bus private
data until the last kobject_put() call on bus->p->subsys.kobj.

The kernel oops triggered by the above sequence and with memory
poisoning enabled and that is fixed by this patch is as follows:

general protection fault: 0000 [#1] PREEMPT SMP
CPU: 3 PID: 2711 Comm: kworker/3:32 Tainted: G        W  O 3.13.0-rc4-debug+ #1
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
Workqueue: events kobject_delayed_cleanup
task: ffff880037f866d0 ti: ffff88003b638000 task.ti: ffff88003b638000
Call Trace:
 [<ffffffff81263105>] ? kobject_get_path+0x25/0x100
 [<ffffffff81264354>] kobject_uevent_env+0x134/0x600
 [<ffffffff8126482b>] kobject_uevent+0xb/0x10
 [<ffffffff81262fa2>] kobject_delayed_cleanup+0xc2/0x1b0
 [<ffffffff8106c047>] process_one_work+0x217/0x700
 [<ffffffff8106bfdb>] ? process_one_work+0x1ab/0x700
 [<ffffffff8106c64b>] worker_thread+0x11b/0x3a0
 [<ffffffff8106c530>] ? process_one_work+0x700/0x700
 [<ffffffff81074b70>] kthread+0xf0/0x110
 [<ffffffff81074a80>] ? insert_kthread_work+0x80/0x80
 [<ffffffff815673bc>] ret_from_fork+0x7c/0xb0
 [<ffffffff81074a80>] ? insert_kthread_work+0x80/0x80
Code: 89 f8 48 89 e5 f6 82 c0 27 63 81 20 74 15 0f 1f 44 00 00 48 83 c0 01 0f b6 10 f6 82 c0 27 63 81 20 75 f0 5d c3 66 0f 1f 44 00 00 <80> 3f 00 55 48 89 e5 74 15 48 89 f8 0f 1f 40 00 48 83 c0 01 80
RIP  [<ffffffff81267ed0>] strlen+0x0/0x30
 RSP <ffff88003b639c70>
---[ end trace 210f883ef80376aa ]---

Signed-off-by: Bart Van Assche <[email protected]>
Acked-by: Ming Lei <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
tom3q pushed a commit that referenced this pull request Jan 11, 2014
Commit 14bd8c0 ("MIPS: Loongson: Get rid of Loongson 2 #ifdefery
all over arch/mips") failed to add Loongson2 specific blast_icache32
functions.  Fix that.

The patch fixes the following crash seen with 3.13-rc1:

[    3.652000] Reserved instruction in kernel code[#1]:
[...]
[    3.652000] Call Trace:
[    3.652000] [<ffffffff802223c8>] blast_icache32_page+0x8/0xb0
[    3.652000] [<ffffffff80222c34>] r4k_flush_cache_page+0x19c/0x200
[    3.652000] [<ffffffff802d17e4>] do_wp_page.isra.97+0x47c/0xe08
[    3.652000] [<ffffffff802d51b0>] handle_mm_fault+0x938/0x1118
[    3.652000] [<ffffffff8021bd40>] __do_page_fault+0x140/0x540
[    3.652000] [<ffffffff80206be4>] resume_userspace_check+0x0/0x10
[    3.652000]
[    3.652000] Code: 00200825  64834000  00200825 <bc900000> bc900020  bc900040  bc900060  bc900080  bc9000a0
[    3.656000] ---[ end trace cd8a48f722f5c5f7 ]---

Signed-off-by: Aaro Koskinen <[email protected]>
Reviewed-by: Aurelien Jarno <[email protected]>
Acked-by: John Crispin <[email protected]>
Cc: Ralf Baechle <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
tom3q pushed a commit that referenced this pull request Jan 11, 2014
objrmap doesn't work for nonlinear VMAs because the assumption that
offset-into-file correlates with offset-into-virtual-addresses does not
hold.  Hence what try_to_unmap_cluster does is a mini "virtual scan" of
each nonlinear VMA which maps the file to which the target page belongs.
If vma locked, mlock the pages in the cluster, rather than unmapping them.
However, not all pages are guarantee page locked instead of the check
page, resulting in the below BUG_ON().

It's safe to mlock_vma_page() without PageLocked, so fix this issue by
removing that BUG_ON().

[  253.869145] kernel BUG at mm/mlock.c:82!
[  253.869549] invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
[  253.870098] Dumping ftrace buffer:
[  253.870098]    (ftrace buffer empty)
[  253.870098] Modules linked in:
[  253.870098] CPU: 10 PID: 9162 Comm: trinity-child75 Tainted: G        W 3.13.0-rc4-next-20131216-sasha-00011-g5f105ec-dirty #4137
[  253.873310] task: ffff8800c98cb000 ti: ffff8804d34e8000 task.ti: ffff8804d34e8000
[  253.873310] RIP: 0010:[<ffffffff81281f28>]  [<ffffffff81281f28>] mlock_vma_page+0x18/0xc0
[  253.873310] RSP: 0000:ffff8804d34e99e8  EFLAGS: 00010246
[  253.873310] RAX: 006fffff8038002c RBX: ffffea00474944c0 RCX: ffff880807636000
[  253.873310] RDX: ffffea0000000000 RSI: 00007f17a9bca000 RDI: ffffea00474944c0
[  253.873310] RBP: ffff8804d34e99f8 R08: ffff880807020000 R09: 0000000000000000
[  253.873310] R10: 0000000000000001 R11: 0000000000002000 R12: 00007f17a9bca000
[  253.873310] R13: ffffea00474944c0 R14: 00007f17a9be0000 R15: ffff880807020000
[  253.873310] FS:  00007f17aa31a700(0000) GS:ffff8801c9c00000(0000) knlGS:0000000000000000
[  253.873310] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[  253.873310] CR2: 00007f17a94fa000 CR3: 00000004d3b02000 CR4: 00000000000006e0
[  253.873310] DR0: 00007f17a74ca000 DR1: 0000000000000000 DR2: 0000000000000000
[  253.873310] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
[  253.873310] Stack:
[  253.873310]  0000000b3de28067 ffff880b3de28e50 ffff8804d34e9aa8 ffffffff8128bc31
[  253.873310]  0000000000000301 ffffea0011850220 ffff8809a4039000 ffffea0011850238
[  253.873310]  ffff8804d34e9aa8 ffff880807636060 0000000000000001 ffff880807636348
[  253.873310] Call Trace:
[  253.873310]  [<ffffffff8128bc31>] try_to_unmap_cluster+0x1c1/0x340
[  253.873310]  [<ffffffff8128c60a>] try_to_unmap_file+0x20a/0x2e0
[  253.873310]  [<ffffffff8128c7b3>] try_to_unmap+0x73/0x90
[  253.873310]  [<ffffffff812b526d>] __unmap_and_move+0x18d/0x250
[  253.873310]  [<ffffffff812b53e9>] unmap_and_move+0xb9/0x180
[  253.873310]  [<ffffffff812b559b>] migrate_pages+0xeb/0x2f0
[  253.873310]  [<ffffffff812a0660>] ? queue_pages_pte_range+0x1a0/0x1a0
[  253.873310]  [<ffffffff812a193c>] migrate_to_node+0x9c/0xc0
[  253.873310]  [<ffffffff812a30b8>] do_migrate_pages+0x1b8/0x240
[  253.873310]  [<ffffffff812a3456>] SYSC_migrate_pages+0x316/0x380
[  253.873310]  [<ffffffff812a31ec>] ? SYSC_migrate_pages+0xac/0x380
[  253.873310]  [<ffffffff811763c6>] ? vtime_account_user+0x96/0xb0
[  253.873310]  [<ffffffff812a34ce>] SyS_migrate_pages+0xe/0x10
[  253.873310]  [<ffffffff843c4990>] tracesys+0xdd/0xe2
[  253.873310] Code: 0f 1f 00 65 48 ff 04 25 10 25 1d 00 48 83 c4 08
5b c9 c3 55 48 89 e5 53 48 83 ec 08 66 66 66 66 90 48 8b 07 48 89 fb
a8 01 75 10 <0f> 0b 66 0f 1f 44 00 00 eb fe 66 0f 1f 44 00 00 f0 0f ba
2f 15
[  253.873310] RIP  [<ffffffff81281f28>] mlock_vma_page+0x18/0xc0
[  253.873310]  RSP <ffff8804d34e99e8>
[  253.904194] ---[ end trace be59c4a7f8edab3f ]---

Signed-off-by: Bob Liu <[email protected]>
Reported-by: Sasha Levin <[email protected]>
Cc: Wanpeng Li <[email protected]>
Cc: Michel Lespinasse <[email protected]>
Cc: Rik van Riel <[email protected]>
Cc: KOSAKI Motohiro <[email protected]>
Cc: David Rientjes <[email protected]>
Cc: Mel Gorman <[email protected]>
Cc: Minchan Kim <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: Hugh Dickins <[email protected]>
Cc: Johannes Weiner <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
tom3q pushed a commit that referenced this pull request Jan 11, 2014
…r thp split

After thp split in hwpoison_user_mappings(), we hold page lock on the raw
error page only between try_to_unmap, hence we are in danger of race condition.

I found in the RHEL7 MCE-relay testing that we have "bad page" error
when a memory error happens on a thp tail page used by qemu-kvm:

  Triggering MCE exception on CPU 10
  mce: [Hardware Error]: Machine check events logged
  MCE exception done on CPU 10
  MCE 0x38c535: Killing qemu-kvm:8418 due to hardware memory corruption
  MCE 0x38c535: dirty LRU page recovery: Recovered
  qemu-kvm[8418]: segfault at 20 ip 00007ffb0f0f229a sp 00007fffd6bc5240 error 4 in qemu-kvm[7ffb0ef14000+420000]
  BUG: Bad page state in process qemu-kvm  pfn:38c400
  page:ffffea000e310000 count:0 mapcount:0 mapping:          (null) index:0x7ffae3c00
  page flags: 0x2fffff0008001d(locked|referenced|uptodate|dirty|swapbacked)
  Modules linked in: hwpoison_inject mce_inject vhost_net macvtap macvlan ...
  CPU: 0 PID: 8418 Comm: qemu-kvm Tainted: G   M        --------------   3.10.0-54.0.1.el7.mce_test_fixed.x86_64 #1
  Hardware name: NEC NEC Express5800/R120b-1 [N8100-1719F]/MS-91E7-001, BIOS 4.6.3C19 02/10/2011
   000fffff00000000 ffff8802fc9239a0 ffffffff815b4cc0 ffff8802fc9239b8
   ffffffff815b072e 0000000000000000 ffff8802fc9239f8 ffffffff8113b918
   ffffea000e310000 ffffea000e310000 002fffff0008001d 0000000000000000
  Call Trace:
   [<ffffffff815b4cc0>] dump_stack+0x19/0x1b
   [<ffffffff815b072e>] bad_page.part.59+0xcf/0xe8
   [<ffffffff8113b918>] free_pages_prepare+0x148/0x160
   [<ffffffff8113c231>] free_hot_cold_page+0x31/0x140
   [<ffffffff8113c386>] free_hot_cold_page_list+0x46/0xa0
   [<ffffffff81141361>] release_pages+0x1c1/0x200
   [<ffffffff8116e47d>] free_pages_and_swap_cache+0xad/0xd0
   [<ffffffff8115850c>] tlb_flush_mmu.part.46+0x4c/0x90
   [<ffffffff81159045>] tlb_finish_mmu+0x55/0x60
   [<ffffffff81163e6b>] exit_mmap+0xcb/0x170
   [<ffffffff81055f87>] mmput+0x67/0xf0
   [<ffffffffa05c7451>] vhost_dev_cleanup+0x231/0x260 [vhost_net]
   [<ffffffffa05ca0df>] vhost_net_release+0x3f/0x90 [vhost_net]
   [<ffffffff8119f649>] __fput+0xe9/0x270
   [<ffffffff8119f8fe>] ____fput+0xe/0x10
   [<ffffffff8107b754>] task_work_run+0xc4/0xe0
   [<ffffffff8105e88b>] do_exit+0x2bb/0xa40
   [<ffffffff8106b0cc>] ? __dequeue_signal+0x13c/0x220
   [<ffffffff8105f08f>] do_group_exit+0x3f/0xa0
   [<ffffffff8106dcc0>] get_signal_to_deliver+0x1d0/0x6e0
   [<ffffffff81012408>] do_signal+0x48/0x5e0
   [<ffffffff8106ee48>] ? do_sigaction+0x88/0x1f0
   [<ffffffff81012a11>] do_notify_resume+0x71/0xc0
   [<ffffffff815bc53c>] retint_signal+0x48/0x8c

The reason of this bug is that a page fault happens before unlocking
the head page at the end of memory_failure().
This strange page fault is trying to access to address 0x20 and I'm not
sure why qemu-kvm does this, but anyway as a result the SIGSEGV makes
qemu-kvm exit and on the way we catch the bad page bug/warning because
we try to free a locked page (which was the former head page.)

To fix this, this patch suggests to shift page lock from head page to
tail page just after thp split. SIGSEGV still happens, but it affects
only error affected VMs, not a whole system.

Signed-off-by: Naoya Horiguchi <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Wanpeng Li <[email protected]>
Cc: <[email protected]>        [3.9+] # a3e0f9e "mm/memory-failure.c: transfer page count from head page to tail page after split thp"
Signed-off-by: Andrew Morton <[email protected]>
tom3q pushed a commit that referenced this pull request Jan 11, 2014
…heck

If the type we receive is greater than ST_MAX_CHANNELS we can't rely on
type as vector index since we would be accessing unknown memory when we use the type
as index.

 Unable to handle kernel NULL pointer dereference at virtual address 0000001b
 pgd = c0004000
 [0000001b] *pgd=00000000
 Internal error: Oops: 17 [#1] PREEMPT SMP ARM
 Modules linked in: btwilink wl12xx wlcore mac80211 cfg80211 rfcomm bnep bluo
 CPU: 0    Tainted: G        W     (3.4.0+ torvalds#15)
 PC is at st_int_recv+0x278/0x344
 LR is at get_parent_ip+0x14/0x30
 pc : [<c03b01a8>]    lr : [<c007273c>]    psr: 200f0193
 sp : dc631ed0  ip : e3e21c24  fp : dc631f04
 r10: 00000000  r9 : 600f0113  r8 : 0000003f
 r7 : e3e21b14  r6 : 00000067  r5 : e2e49c1c  r4 : e3e21a80
 r3 : 00000001  r2 : 00000001  r1 : 00000001  r0 : 600f0113
 Flags: nzCv  IRQs off  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
 Control: 10c5387d  Table: 9c50004a  DAC: 00000015

Signed-off-by: Gustavo Padovan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
tom3q pushed a commit that referenced this pull request Mar 4, 2014
As part of normal operaions, the hrtimer subsystem frequently calls
into the timekeeping code, creating a locking order of
  hrtimer locks -> timekeeping locks

clock_was_set_delayed() was suppoed to allow us to avoid deadlocks
between the timekeeping the hrtimer subsystem, so that we could
notify the hrtimer subsytem the time had changed while holding
the timekeeping locks. This was done by scheduling delayed work
that would run later once we were out of the timekeeing code.

But unfortunately the lock chains are complex enoguh that in
scheduling delayed work, we end up eventually trying to grab
an hrtimer lock.

Sasha Levin noticed this in testing when the new seqlock lockdep
enablement triggered the following (somewhat abrieviated) message:

[  251.100221] ======================================================
[  251.100221] [ INFO: possible circular locking dependency detected ]
[  251.100221] 3.13.0-rc2-next-20131206-sasha-00005-g8be2375-dirty #4053 Not tainted
[  251.101967] -------------------------------------------------------
[  251.101967] kworker/10:1/4506 is trying to acquire lock:
[  251.101967]  (timekeeper_seq){----..}, at: [<ffffffff81160e96>] retrigger_next_event+0x56/0x70
[  251.101967]
[  251.101967] but task is already holding lock:
[  251.101967]  (hrtimer_bases.lock#11){-.-...}, at: [<ffffffff81160e7c>] retrigger_next_event+0x3c/0x70
[  251.101967]
[  251.101967] which lock already depends on the new lock.
[  251.101967]
[  251.101967]
[  251.101967] the existing dependency chain (in reverse order) is:
[  251.101967]
-> #5 (hrtimer_bases.lock#11){-.-...}:
[snipped]
-> #4 (&rt_b->rt_runtime_lock){-.-...}:
[snipped]
-> #3 (&rq->lock){-.-.-.}:
[snipped]
-> #2 (&p->pi_lock){-.-.-.}:
[snipped]
-> #1 (&(&pool->lock)->rlock){-.-...}:
[  251.101967]        [<ffffffff81194803>] validate_chain+0x6c3/0x7b0
[  251.101967]        [<ffffffff81194d9d>] __lock_acquire+0x4ad/0x580
[  251.101967]        [<ffffffff81194ff2>] lock_acquire+0x182/0x1d0
[  251.101967]        [<ffffffff84398500>] _raw_spin_lock+0x40/0x80
[  251.101967]        [<ffffffff81153e69>] __queue_work+0x1a9/0x3f0
[  251.101967]        [<ffffffff81154168>] queue_work_on+0x98/0x120
[  251.101967]        [<ffffffff81161351>] clock_was_set_delayed+0x21/0x30
[  251.101967]        [<ffffffff811c4bd1>] do_adjtimex+0x111/0x160
[  251.101967]        [<ffffffff811e2711>] compat_sys_adjtimex+0x41/0x70
[  251.101967]        [<ffffffff843a4b49>] ia32_sysret+0x0/0x5
[  251.101967]
-> #0 (timekeeper_seq){----..}:
[snipped]
[  251.101967] other info that might help us debug this:
[  251.101967]
[  251.101967] Chain exists of:
  timekeeper_seq --> &rt_b->rt_runtime_lock --> hrtimer_bases.lock#11

[  251.101967]  Possible unsafe locking scenario:
[  251.101967]
[  251.101967]        CPU0                    CPU1
[  251.101967]        ----                    ----
[  251.101967]   lock(hrtimer_bases.lock#11);
[  251.101967]                                lock(&rt_b->rt_runtime_lock);
[  251.101967]                                lock(hrtimer_bases.lock#11);
[  251.101967]   lock(timekeeper_seq);
[  251.101967]
[  251.101967]  *** DEADLOCK ***
[  251.101967]
[  251.101967] 3 locks held by kworker/10:1/4506:
[  251.101967]  #0:  (events){.+.+.+}, at: [<ffffffff81154960>] process_one_work+0x200/0x530
[  251.101967]  #1:  (hrtimer_work){+.+...}, at: [<ffffffff81154960>] process_one_work+0x200/0x530
[  251.101967]  #2:  (hrtimer_bases.lock#11){-.-...}, at: [<ffffffff81160e7c>] retrigger_next_event+0x3c/0x70
[  251.101967]
[  251.101967] stack backtrace:
[  251.101967] CPU: 10 PID: 4506 Comm: kworker/10:1 Not tainted 3.13.0-rc2-next-20131206-sasha-00005-g8be2375-dirty #4053
[  251.101967] Workqueue: events clock_was_set_work

So the best solution is to avoid calling clock_was_set_delayed() while
holding the timekeeping lock, and instead using a flag variable to
decide if we should call clock_was_set() once we've released the locks.

This works for the case here, where the do_adjtimex() was the deadlock
trigger point. Unfortuantely, in update_wall_time() we still hold
the jiffies lock, which would deadlock with the ipi triggered by
clock_was_set(), preventing us from calling it even after we drop the
timekeeping lock. So instead call clock_was_set_delayed() at that point.

Cc: Thomas Gleixner <[email protected]>
Cc: Prarit Bhargava <[email protected]>
Cc: Richard Cochran <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Sasha Levin <[email protected]>
Cc: stable <[email protected]> #3.10+
Reported-by: Sasha Levin <[email protected]>
Tested-by: Sasha Levin <[email protected]>
Signed-off-by: John Stultz <[email protected]>
tom3q pushed a commit that referenced this pull request Mar 4, 2014
For devices with a separated audio-only interface (em2860), call
em28xx_init_extension() only once.

That fixes a bug with Kworld 305U (eb1a:e305):

    [  658.730715] em2860 #0: V4L2 video device registered as video1
    [  658.730728] em2860 #0: V4L2 VBI device registered as vbi0
    [  658.736907] em2860 #0: Remote control support is not available for this card.
    [  658.736965] em2860 #1: Remote control support is not available for this card.
    [  658.737230] ------------[ cut here ]------------
    [  658.737246] WARNING: CPU: 2 PID: 60 at lib/list_debug.c:36 __list_add+0x8a/0xc0()
    [  658.737256] list_add double add: new=ffff8800a9a40410, prev=ffff8800a9a40410, next=ffffffffa08720d0.
    [  658.737266] Modules linked in: tuner_xc2028 netconsole rc_hauppauge em28xx_rc rc_core tuner_simple tuner_types tda9887 tda8290 tuner tvp5150 msp3400 em28xx_v4l em28xx tveeprom
 v4l2_common fuse ccm nf_conntrack_netbios_ns nf_conntrack_broadcast ipt_MASQUERADE ip6t_REJECT xt_conntrack ebtable_nat ebtable_broute bridge stp llc ebtable_filter ebtables ip6tabl
e_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_mangle ip6table_security ip6table_raw ip6table_filter ip6_tables iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4
nf_nat nf_conntrack iptable_mangle iptable_security bnep iptable_raw vfat fat arc4 iwldvm mac80211 x86_pkg_temp_thermal coretemp kvm_intel nfsd iwlwifi snd_hda_codec_hdmi kvm snd_hda
_codec_realtek snd_hda_intel snd_hda_codec auth_rpcgss nfs_acl cfg80211 lockd snd_hwdep snd_seq btusb sunrpc crc32_pclmul bluetooth crc32c_intel snd_seq_device snd_pcm uvcvideo r8169
 ghash_clmulni_intel videobuf2_vmalloc videobuf2_memops videobuf2_core snd_page_alloc snd_timer snd videodev mei_me iTCO_wdt mii shpchp joydev mei media iTCO_vendor_support lpc_ich m
icrocode soundcore rfkill serio_raw i2c_i801 mfd_core nouveau i915 ttm i2c_algo_bit drm_kms_helper drm i2c_core mxm_wmi wmi video
    [  658.738601] CPU: 2 PID: 60 Comm: kworker/2:1 Not tainted 3.13.0-rc1+ torvalds#18
    [  658.738611] Hardware name: SAMSUNG ELECTRONICS CO., LTD. 550P5C/550P7C/SAMSUNG_NP1234567890, BIOS P04ABI.013.130220.dg 02/20/2013
    [  658.738624] Workqueue: events request_module_async [em28xx]
    [  658.738646]  0000000000000009 ffff8802209dfc68 ffffffff816a3c96 ffff8802209dfcb0
    [  658.738700]  ffff8802209dfca0 ffffffff8106aaad ffff8800a9a40410 ffffffffa08720d0
    [  658.738754]  ffff8800a9a40410 0000000000000000 0000000000000080 ffff8802209dfd00
    [  658.738814] Call Trace:
    [  658.738836]  [<ffffffff816a3c96>] dump_stack+0x45/0x56
    [  658.738851]  [<ffffffff8106aaad>] warn_slowpath_common+0x7d/0xa0
    [  658.738864]  [<ffffffff8106ab1c>] warn_slowpath_fmt+0x4c/0x50
    [  658.738880]  [<ffffffffa0868a7d>] ? em28xx_init_extension+0x1d/0x80 [em28xx]
    [  658.738898]  [<ffffffff81343b8a>] __list_add+0x8a/0xc0
    [  658.738911]  [<ffffffffa0868a98>] em28xx_init_extension+0x38/0x80 [em28xx]
    [  658.738927]  [<ffffffffa086a059>] request_module_async+0x19/0x110 [em28xx]
    [  658.738942]  [<ffffffff810873b5>] process_one_work+0x1f5/0x510
    [  658.738954]  [<ffffffff81087353>] ? process_one_work+0x193/0x510
    [  658.738967]  [<ffffffff810880bb>] worker_thread+0x11b/0x3a0
    [  658.738979]  [<ffffffff81087fa0>] ? manage_workers.isra.24+0x2b0/0x2b0
    [  658.738992]  [<ffffffff8108ea2f>] kthread+0xff/0x120
    [  658.739005]  [<ffffffff8108e930>] ? kthread_create_on_node+0x250/0x250
    [  658.739017]  [<ffffffff816b517c>] ret_from_fork+0x7c/0xb0
    [  658.739029]  [<ffffffff8108e930>] ? kthread_create_on_node+0x250/0x250
    [  658.739040] ---[ end trace c1acd24b354108de ]---
    [  658.739051] em2860 #1: Remote control support is not available for this card.
    [  658.742407] em28xx-audio.c: probing for em28xx Audio Vendor Class
    [  658.742429] em28xx-audio.c: Copyright (C) 2006 Markus Rechberger
    [  658.742440] em28xx-audio.c: Copyright (C) 2007-2011 Mauro Carvalho Chehab
    [  658.744798] em28xx-audio.c: probing for em28xx Audio Vendor Class
    [  658.744823] em28xx-audio.c: Copyright (C) 2006 Markus Rechberger
    [  658.744836] em28xx-audio.c: Copyright (C) 2007-2011 Mauro Carvalho Chehab
    [  658.746849] em28xx-audio.c: probing for em28xx Audio Vendor Class
    [  658.746863] em28xx-audio.c: Copyright (C) 2006 Markus Rechberger
    [  658.746874] em28xx-audio.c: Copyright (C) 2007-2011 Mauro Carvalho Chehab
    ...

Signed-off-by: Mauro Carvalho Chehab <[email protected]>
tom3q pushed a commit that referenced this pull request Mar 4, 2014
In function free_dmar_iommu(), it sets IRQ handler data to NULL
before calling free_irq(), which will cause invalid memory access
because free_irq() will access IRQ handler data when calling
function dmar_msi_mask(). So only set IRQ handler data to NULL
after calling free_irq().

Sample stack dump:
[   13.094010] BUG: unable to handle kernel NULL pointer dereference at 0000000000000048
[   13.103215] IP: [<ffffffff810a97cd>] __lock_acquire+0x4d/0x12a0
[   13.110104] PGD 0
[   13.112614] Oops: 0000 [#1] SMP
[   13.116585] Modules linked in:
[   13.120260] CPU: 60 PID: 1 Comm: swapper/0 Tainted: G        W    3.13.0-rc1-gerry+ torvalds#9
[   13.129367] Hardware name: Intel Corporation LH Pass ........../SVRBD-ROW_T, BIOS SE5C600.86B.99.99.x059.091020121352 09/10/2012
[   13.142555] task: ffff88042dd38010 ti: ffff88042dd32000 task.ti: ffff88042dd32000
[   13.151179] RIP: 0010:[<ffffffff810a97cd>]  [<ffffffff810a97cd>] __lock_acquire+0x4d/0x12a0
[   13.160867] RSP: 0000:ffff88042dd33b78  EFLAGS: 00010046
[   13.166969] RAX: 0000000000000046 RBX: 0000000000000002 RCX: 0000000000000000
[   13.175122] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000048
[   13.183274] RBP: ffff88042dd33bd8 R08: 0000000000000002 R09: 0000000000000001
[   13.191417] R10: 0000000000000000 R11: 0000000000000001 R12: ffff88042dd38010
[   13.199571] R13: 0000000000000000 R14: 0000000000000048 R15: 0000000000000000
[   13.207725] FS:  0000000000000000(0000) GS:ffff88103f200000(0000) knlGS:0000000000000000
[   13.217014] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   13.223596] CR2: 0000000000000048 CR3: 0000000001a0b000 CR4: 00000000000407e0
[   13.231747] Stack:
[   13.234160]  0000000000000004 0000000000000046 ffff88042dd33b98 ffffffff810a567d
[   13.243059]  ffff88042dd33c08 ffffffff810bb14c ffffffff828995a0 0000000000000046
[   13.251969]  0000000000000000 0000000000000000 0000000000000002 0000000000000000
[   13.260862] Call Trace:
[   13.263775]  [<ffffffff810a567d>] ? trace_hardirqs_off+0xd/0x10
[   13.270571]  [<ffffffff810bb14c>] ? vprintk_emit+0x23c/0x570
[   13.277058]  [<ffffffff810ab1e3>] lock_acquire+0x93/0x120
[   13.283269]  [<ffffffff814623f7>] ? dmar_msi_mask+0x47/0x70
[   13.289677]  [<ffffffff8156b449>] _raw_spin_lock_irqsave+0x49/0x90
[   13.296748]  [<ffffffff814623f7>] ? dmar_msi_mask+0x47/0x70
[   13.303153]  [<ffffffff814623f7>] dmar_msi_mask+0x47/0x70
[   13.309354]  [<ffffffff810c0d93>] irq_shutdown+0x53/0x60
[   13.315467]  [<ffffffff810bdd9d>] __free_irq+0x26d/0x280
[   13.321580]  [<ffffffff810be920>] free_irq+0xf0/0x180
[   13.327395]  [<ffffffff81466591>] free_dmar_iommu+0x271/0x2b0
[   13.333996]  [<ffffffff810a947d>] ? trace_hardirqs_on+0xd/0x10
[   13.340696]  [<ffffffff81461a17>] free_iommu+0x17/0x50
[   13.346597]  [<ffffffff81dc75a5>] init_dmars+0x691/0x77a
[   13.352711]  [<ffffffff81dc7afd>] intel_iommu_init+0x351/0x438
[   13.359400]  [<ffffffff81d8a711>] ? iommu_setup+0x27d/0x27d
[   13.365806]  [<ffffffff81d8a739>] pci_iommu_init+0x28/0x52
[   13.372114]  [<ffffffff81000342>] do_one_initcall+0x122/0x180
[   13.378707]  [<ffffffff81077738>] ? parse_args+0x1e8/0x320
[   13.385016]  [<ffffffff81d850e8>] kernel_init_freeable+0x1e1/0x26c
[   13.392100]  [<ffffffff81d84833>] ? do_early_param+0x88/0x88
[   13.398596]  [<ffffffff8154f8b0>] ? rest_init+0xd0/0xd0
[   13.404614]  [<ffffffff8154f8be>] kernel_init+0xe/0x130
[   13.410626]  [<ffffffff81574d6c>] ret_from_fork+0x7c/0xb0
[   13.416829]  [<ffffffff8154f8b0>] ? rest_init+0xd0/0xd0
[   13.422842] Code: ec 99 00 85 c0 8b 05 53 05 a5 00 41 0f 45 d8 85 c0 0f 84 ff 00 00 00 8b 05 99 f9 7e 01 49 89 fe 41 89 f7 85 c0 0f 84 03 01 00 00 <49> 8b 06 be 01 00 00 00 48 3d c0 0e 01 82 0f 44 de 41 83 ff 01
[   13.450191] RIP  [<ffffffff810a97cd>] __lock_acquire+0x4d/0x12a0
[   13.458598]  RSP <ffff88042dd33b78>
[   13.462671] CR2: 0000000000000048
[   13.466551] ---[ end trace c5bd26a37c81d760 ]---

Reviewed-by: Yijing Wang <[email protected]>
Signed-off-by: Jiang Liu <[email protected]>
Signed-off-by: Joerg Roedel <[email protected]>
tom3q pushed a commit that referenced this pull request Mar 4, 2014
…ices

Data structure drhd->iommu is shared between DMA remapping driver and
interrupt remapping driver, so DMA remapping driver shouldn't release
drhd->iommu when it failed to initialize IOMMU devices. Otherwise it
may cause invalid memory access to the interrupt remapping driver.

Sample stack dump:
[   13.315090] BUG: unable to handle kernel paging request at ffffc9000605a088
[   13.323221] IP: [<ffffffff81461bac>] qi_submit_sync+0x15c/0x400
[   13.330107] PGD 82f81e067 PUD c2f81e067 PMD 82e846067 PTE 0
[   13.336818] Oops: 0002 [#1] SMP
[   13.340757] Modules linked in:
[   13.344422] CPU: 0 PID: 4 Comm: kworker/0:0 Not tainted 3.13.0-rc1-gerry+ torvalds#7
[   13.352474] Hardware name: Intel Corporation LH Pass ........../SVRBD-ROW_T,                                               BIOS SE5C600.86B.99.99.x059.091020121352 09/10/2012
[   13.365659] Workqueue: events work_for_cpu_fn
[   13.370774] task: ffff88042ddf00d0 ti: ffff88042ddee000 task.ti: ffff88042dde                                              e000
[   13.379389] RIP: 0010:[<ffffffff81461bac>]  [<ffffffff81461bac>] qi_submit_sy                                              nc+0x15c/0x400
[   13.389055] RSP: 0000:ffff88042ddef940  EFLAGS: 00010002
[   13.395151] RAX: 00000000000005e0 RBX: 0000000000000082 RCX: 0000000200000025
[   13.403308] RDX: ffffc9000605a000 RSI: 0000000000000010 RDI: ffff88042ddb8610
[   13.411446] RBP: ffff88042ddef9a0 R08: 00000000000005d0 R09: 0000000000000001
[   13.419599] R10: 0000000000000000 R11: 000000000000005d R12: 000000000000005c
[   13.427742] R13: ffff88102d84d300 R14: 0000000000000174 R15: ffff88042ddb4800
[   13.435877] FS:  0000000000000000(0000) GS:ffff88043de00000(0000) knlGS:00000                                              00000000000
[   13.445168] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   13.451749] CR2: ffffc9000605a088 CR3: 0000000001a0b000 CR4: 00000000000407f0
[   13.459895] Stack:
[   13.462297]  ffff88042ddb85d0 000000000000005d ffff88042ddef9b0 0000000000000                                              5d0
[   13.471147]  00000000000005c0 ffff88042ddb8000 000000000000005c 0000000000000                                              015
[   13.480001]  ffff88042ddb4800 0000000000000282 ffff88042ddefa40 ffff88042ddef                                              ac0
[   13.488855] Call Trace:
[   13.491771]  [<ffffffff8146848d>] modify_irte+0x9d/0xd0
[   13.497778]  [<ffffffff8146886d>] intel_setup_ioapic_entry+0x10d/0x290
[   13.505250]  [<ffffffff810a92a6>] ? trace_hardirqs_on_caller+0x16/0x1e0
[   13.512824]  [<ffffffff810346b0>] ? default_init_apic_ldr+0x60/0x60
[   13.519998]  [<ffffffff81468be0>] setup_ioapic_remapped_entry+0x20/0x30
[   13.527566]  [<ffffffff8103683a>] io_apic_setup_irq_pin+0x12a/0x2c0
[   13.534742]  [<ffffffff8136673b>] ? acpi_pci_irq_find_prt_entry+0x2b9/0x2d8
[   13.544102]  [<ffffffff81037fd5>] io_apic_setup_irq_pin_once+0x85/0xa0
[   13.551568]  [<ffffffff8103816f>] ? mp_find_ioapic_pin+0x8f/0xf0
[   13.558434]  [<ffffffff81038044>] io_apic_set_pci_routing+0x34/0x70
[   13.565621]  [<ffffffff8102f4cf>] mp_register_gsi+0xaf/0x1c0
[   13.572111]  [<ffffffff8102f5ee>] acpi_register_gsi_ioapic+0xe/0x10
[   13.579286]  [<ffffffff8102f33f>] acpi_register_gsi+0xf/0x20
[   13.585779]  [<ffffffff81366b86>] acpi_pci_irq_enable+0x171/0x1e3
[   13.592764]  [<ffffffff8146d771>] pcibios_enable_device+0x31/0x40
[   13.599744]  [<ffffffff81320e9b>] do_pci_enable_device+0x3b/0x60
[   13.606633]  [<ffffffff81322248>] pci_enable_device_flags+0xc8/0x120
[   13.613887]  [<ffffffff813222f3>] pci_enable_device+0x13/0x20
[   13.620484]  [<ffffffff8132fa7e>] pcie_port_device_register+0x1e/0x510
[   13.627947]  [<ffffffff810a92a6>] ? trace_hardirqs_on_caller+0x16/0x1e0
[   13.635510]  [<ffffffff810a947d>] ? trace_hardirqs_on+0xd/0x10
[   13.642189]  [<ffffffff813302b8>] pcie_portdrv_probe+0x58/0xc0
[   13.648877]  [<ffffffff81323ba5>] local_pci_probe+0x45/0xa0
[   13.655266]  [<ffffffff8106bc44>] work_for_cpu_fn+0x14/0x20
[   13.661656]  [<ffffffff8106fa79>] process_one_work+0x369/0x710
[   13.668334]  [<ffffffff8106fa02>] ? process_one_work+0x2f2/0x710
[   13.675215]  [<ffffffff81071d56>] ? worker_thread+0x46/0x690
[   13.681714]  [<ffffffff81072194>] worker_thread+0x484/0x690
[   13.688109]  [<ffffffff81071d10>] ? cancel_delayed_work_sync+0x20/0x20
[   13.695576]  [<ffffffff81079c60>] kthread+0xf0/0x110
[   13.701300]  [<ffffffff8108e7bf>] ? local_clock+0x3f/0x50
[   13.707492]  [<ffffffff81079b70>] ? kthread_create_on_node+0x250/0x250
[   13.714959]  [<ffffffff81574d2c>] ret_from_fork+0x7c/0xb0
[   13.721152]  [<ffffffff81079b70>] ? kthread_create_on_node+0x250/0x250

Signed-off-by: Jiang Liu <[email protected]>
Signed-off-by: Joerg Roedel <[email protected]>
tom3q pushed a commit that referenced this pull request Mar 4, 2014
…ssion()

While running stress tests on adding and deleting ftrace instances I hit
this bug:

  BUG: unable to handle kernel NULL pointer dereference at 0000000000000020
  IP: selinux_inode_permission+0x85/0x160
  PGD 63681067 PUD 7ddbe067 PMD 0
  Oops: 0000 [#1] PREEMPT
  CPU: 0 PID: 5634 Comm: ftrace-test-mki Not tainted 3.13.0-rc4-test-00033-gd2a6dde-dirty torvalds#20
  Hardware name:                  /DG965MQ, BIOS MQ96510J.86A.0372.2006.0605.1717 06/05/2006
  task: ffff880078375800 ti: ffff88007ddb0000 task.ti: ffff88007ddb0000
  RIP: 0010:[<ffffffff812d8bc5>]  [<ffffffff812d8bc5>] selinux_inode_permission+0x85/0x160
  RSP: 0018:ffff88007ddb1c48  EFLAGS: 00010246
  RAX: 0000000000000000 RBX: 0000000000800000 RCX: ffff88006dd43840
  RDX: 0000000000000001 RSI: 0000000000000081 RDI: ffff88006ee46000
  RBP: ffff88007ddb1c88 R08: 0000000000000000 R09: ffff88007ddb1c54
  R10: 6e6576652f6f6f66 R11: 0000000000000003 R12: 0000000000000000
  R13: 0000000000000081 R14: ffff88006ee46000 R15: 0000000000000000
  FS:  00007f217b5b6700(0000) GS:ffffffff81e21000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033^M
  CR2: 0000000000000020 CR3: 000000006a0fe000 CR4: 00000000000007f0
  Call Trace:
    security_inode_permission+0x1c/0x30
    __inode_permission+0x41/0xa0
    inode_permission+0x18/0x50
    link_path_walk+0x66/0x920
    path_openat+0xa6/0x6c0
    do_filp_open+0x43/0xa0
    do_sys_open+0x146/0x240
    SyS_open+0x1e/0x20
    system_call_fastpath+0x16/0x1b
  Code: 84 a1 00 00 00 81 e3 00 20 00 00 89 d8 83 c8 02 40 f6 c6 04 0f 45 d8 40 f6 c6 08 74 71 80 cf 02 49 8b 46 38 4c 8d 4d cc 45 31 c0 <0f> b7 50 20 8b 70 1c 48 8b 41 70 89 d9 8b 78 04 e8 36 cf ff ff
  RIP  selinux_inode_permission+0x85/0x160
  CR2: 0000000000000020

Investigating, I found that the inode->i_security was NULL, and the
dereference of it caused the oops.

in selinux_inode_permission():

	isec = inode->i_security;

	rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd);

Note, the crash came from stressing the deletion and reading of debugfs
files.  I was not able to recreate this via normal files.  But I'm not
sure they are safe.  It may just be that the race window is much harder
to hit.

What seems to have happened (and what I have traced), is the file is
being opened at the same time the file or directory is being deleted.
As the dentry and inode locks are not held during the path walk, nor is
the inodes ref counts being incremented, there is nothing saving these
structures from being discarded except for an rcu_read_lock().

The rcu_read_lock() protects against freeing of the inode, but it does
not protect freeing of the inode_security_struct.  Now if the freeing of
the i_security happens with a call_rcu(), and the i_security field of
the inode is not changed (it gets freed as the inode gets freed) then
there will be no issue here.  (Linus Torvalds suggested not setting the
field to NULL such that we do not need to check if it is NULL in the
permission check).

Note, this is a hack, but it fixes the problem at hand.  A real fix is
to restructure the destroy_inode() to call all the destructor handlers
from the RCU callback.  But that is a major job to do, and requires a
lot of work.  For now, we just band-aid this bug with this fix (it
works), and work on a more maintainable solution in the future.

Link: http://lkml.kernel.org/r/[email protected]
Link: http://lkml.kernel.org/r/[email protected]

Cc: [email protected]
Signed-off-by: Steven Rostedt <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
tom3q pushed a commit that referenced this pull request Mar 4, 2014
The below tells us the static_key conversion has a problem; since the
exact point of clearing that flag isn't too important, delay the flip
and use a workqueue to process it.

[ ] TSC synchronization [CPU#0 -> CPU#22]:
[ ] Measured 8 cycles TSC warp between CPUs, turning off TSC clock.
[ ]
[ ] ======================================================
[ ] [ INFO: possible circular locking dependency detected ]
[ ] 3.13.0-rc3-01745-g848b0d0322cb-dirty torvalds#637 Not tainted
[ ] -------------------------------------------------------
[ ] swapper/0/1 is trying to acquire lock:
[ ]  (jump_label_mutex){+.+...}, at: [<ffffffff8115a637>] jump_label_lock+0x17/0x20
[ ]
[ ] but task is already holding lock:
[ ]  (cpu_hotplug.lock){+.+.+.}, at: [<ffffffff8109408b>] cpu_hotplug_begin+0x2b/0x60
[ ]
[ ] which lock already depends on the new lock.
[ ]
[ ]
[ ] the existing dependency chain (in reverse order) is:
[ ]
[ ] -> #1 (cpu_hotplug.lock){+.+.+.}:
[ ]        [<ffffffff810def00>] lock_acquire+0x90/0x130
[ ]        [<ffffffff81661f83>] mutex_lock_nested+0x63/0x3e0
[ ]        [<ffffffff81093fdc>] get_online_cpus+0x3c/0x60
[ ]        [<ffffffff8104cc67>] arch_jump_label_transform+0x37/0x130
[ ]        [<ffffffff8115a3cf>] __jump_label_update+0x5f/0x80
[ ]        [<ffffffff8115a48d>] jump_label_update+0x9d/0xb0
[ ]        [<ffffffff8115aa6d>] static_key_slow_inc+0x9d/0xb0
[ ]        [<ffffffff810c0f65>] sched_feat_set+0xf5/0x100
[ ]        [<ffffffff810c5bdc>] set_numabalancing_state+0x2c/0x30
[ ]        [<ffffffff81d12f3d>] numa_policy_init+0x1af/0x1b7
[ ]        [<ffffffff81cebdf4>] start_kernel+0x35d/0x41f
[ ]        [<ffffffff81ceb5a5>] x86_64_start_reservations+0x2a/0x2c
[ ]        [<ffffffff81ceb6a2>] x86_64_start_kernel+0xfb/0xfe
[ ]
[ ] -> #0 (jump_label_mutex){+.+...}:
[ ]        [<ffffffff810de141>] __lock_acquire+0x1701/0x1eb0
[ ]        [<ffffffff810def00>] lock_acquire+0x90/0x130
[ ]        [<ffffffff81661f83>] mutex_lock_nested+0x63/0x3e0
[ ]        [<ffffffff8115a637>] jump_label_lock+0x17/0x20
[ ]        [<ffffffff8115aa3b>] static_key_slow_inc+0x6b/0xb0
[ ]        [<ffffffff810ca775>] clear_sched_clock_stable+0x15/0x20
[ ]        [<ffffffff810503b3>] mark_tsc_unstable+0x23/0x70
[ ]        [<ffffffff810772cb>] check_tsc_sync_source+0x14b/0x150
[ ]        [<ffffffff81076612>] native_cpu_up+0x3a2/0x890
[ ]        [<ffffffff810941cb>] _cpu_up+0xdb/0x160
[ ]        [<ffffffff810942c9>] cpu_up+0x79/0x90
[ ]        [<ffffffff81d0af6b>] smp_init+0x60/0x8c
[ ]        [<ffffffff81cebf42>] kernel_init_freeable+0x8c/0x197
[ ]        [<ffffffff8164e32e>] kernel_init+0xe/0x130
[ ]        [<ffffffff8166beec>] ret_from_fork+0x7c/0xb0
[ ]
[ ] other info that might help us debug this:
[ ]
[ ]  Possible unsafe locking scenario:
[ ]
[ ]        CPU0                    CPU1
[ ]        ----                    ----
[ ]   lock(cpu_hotplug.lock);
[ ]                                lock(jump_label_mutex);
[ ]                                lock(cpu_hotplug.lock);
[ ]   lock(jump_label_mutex);
[ ]
[ ]  *** DEADLOCK ***
[ ]
[ ] 2 locks held by swapper/0/1:
[ ]  #0:  (cpu_add_remove_lock){+.+.+.}, at: [<ffffffff81094037>] cpu_maps_update_begin+0x17/0x20
[ ]  #1:  (cpu_hotplug.lock){+.+.+.}, at: [<ffffffff8109408b>] cpu_hotplug_begin+0x2b/0x60
[ ]
[ ] stack backtrace:
[ ] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.13.0-rc3-01745-g848b0d0322cb-dirty torvalds#637
[ ] Hardware name: Supermicro X8DTN/X8DTN, BIOS 4.6.3 01/08/2010
[ ]  ffffffff82c9c270 ffff880236843bb8 ffffffff8165c5f5 ffffffff82c9c270
[ ]  ffff880236843bf8 ffffffff81658c02 ffff880236843c80 ffff8802368586a0
[ ]  ffff880236858678 0000000000000001 0000000000000002 ffff880236858000
[ ] Call Trace:
[ ]  [<ffffffff8165c5f5>] dump_stack+0x4e/0x7a
[ ]  [<ffffffff81658c02>] print_circular_bug+0x1f9/0x207
[ ]  [<ffffffff810de141>] __lock_acquire+0x1701/0x1eb0
[ ]  [<ffffffff816680ff>] ? __atomic_notifier_call_chain+0x8f/0xb0
[ ]  [<ffffffff810def00>] lock_acquire+0x90/0x130
[ ]  [<ffffffff8115a637>] ? jump_label_lock+0x17/0x20
[ ]  [<ffffffff8115a637>] ? jump_label_lock+0x17/0x20
[ ]  [<ffffffff81661f83>] mutex_lock_nested+0x63/0x3e0
[ ]  [<ffffffff8115a637>] ? jump_label_lock+0x17/0x20
[ ]  [<ffffffff8115a637>] jump_label_lock+0x17/0x20
[ ]  [<ffffffff8115aa3b>] static_key_slow_inc+0x6b/0xb0
[ ]  [<ffffffff810ca775>] clear_sched_clock_stable+0x15/0x20
[ ]  [<ffffffff810503b3>] mark_tsc_unstable+0x23/0x70
[ ]  [<ffffffff810772cb>] check_tsc_sync_source+0x14b/0x150
[ ]  [<ffffffff81076612>] native_cpu_up+0x3a2/0x890
[ ]  [<ffffffff810941cb>] _cpu_up+0xdb/0x160
[ ]  [<ffffffff810942c9>] cpu_up+0x79/0x90
[ ]  [<ffffffff81d0af6b>] smp_init+0x60/0x8c
[ ]  [<ffffffff81cebf42>] kernel_init_freeable+0x8c/0x197
[ ]  [<ffffffff8164e320>] ? rest_init+0xd0/0xd0
[ ]  [<ffffffff8164e32e>] kernel_init+0xe/0x130
[ ]  [<ffffffff8166beec>] ret_from_fork+0x7c/0xb0
[ ]  [<ffffffff8164e320>] ? rest_init+0xd0/0xd0
[ ] ------------[ cut here ]------------
[ ] WARNING: CPU: 0 PID: 1 at /usr/src/linux-2.6/kernel/smp.c:374 smp_call_function_many+0xad/0x300()
[ ] Modules linked in:
[ ] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.13.0-rc3-01745-g848b0d0322cb-dirty torvalds#637
[ ] Hardware name: Supermicro X8DTN/X8DTN, BIOS 4.6.3 01/08/2010
[ ]  0000000000000009 ffff880236843be0 ffffffff8165c5f5 0000000000000000
[ ]  ffff880236843c18 ffffffff81093d8c 0000000000000000 0000000000000000
[ ]  ffffffff81ccd1a0 ffffffff810ca951 0000000000000000 ffff880236843c28
[ ] Call Trace:
[ ]  [<ffffffff8165c5f5>] dump_stack+0x4e/0x7a
[ ]  [<ffffffff81093d8c>] warn_slowpath_common+0x8c/0xc0
[ ]  [<ffffffff810ca951>] ? sched_clock_tick+0x1/0xa0
[ ]  [<ffffffff81093dda>] warn_slowpath_null+0x1a/0x20
[ ]  [<ffffffff8110b72d>] smp_call_function_many+0xad/0x300
[ ]  [<ffffffff8104f200>] ? arch_unregister_cpu+0x30/0x30
[ ]  [<ffffffff8104f200>] ? arch_unregister_cpu+0x30/0x30
[ ]  [<ffffffff810ca951>] ? sched_clock_tick+0x1/0xa0
[ ]  [<ffffffff8110ba96>] smp_call_function+0x46/0x80
[ ]  [<ffffffff8104f200>] ? arch_unregister_cpu+0x30/0x30
[ ]  [<ffffffff8110bb3c>] on_each_cpu+0x3c/0xa0
[ ]  [<ffffffff810ca950>] ? sched_clock_idle_sleep_event+0x20/0x20
[ ]  [<ffffffff810ca951>] ? sched_clock_tick+0x1/0xa0
[ ]  [<ffffffff8104f964>] text_poke_bp+0x64/0xd0
[ ]  [<ffffffff810ca950>] ? sched_clock_idle_sleep_event+0x20/0x20
[ ]  [<ffffffff8104ccde>] arch_jump_label_transform+0xae/0x130
[ ]  [<ffffffff8115a3cf>] __jump_label_update+0x5f/0x80
[ ]  [<ffffffff8115a48d>] jump_label_update+0x9d/0xb0
[ ]  [<ffffffff8115aa6d>] static_key_slow_inc+0x9d/0xb0
[ ]  [<ffffffff810ca775>] clear_sched_clock_stable+0x15/0x20
[ ]  [<ffffffff810503b3>] mark_tsc_unstable+0x23/0x70
[ ]  [<ffffffff810772cb>] check_tsc_sync_source+0x14b/0x150
[ ]  [<ffffffff81076612>] native_cpu_up+0x3a2/0x890
[ ]  [<ffffffff810941cb>] _cpu_up+0xdb/0x160
[ ]  [<ffffffff810942c9>] cpu_up+0x79/0x90
[ ]  [<ffffffff81d0af6b>] smp_init+0x60/0x8c
[ ]  [<ffffffff81cebf42>] kernel_init_freeable+0x8c/0x197
[ ]  [<ffffffff8164e320>] ? rest_init+0xd0/0xd0
[ ]  [<ffffffff8164e32e>] kernel_init+0xe/0x130
[ ]  [<ffffffff8166beec>] ret_from_fork+0x7c/0xb0
[ ]  [<ffffffff8164e320>] ? rest_init+0xd0/0xd0
[ ] ---[ end trace 6ff1df5620c49d26 ]---
[ ] tsc: Marking TSC unstable due to check_tsc_sync_source failed

Signed-off-by: Peter Zijlstra <[email protected]>
Link: http://lkml.kernel.org/n/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
tom3q pushed a commit that referenced this pull request Mar 4, 2014
Sometimes we may meet the following lockdep issue.
The root cause is .set_clock callback is executed with spin_lock_irqsave
in sdhci_do_set_ios. However, the IMX set_clock callback will try to access
clk_get_rate which is using a mutex lock.

The fix avoids access mutex in .set_clock callback by initializing the
pltfm_host->clock at probe time and use it later instead of calling
clk_get_rate again in atomic context.

[ INFO: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected ]
3.13.0-rc1+ torvalds#285 Not tainted
------------------------------------------------------
kworker/u8:1/29 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire:
 (prepare_lock){+.+...}, at: [<80480b08>] clk_prepare_lock+0x44/0xe4

and this task is already holding:
 (&(&host->lock)->rlock#2){-.-...}, at: [<804611f4>] sdhci_do_set_ios+0x20/0x720
which would create a new lock dependency:
 (&(&host->lock)->rlock#2){-.-...} -> (prepare_lock){+.+...}

but this new dependency connects a HARDIRQ-irq-safe lock:
 (&(&host->lock)->rlock#2){-.-...}
... which became HARDIRQ-irq-safe at:
  [<8005f030>] mark_lock+0x140/0x6ac
  [<80060760>] __lock_acquire+0xb30/0x1cbc
  [<800620d0>] lock_acquire+0x70/0x84
  [<8061d2f0>] _raw_spin_lock+0x30/0x40
  [<80460668>] sdhci_irq+0x24/0xa68
  [<8006b1d4>] handle_irq_event_percpu+0x54/0x18c
  [<8006b350>] handle_irq_event+0x44/0x64
  [<8006e50c>] handle_fasteoi_irq+0xa0/0x170
  [<8006a8f0>] generic_handle_irq+0x30/0x44
  [<8000f238>] handle_IRQ+0x54/0xbc
  [<8000864c>] gic_handle_irq+0x30/0x64
  [<80013024>] __irq_svc+0x44/0x5c
  [<80614c58>] printk+0x38/0x40
  [<804622a8>] sdhci_add_host+0x844/0xbcc
  [<80464948>] sdhci_esdhc_imx_probe+0x378/0x67c
  [<8032ee88>] platform_drv_probe+0x20/0x50
  [<8032d48c>] driver_probe_device+0x118/0x234
  [<8032d690>] __driver_attach+0x9c/0xa0
  [<8032b89c>] bus_for_each_dev+0x68/0x9c
  [<8032cf44>] driver_attach+0x20/0x28
  [<8032cbc8>] bus_add_driver+0x148/0x1f4
  [<8032dce0>] driver_register+0x80/0x100
  [<8032ee54>] __platform_driver_register+0x50/0x64
  [<8084b094>] sdhci_esdhc_imx_driver_init+0x18/0x20
  [<80008980>] do_one_initcall+0x108/0x16c
  [<8081cca4>] kernel_init_freeable+0x10c/0x1d0
  [<80611c50>] kernel_init+0x10/0x120
  [<8000e9c8>] ret_from_fork+0x14/0x2c

to a HARDIRQ-irq-unsafe lock:
 (prepare_lock){+.+...}
... which became HARDIRQ-irq-unsafe at:
...  [<8005f030>] mark_lock+0x140/0x6ac
  [<8005f604>] mark_held_locks+0x68/0x12c
  [<8005f780>] trace_hardirqs_on_caller+0xb8/0x1d8
  [<8005f8b4>] trace_hardirqs_on+0x14/0x18
  [<8061a130>] mutex_trylock+0x180/0x20c
  [<80480ad8>] clk_prepare_lock+0x14/0xe4
  [<804816a4>] clk_notifier_register+0x28/0xf0
  [<80015120>] twd_clk_init+0x50/0x68
  [<80008980>] do_one_initcall+0x108/0x16c
  [<8081cca4>] kernel_init_freeable+0x10c/0x1d0
  [<80611c50>] kernel_init+0x10/0x120
  [<8000e9c8>] ret_from_fork+0x14/0x2c

other info that might help us debug this:

 Possible interrupt unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(prepare_lock);
                               local_irq_disable();
                               lock(&(&host->lock)->rlock#2);
                               lock(prepare_lock);
  <Interrupt>
    lock(&(&host->lock)->rlock#2);

 *** DEADLOCK ***

3 locks held by kworker/u8:1/29:
 #0:  (kmmcd){.+.+.+}, at: [<8003db18>] process_one_work+0x128/0x468
 #1:  ((&(&host->detect)->work)){+.+.+.}, at: [<8003db18>] process_one_work+0x128/0x468
 #2:  (&(&host->lock)->rlock#2){-.-...}, at: [<804611f4>] sdhci_do_set_ios+0x20/0x720

the dependencies between HARDIRQ-irq-safe lock and the holding lock:
-> (&(&host->lock)->rlock#2){-.-...} ops: 330 {
   IN-HARDIRQ-W at:
                    [<8005f030>] mark_lock+0x140/0x6ac
                    [<80060760>] __lock_acquire+0xb30/0x1cbc
                    [<800620d0>] lock_acquire+0x70/0x84
                    [<8061d2f0>] _raw_spin_lock+0x30/0x40
                    [<80460668>] sdhci_irq+0x24/0xa68
                    [<8006b1d4>] handle_irq_event_percpu+0x54/0x18c
                    [<8006b350>] handle_irq_event+0x44/0x64
                    [<8006e50c>] handle_fasteoi_irq+0xa0/0x170
                    [<8006a8f0>] generic_handle_irq+0x30/0x44
                    [<8000f238>] handle_IRQ+0x54/0xbc
                    [<8000864c>] gic_handle_irq+0x30/0x64
                    [<80013024>] __irq_svc+0x44/0x5c
                    [<80614c58>] printk+0x38/0x40
                    [<804622a8>] sdhci_add_host+0x844/0xbcc
                    [<80464948>] sdhci_esdhc_imx_probe+0x378/0x67c
                    [<8032ee88>] platform_drv_probe+0x20/0x50
                    [<8032d48c>] driver_probe_device+0x118/0x234
                    [<8032d690>] __driver_attach+0x9c/0xa0
                    [<8032b89c>] bus_for_each_dev+0x68/0x9c
                    [<8032cf44>] driver_attach+0x20/0x28
                    [<8032cbc8>] bus_add_driver+0x148/0x1f4
                    [<8032dce0>] driver_register+0x80/0x100
                    [<8032ee54>] __platform_driver_register+0x50/0x64
                    [<8084b094>] sdhci_esdhc_imx_driver_init+0x18/0x20
                    [<80008980>] do_one_initcall+0x108/0x16c
                    [<8081cca4>] kernel_init_freeable+0x10c/0x1d0
                    [<80611c50>] kernel_init+0x10/0x120
                    [<8000e9c8>] ret_from_fork+0x14/0x2c
   IN-SOFTIRQ-W at:
                    [<8005f030>] mark_lock+0x140/0x6ac
                    [<80060204>] __lock_acquire+0x5d4/0x1cbc
                    [<800620d0>] lock_acquire+0x70/0x84
                    [<8061d40c>] _raw_spin_lock_irqsave+0x40/0x54
                    [<8045e4a4>] sdhci_tasklet_finish+0x1c/0x120
                    [<8002b538>] tasklet_action+0xa0/0x15c
                    [<8002b778>] __do_softirq+0x118/0x290
                    [<8002bcf4>] irq_exit+0xb4/0x10c
                    [<8000f240>] handle_IRQ+0x5c/0xbc
                    [<8000864c>] gic_handle_irq+0x30/0x64
                    [<80013024>] __irq_svc+0x44/0x5c
                    [<80614c58>] printk+0x38/0x40
                    [<804622a8>] sdhci_add_host+0x844/0xbcc
                    [<80464948>] sdhci_esdhc_imx_probe+0x378/0x67c
                    [<8032ee88>] platform_drv_probe+0x20/0x50
                    [<8032d48c>] driver_probe_device+0x118/0x234
                    [<8032d690>] __driver_attach+0x9c/0xa0
                    [<8032b89c>] bus_for_each_dev+0x68/0x9c
                    [<8032cf44>] driver_attach+0x20/0x28
                    [<8032cbc8>] bus_add_driver+0x148/0x1f4
                    [<8032dce0>] driver_register+0x80/0x100
                    [<8032ee54>] __platform_driver_register+0x50/0x64
                    [<8084b094>] sdhci_esdhc_imx_driver_init+0x18/0x20
                    [<80008980>] do_one_initcall+0x108/0x16c
                    [<8081cca4>] kernel_init_freeable+0x10c/0x1d0
                    [<80611c50>] kernel_init+0x10/0x120
                    [<8000e9c8>] ret_from_fork+0x14/0x2c
   INITIAL USE at:
                   [<8005f030>] mark_lock+0x140/0x6ac
                   [<8005ff0c>] __lock_acquire+0x2dc/0x1cbc
                   [<800620d0>] lock_acquire+0x70/0x84
                   [<8061d40c>] _raw_spin_lock_irqsave+0x40/0x54
                   [<804611f4>] sdhci_do_set_ios+0x20/0x720
                   [<80461924>] sdhci_set_ios+0x30/0x3c
                   [<8044cea0>] mmc_power_up+0x6c/0xd0
                   [<8044dac4>] mmc_start_host+0x60/0x70
                   [<8044eb3c>] mmc_add_host+0x60/0x88
                   [<8046225c>] sdhci_add_host+0x7f8/0xbcc
                   [<80464948>] sdhci_esdhc_imx_probe+0x378/0x67c
                   [<8032ee88>] platform_drv_probe+0x20/0x50
                   [<8032d48c>] driver_probe_device+0x118/0x234
                   [<8032d690>] __driver_attach+0x9c/0xa0
                   [<8032b89c>] bus_for_each_dev+0x68/0x9c
                   [<8032cf44>] driver_attach+0x20/0x28
                   [<8032cbc8>] bus_add_driver+0x148/0x1f4
                   [<8032dce0>] driver_register+0x80/0x100
                   [<8032ee54>] __platform_driver_register+0x50/0x64
                   [<8084b094>] sdhci_esdhc_imx_driver_init+0x18/0x20
                   [<80008980>] do_one_initcall+0x108/0x16c
                   [<8081cca4>] kernel_init_freeable+0x10c/0x1d0
                   [<80611c50>] kernel_init+0x10/0x120
                   [<8000e9c8>] ret_from_fork+0x14/0x2c
 }
 ... key      at: [<80e040e8>] __key.26952+0x0/0x8
 ... acquired at:
   [<8005eb60>] check_usage+0x3d0/0x5c0
   [<8005edac>] check_irq_usage+0x5c/0xb8
   [<80060d38>] __lock_acquire+0x1108/0x1cbc
   [<800620d0>] lock_acquire+0x70/0x84
   [<8061a210>] mutex_lock_nested+0x54/0x3c0
   [<80480b08>] clk_prepare_lock+0x44/0xe4
   [<8048188c>] clk_get_rate+0x14/0x64
   [<8046374c>] esdhc_pltfm_set_clock+0x20/0x2a4
   [<8045d70c>] sdhci_set_clock+0x4c/0x498
   [<80461518>] sdhci_do_set_ios+0x344/0x720
   [<80461924>] sdhci_set_ios+0x30/0x3c
   [<8044c390>] __mmc_set_clock+0x44/0x60
   [<8044cd4c>] mmc_set_clock+0x10/0x14
   [<8044f8f4>] mmc_init_card+0x1b4/0x1520
   [<80450f00>] mmc_attach_mmc+0xb4/0x194
   [<8044da08>] mmc_rescan+0x294/0x2f0
   [<8003db94>] process_one_work+0x1a4/0x468
   [<8003e850>] worker_thread+0x118/0x3e0
   [<80044de0>] kthread+0xd4/0xf0
   [<8000e9c8>] ret_from_fork+0x14/0x2c

the dependencies between the lock to be acquired and HARDIRQ-irq-unsafe lock:
-> (prepare_lock){+.+...} ops: 395 {
   HARDIRQ-ON-W at:
                    [<8005f030>] mark_lock+0x140/0x6ac
                    [<8005f604>] mark_held_locks+0x68/0x12c
                    [<8005f780>] trace_hardirqs_on_caller+0xb8/0x1d8
                    [<8005f8b4>] trace_hardirqs_on+0x14/0x18
                    [<8061a130>] mutex_trylock+0x180/0x20c
                    [<80480ad8>] clk_prepare_lock+0x14/0xe4
                    [<804816a4>] clk_notifier_register+0x28/0xf0
                    [<80015120>] twd_clk_init+0x50/0x68
                    [<80008980>] do_one_initcall+0x108/0x16c
                    [<8081cca4>] kernel_init_freeable+0x10c/0x1d0
                    [<80611c50>] kernel_init+0x10/0x120
                    [<8000e9c8>] ret_from_fork+0x14/0x2c
   SOFTIRQ-ON-W at:
                    [<8005f030>] mark_lock+0x140/0x6ac
                    [<8005f604>] mark_held_locks+0x68/0x12c
                    [<8005f7c8>] trace_hardirqs_on_caller+0x100/0x1d8
                    [<8005f8b4>] trace_hardirqs_on+0x14/0x18
                    [<8061a130>] mutex_trylock+0x180/0x20c
                    [<80480ad8>] clk_prepare_lock+0x14/0xe4
                    [<804816a4>] clk_notifier_register+0x28/0xf0
                    [<80015120>] twd_clk_init+0x50/0x68
                    [<80008980>] do_one_initcall+0x108/0x16c
                    [<8081cca4>] kernel_init_freeable+0x10c/0x1d0
                    [<80611c50>] kernel_init+0x10/0x120
                    [<8000e9c8>] ret_from_fork+0x14/0x2c
   INITIAL USE at:
                   [<8005f030>] mark_lock+0x140/0x6ac
                   [<8005ff0c>] __lock_acquire+0x2dc/0x1cbc
                   [<800620d0>] lock_acquire+0x70/0x84
                   [<8061a0c8>] mutex_trylock+0x118/0x20c
                   [<80480ad8>] clk_prepare_lock+0x14/0xe4
                   [<80482af8>] __clk_init+0x1c/0x45c
                   [<8048306c>] _clk_register+0xd0/0x170
                   [<80483148>] clk_register+0x3c/0x7c
                   [<80483b4c>] clk_register_fixed_rate+0x88/0xd8
                   [<80483c04>] of_fixed_clk_setup+0x68/0x94
                   [<8084c6fc>] of_clk_init+0x44/0x68
                   [<808202b0>] time_init+0x2c/0x38
                   [<8081ca14>] start_kernel+0x1e4/0x368
                   [<10008074>] 0x10008074
 }
 ... key      at: [<808afebc>] prepare_lock+0x38/0x48
 ... acquired at:
   [<8005eb94>] check_usage+0x404/0x5c0
   [<8005edac>] check_irq_usage+0x5c/0xb8
   [<80060d38>] __lock_acquire+0x1108/0x1cbc
   [<800620d0>] lock_acquire+0x70/0x84
   [<8061a210>] mutex_lock_nested+0x54/0x3c0
   [<80480b08>] clk_prepare_lock+0x44/0xe4
   [<8048188c>] clk_get_rate+0x14/0x64
   [<8046374c>] esdhc_pltfm_set_clock+0x20/0x2a4
   [<8045d70c>] sdhci_set_clock+0x4c/0x498
   [<80461518>] sdhci_do_set_ios+0x344/0x720
   [<80461924>] sdhci_set_ios+0x30/0x3c
   [<8044c390>] __mmc_set_clock+0x44/0x60
   [<8044cd4c>] mmc_set_clock+0x10/0x14
   [<8044f8f4>] mmc_init_card+0x1b4/0x1520
   [<80450f00>] mmc_attach_mmc+0xb4/0x194
   [<8044da08>] mmc_rescan+0x294/0x2f0
   [<8003db94>] process_one_work+0x1a4/0x468
   [<8003e850>] worker_thread+0x118/0x3e0
   [<80044de0>] kthread+0xd4/0xf0
   [<8000e9c8>] ret_from_fork+0x14/0x2c

stack backtrace:
CPU: 2 PID: 29 Comm: kworker/u8:1 Not tainted 3.13.0-rc1+ torvalds#285
Workqueue: kmmcd mmc_rescan
Backtrace:
[<80012160>] (dump_backtrace+0x0/0x10c) from [<80012438>] (show_stack+0x18/0x1c)
 r6:00000000 r5:00000000 r4:8088ecc8 r3:bfa11200
[<80012420>] (show_stack+0x0/0x1c) from [<80616b14>] (dump_stack+0x84/0x9c)
[<80616a90>] (dump_stack+0x0/0x9c) from [<8005ebb4>] (check_usage+0x424/0x5c0)
 r5:80979940 r4:bfa29b44
[<8005e790>] (check_usage+0x0/0x5c0) from [<8005edac>] (check_irq_usage+0x5c/0xb8)
[<8005ed50>] (check_irq_usage+0x0/0xb8) from [<80060d38>] (__lock_acquire+0x1108/0x1cbc)
 r8:bfa115e8 r7:80df9884 r6:80dafa9c r5:00000003 r4:bfa115d0
[<8005fc30>] (__lock_acquire+0x0/0x1cbc) from [<800620d0>] (lock_acquire+0x70/0x84)
[<80062060>] (lock_acquire+0x0/0x84) from [<8061a210>] (mutex_lock_nested+0x54/0x3c0)
 r7:bfa11200 r6:80dafa9c r5:00000000 r4:80480b08
[<8061a1bc>] (mutex_lock_nested+0x0/0x3c0) from [<80480b08>] (clk_prepare_lock+0x44/0xe4)
[<80480ac4>] (clk_prepare_lock+0x0/0xe4) from [<8048188c>] (clk_get_rate+0x14/0x64)
 r6:03197500 r5:bf0e9aa8 r4:bf827400 r3:808ae128
[<80481878>] (clk_get_rate+0x0/0x64) from [<8046374c>] (esdhc_pltfm_set_clock+0x20/0x2a4)
 r5:bf0e9aa8 r4:bf0e9c40
[<8046372c>] (esdhc_pltfm_set_clock+0x0/0x2a4) from [<8045d70c>] (sdhci_set_clock+0x4c/0x498)
[<8045d6c0>] (sdhci_set_clock+0x0/0x498) from [<80461518>] (sdhci_do_set_ios+0x344/0x720)
 r8:0000003b r7:20000113 r6:bf0e9d68 r5:bf0e9aa8 r4:bf0e9c40
r3:00000000
[<804611d4>] (sdhci_do_set_ios+0x0/0x720) from [<80461924>] (sdhci_set_ios+0x30/0x3c)
 r9:00000004 r8:bf131000 r7:bf131048 r6:00000000 r5:bf0e9aa8
r4:bf0e9800
[<804618f4>] (sdhci_set_ios+0x0/0x3c) from [<8044c390>] (__mmc_set_clock+0x44/0x60)
 r5:03197500 r4:bf0e9800
[<8044c34c>] (__mmc_set_clock+0x0/0x60) from [<8044cd4c>] (mmc_set_clock+0x10/0x14)
 r5:00000000 r4:bf0e9800
[<8044cd3c>] (mmc_set_clock+0x0/0x14) from [<8044f8f4>] (mmc_init_card+0x1b4/0x1520)
[<8044f740>] (mmc_init_card+0x0/0x1520) from [<80450f00>] (mmc_attach_mmc+0xb4/0x194)
[<80450e4c>] (mmc_attach_mmc+0x0/0x194) from [<8044da08>] (mmc_rescan+0x294/0x2f0)
 r5:8065f358 r4:bf0e9af8
[<8044d774>] (mmc_rescan+0x0/0x2f0) from [<8003db94>] (process_one_work+0x1a4/0x468)
 r8:00000000 r7:bfa29eb0 r6:bf80dc00 r5:bf0e9af8 r4:bf9e3f00
r3:8044d774
[<8003d9f0>] (process_one_work+0x0/0x468) from [<8003e850>] (worker_thread+0x118/0x3e0)
[<8003e738>] (worker_thread+0x0/0x3e0) from [<80044de0>] (kthread+0xd4/0xf0)
[<80044d0c>] (kthread+0x0/0xf0) from [<8000e9c8>] (ret_from_fork+0x14/0x2c)
 r7:00000000 r6:00000000 r5:80044d0c r4:bf9e7f00

Fixes: 0ddf03c mmc: esdhc-imx: parse max-frequency from devicetree
Signed-off-by: Dong Aisheng <[email protected]>
Acked-by: Shawn Guo <[email protected]>
Tested-by: Philippe De Muyter <[email protected]>
Cc: stable <[email protected]> # 3.13
Signed-off-by: Chris Ball <[email protected]>
tom3q pushed a commit that referenced this pull request Mar 4, 2014
In https://bugzilla.kernel.org/show_bug.cgi?id=67561, a locking dependency is reported
when b43 is used with hostapd, and rfkill is used to kill the radio output.

The lockdep splat (in part) is as follows:

======================================================
[ INFO: possible circular locking dependency detected ]
3.12.0 #1 Not tainted
-------------------------------------------------------
rfkill/10040 is trying to acquire lock:
 (rtnl_mutex){+.+.+.}, at: [<ffffffff8146f282>] rtnl_lock+0x12/0x20

but task is already holding lock:
 (rfkill_global_mutex){+.+.+.}, at: [<ffffffffa04832ca>] rfkill_fop_write+0x6a/0x170 [rfkill]

--snip--

Chain exists of:
  rtnl_mutex --> misc_mtx --> rfkill_global_mutex

The fix is to move the initialization of the hardware random number generator
outside the code range covered by the rtnl_mutex.

Reported-by: yury <[email protected]>
Tested-by: yury <[email protected]>
Signed-off-by: Larry Finger <[email protected]>
Cc: Stable <[email protected]>
Signed-off-by: John W. Linville <[email protected]>
tom3q pushed a commit that referenced this pull request Mar 4, 2014
* init the sts flag to 0 (missed)
* fix write the real bit not sts value
* Set PORTCS_STS and DEVLC_STS only if sts = 1

[Peter Chen: This one and the next patch fix the problem occurred imx27
and imx31, and imx27 and imx31 usb support are enabled until 3.14, so
these two patches isn't needed for -stable]

Signed-off-by: Chris Ruehl <[email protected]>
Signed-off-by: Peter Chen <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
tom3q pushed a commit that referenced this pull request Mar 4, 2014
Avoid circular mutex lock by pushing the dev->lock to the .fini
callback on each extension.

As em28xx-dvb, em28xx-alsa and em28xx-rc have their own data
structures, and don't touch at the common structure during .fini,
only em28xx-v4l needs to be locked.

[   90.994317] ======================================================
[   90.994356] [ INFO: possible circular locking dependency detected ]
[   90.994395] 3.13.0-rc1+ torvalds#24 Not tainted
[   90.994427] -------------------------------------------------------
[   90.994458] khubd/54 is trying to acquire lock:
[   90.994490]  (&card->controls_rwsem){++++.+}, at: [<ffffffffa0177b08>] snd_ctl_dev_free+0x28/0x60 [snd]
[   90.994656]
[   90.994656] but task is already holding lock:
[   90.994688]  (&dev->lock){+.+.+.}, at: [<ffffffffa040db81>] em28xx_close_extension+0x31/0x90 [em28xx]
[   90.994843]
[   90.994843] which lock already depends on the new lock.
[   90.994843]
[   90.994874]
[   90.994874] the existing dependency chain (in reverse order) is:
[   90.994905]
-> #1 (&dev->lock){+.+.+.}:
[   90.995057]        [<ffffffff810b8fa3>] __lock_acquire+0xb43/0x1330
[   90.995121]        [<ffffffff810b9f82>] lock_acquire+0xa2/0x120
[   90.995182]        [<ffffffff816a5b6c>] mutex_lock_nested+0x5c/0x3c0
[   90.995245]        [<ffffffffa0422cca>] em28xx_vol_put_mute+0x1ba/0x1d0 [em28xx_alsa]
[   90.995309]        [<ffffffffa017813d>] snd_ctl_elem_write+0xfd/0x140 [snd]
[   90.995376]        [<ffffffffa01791c2>] snd_ctl_ioctl+0xe2/0x810 [snd]
[   90.995442]        [<ffffffff811db8b0>] do_vfs_ioctl+0x300/0x520
[   90.995504]        [<ffffffff811dbb51>] SyS_ioctl+0x81/0xa0
[   90.995568]        [<ffffffff816b1929>] system_call_fastpath+0x16/0x1b
[   90.995630]
-> #0 (&card->controls_rwsem){++++.+}:
[   90.995780]        [<ffffffff810b7a47>] check_prevs_add+0x947/0x950
[   90.995841]        [<ffffffff810b8fa3>] __lock_acquire+0xb43/0x1330
[   90.995901]        [<ffffffff810b9f82>] lock_acquire+0xa2/0x120
[   90.995962]        [<ffffffff816a762b>] down_write+0x3b/0xa0
[   90.996022]        [<ffffffffa0177b08>] snd_ctl_dev_free+0x28/0x60 [snd]
[   90.996088]        [<ffffffffa017a255>] snd_device_free+0x65/0x140 [snd]
[   90.996154]        [<ffffffffa017a751>] snd_device_free_all+0x61/0xa0 [snd]
[   90.996219]        [<ffffffffa0173af4>] snd_card_do_free+0x14/0x130 [snd]
[   90.996283]        [<ffffffffa0173f14>] snd_card_free+0x84/0x90 [snd]
[   90.996349]        [<ffffffffa0423397>] em28xx_audio_fini+0x97/0xb0 [em28xx_alsa]
[   90.996411]        [<ffffffffa040dba6>] em28xx_close_extension+0x56/0x90 [em28xx]
[   90.996475]        [<ffffffffa040f639>] em28xx_usb_disconnect+0x79/0x90 [em28xx]
[   90.996539]        [<ffffffff814a06e7>] usb_unbind_interface+0x67/0x1d0
[   90.996620]        [<ffffffff8142920f>] __device_release_driver+0x7f/0xf0
[   90.996682]        [<ffffffff814292a5>] device_release_driver+0x25/0x40
[   90.996742]        [<ffffffff81428b0c>] bus_remove_device+0x11c/0x1a0
[   90.996801]        [<ffffffff81425536>] device_del+0x136/0x1d0
[   90.996863]        [<ffffffff8149e0c0>] usb_disable_device+0xb0/0x290
[   90.996923]        [<ffffffff814930c5>] usb_disconnect+0xb5/0x1d0
[   90.996984]        [<ffffffff81495ab6>] hub_port_connect_change+0xd6/0xad0
[   90.997044]        [<ffffffff814967c3>] hub_events+0x313/0x9b0
[   90.997105]        [<ffffffff81496e95>] hub_thread+0x35/0x170
[   90.997165]        [<ffffffff8108ea2f>] kthread+0xff/0x120
[   90.997226]        [<ffffffff816b187c>] ret_from_fork+0x7c/0xb0
[   90.997287]
[   90.997287] other info that might help us debug this:
[   90.997287]
[   90.997318]  Possible unsafe locking scenario:
[   90.997318]
[   90.997348]        CPU0                    CPU1
[   90.997378]        ----                    ----
[   90.997408]   lock(&dev->lock);
[   90.997497]                                lock(&card->controls_rwsem);
[   90.997607]                                lock(&dev->lock);
[   90.997697]   lock(&card->controls_rwsem);
[   90.997786]
[   90.997786]  *** DEADLOCK ***
[   90.997786]
[   90.997817] 5 locks held by khubd/54:
[   90.997847]  #0:  (&__lockdep_no_validate__){......}, at: [<ffffffff81496564>] hub_events+0xb4/0x9b0
[   90.998025]  #1:  (&__lockdep_no_validate__){......}, at: [<ffffffff81493076>] usb_disconnect+0x66/0x1d0
[   90.998204]  #2:  (&__lockdep_no_validate__){......}, at: [<ffffffff8142929d>] device_release_driver+0x1d/0x40
[   90.998383]  #3:  (em28xx_devlist_mutex){+.+.+.}, at: [<ffffffffa040db77>] em28xx_close_extension+0x27/0x90 [em28xx]
[   90.998567]  #4:  (&dev->lock){+.+.+.}, at: [<ffffffffa040db81>] em28xx_close_extension+0x31/0x90 [em28xx]

Reviewed-by: Frank Schäfer <[email protected]>
Tested-by: Antti Palosaari <[email protected]>
Signed-off-by: Mauro Carvalho Chehab <[email protected]>
tom3q pushed a commit that referenced this pull request Mar 4, 2014
Paul Durrant says:

====================
make skb_checksum_setup generally available

Both xen-netfront and xen-netback need to be able to set up the partial
checksum offset of an skb and may also need to recalculate the pseudo-
header checksum in the process. This functionality is currently private
and duplicated between the two drivers.

Patch #1 of this series moves the implementation into the core network code
as there is nothing xen-specific about it and it is potentially useful to
any network driver.
Patch #2 removes the private implementation from netback.
Patch #3 removes the private implementation from netfront.

v2:
- Put skb_checksum_setup in skbuff.c rather than dev.c
- remove inline
====================

Signed-off-by: David S. Miller <[email protected]>
tom3q pushed a commit that referenced this pull request Oct 2, 2014
…heck

If the type we receive is greater than ST_MAX_CHANNELS we can't rely on
type as vector index since we would be accessing unknown memory when we use the type
as index.

 Unable to handle kernel NULL pointer dereference at virtual address 0000001b
 pgd = c0004000
 [0000001b] *pgd=00000000
 Internal error: Oops: 17 [#1] PREEMPT SMP ARM
 Modules linked in: btwilink wl12xx wlcore mac80211 cfg80211 rfcomm bnep bluo
 CPU: 0    Tainted: G        W     (3.4.0+ torvalds#15)
 PC is at st_int_recv+0x278/0x344
 LR is at get_parent_ip+0x14/0x30
 pc : [<c03b01a8>]    lr : [<c007273c>]    psr: 200f0193
 sp : dc631ed0  ip : e3e21c24  fp : dc631f04
 r10: 00000000  r9 : 600f0113  r8 : 0000003f
 r7 : e3e21b14  r6 : 00000067  r5 : e2e49c1c  r4 : e3e21a80
 r3 : 00000001  r2 : 00000001  r1 : 00000001  r0 : 600f0113
 Flags: nzCv  IRQs off  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
 Control: 10c5387d  Table: 9c50004a  DAC: 00000015

Signed-off-by: Gustavo Padovan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
tom3q pushed a commit that referenced this pull request Oct 2, 2014
…el-gauge

NULL pointer exception happens during charger-manager probe if
'cm-fuel-gauge' property is not present.

[    2.448536] Unable to handle kernel NULL pointer dereference at virtual address 00000000
[    2.456572] pgd = c0004000
[    2.459217] [00000000] *pgd=00000000
[    2.462759] Internal error: Oops: 5 [#1] PREEMPT SMP ARM
[    2.468047] Modules linked in:
[    2.471089] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.17.0-rc6-00251-ge44cf96cd525-dirty torvalds#969
[    2.479765] task: ea890000 ti: ea87a000 task.ti: ea87a000
[    2.485161] PC is at strcmp+0x4/0x30
[    2.488719] LR is at power_supply_match_device_by_name+0x10/0x1c
[    2.494695] pc : [<c01f4220>]    lr : [<c030fe38>]    psr: a0000113
[    2.494695] sp : ea87bde0  ip : 00000000  fp : eaa97010
[    2.506150] r10: 00000004  r9 : ea97269c  r8 : ea3bbfd0
[    2.511360] r7 : eaa97000  r6 : c030fe28  r5 : 00000000  r4 : ea3b0000
[    2.517869] r3 : 0000006d  r2 : 00000000  r1 : 00000000  r0 : c057c195
[    2.524381] Flags: NzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
[    2.531671] Control: 10c5387d  Table: 4000404a  DAC: 00000015
[    2.537399] Process swapper/0 (pid: 1, stack limit = 0xea87a240)
[    2.543388] Stack: (0xea87bde0 to 0xea87c000)
[    2.547733] bde0: ea3b0210 c026b1c8 eaa97010 eaa97000 eaa97010 eabb60a8 ea3b0210 00000000
[    2.555891] be00: 00000008 ea2db210 ea1a3410 c030fee0 ea3bbf90 c03138fc c068969c c013526c
[    2.564050] be20: eaa040c0 00000000 c068969c 00000000 eaa040c0 ea2da300 00000002 00000000
[    2.572208] be40: 00000001 ea2da3c0 00000000 00000001 00000000 eaa97010 c068969c 00000000
[    2.580367] be60: 00000000 c068969c 00000000 00000002 00000000 c026b71c c026b6f0 eaa97010
[    2.588527] be80: c0e82530 c026a330 00000000 eaa97010 c068969c eaa97044 00000000 c061df50
[    2.596686] bea0: ea87a000 c026a4dc 00000000 c068969c c026a448 c0268b5c ea8054a8 eaa8fd50
[    2.604845] bec0: c068969c ea2db180 c06801f8 c0269b18 c0590f68 c068969c c0656c98 c068969c
[    2.613004] bee0: c0656c98 ea3bbe40 c06988c0 c026aaf0 00000000 c0656c98 c0656c98 c00088a4
[    2.621163] bf00: 00000000 c0055f48 00000000 00000004 00000000 ea890000 c05dbc54 c062c178
[    2.629323] bf20: c0603518 c005f674 00000001 ea87a000 eb7ff83b c0476440 00000091 c003d41c
[    2.637482] bf40: c05db344 00000007 eb7ff858 00000007 c065a76c c0647d24 00000007 c062c170
[    2.645642] bf60: c06988c0 00000091 c062c178 c0603518 00000000 c0603cc4 00000007 00000007
[    2.653801] bf80: c0603518 c0c0c0c0 00000000 c0453948 00000000 00000000 00000000 00000000
[    2.661959] bfa0: 00000000 c0453950 00000000 c000e728 00000000 00000000 00000000 00000000
[    2.670118] bfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
[    2.678277] bfe0: 00000000 00000000 00000000 00000000 00000013 00000000 c0c0c0c0 c0c0c0c0
[    2.686454] [<c01f4220>] (strcmp) from [<c030fe38>] (power_supply_match_device_by_name+0x10/0x1c)
[    2.695303] [<c030fe38>] (power_supply_match_device_by_name) from [<c026b1c8>] (class_find_device+0x54/0xac)
[    2.705106] [<c026b1c8>] (class_find_device) from [<c030fee0>] (power_supply_get_by_name+0x1c/0x30)
[    2.714137] [<c030fee0>] (power_supply_get_by_name) from [<c03138fc>] (charger_manager_probe+0x3d8/0xe58)
[    2.723683] [<c03138fc>] (charger_manager_probe) from [<c026b71c>] (platform_drv_probe+0x2c/0x5c)
[    2.732532] [<c026b71c>] (platform_drv_probe) from [<c026a330>] (driver_probe_device+0x10c/0x224)
[    2.741384] [<c026a330>] (driver_probe_device) from [<c026a4dc>] (__driver_attach+0x94/0x98)
[    2.749813] [<c026a4dc>] (__driver_attach) from [<c0268b5c>] (bus_for_each_dev+0x54/0x88)
[    2.757969] [<c0268b5c>] (bus_for_each_dev) from [<c0269b18>] (bus_add_driver+0xd4/0x1d0)
[    2.766123] [<c0269b18>] (bus_add_driver) from [<c026aaf0>] (driver_register+0x78/0xf4)
[    2.774110] [<c026aaf0>] (driver_register) from [<c00088a4>] (do_one_initcall+0x80/0x1bc)
[    2.782276] [<c00088a4>] (do_one_initcall) from [<c0603cc4>] (kernel_init_freeable+0x100/0x1cc)
[    2.790952] [<c0603cc4>] (kernel_init_freeable) from [<c0453950>] (kernel_init+0x8/0xec)
[    2.799029] [<c0453950>] (kernel_init) from [<c000e728>] (ret_from_fork+0x14/0x2c)
[    2.806572] Code: e12fff1e e1a03000 eafffff7 e4d03001 (e4d12001)
[    2.812832] ---[ end trace 7f12556111b9e7ef ]---

Signed-off-by: Krzysztof Kozlowski <[email protected]>
Cc: <[email protected]>
Fixes: 856ee61 ("charger-manager: Support deivce tree in charger manager driver")
Signed-off-by: Sebastian Reichel <[email protected]>
tom3q pushed a commit that referenced this pull request Oct 2, 2014
The serial8250_do_startup() function unconditionally clears the
interrupts and for that it reads from the RX-FIFO without checking if
there is a byte in the FIFO or not. This works fine on OMAP4+ HW like
AM335x or DRA7.
OMAP3630 ES1.1 (which means probably all OMAP3 and earlier) does not like
this:

|Unhandled fault: external abort on non-linefetch (0x1028) at 0xfb020000
|Internal error: : 1028 [#1] ARM
|Modules linked in:
|CPU: 0 PID: 1 Comm: swapper Not tainted 3.16.0-00022-g7edcb57-dirty #1213
|task: de0572c0 ti: de058000 task.ti: de058000
|PC is at mem32_serial_in+0xc/0x1c
|LR is at serial8250_do_startup+0x220/0x85c
|Flags: nzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
|Control: 10c5387d  Table: 80004019  DAC: 00000015
|[<c03051d4>] (mem32_serial_in) from [<c0307fe8>] (serial8250_do_startup+0x220/0x85c)
|[<c0307fe8>] (serial8250_do_startup) from [<c0309e00>] (omap_8250_startup+0x5c/0xe0)
|[<c0309e00>] (omap_8250_startup) from [<c030863c>] (serial8250_startup+0x18/0x2c)
|[<c030863c>] (serial8250_startup) from [<c030394c>] (uart_startup+0x78/0x1d8)
|[<c030394c>] (uart_startup) from [<c0304678>] (uart_open+0xe8/0x114)
|[<c0304678>] (uart_open) from [<c02e9e10>] (tty_open+0x1a8/0x5a4)

Reviewed-by: Tony Lindgren <[email protected]>
Tested-by: Tony Lindgren <[email protected]>
Signed-off-by: Sebastian Andrzej Siewior <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
tom3q pushed a commit that referenced this pull request Oct 2, 2014
1.
the library includes a trivial set of BPF syscall wrappers:
int bpf_create_map(int key_size, int value_size, int max_entries);
int bpf_update_elem(int fd, void *key, void *value);
int bpf_lookup_elem(int fd, void *key, void *value);
int bpf_delete_elem(int fd, void *key);
int bpf_get_next_key(int fd, void *key, void *next_key);
int bpf_prog_load(enum bpf_prog_type prog_type,
		  const struct sock_filter_int *insns, int insn_len,
		  const char *license);
bpf_prog_load() stores verifier log into global bpf_log_buf[] array

and BPF_*() macros to build instructions

2.
test stubs configure eBPF infra with 'unspec' map and program types.
These are fake types used by user space testsuite only.

3.
verifier tests valid and invalid programs and expects predefined
error log messages from kernel.
40 tests so far.

$ sudo ./test_verifier
 #0 add+sub+mul OK
 #1 unreachable OK
 #2 unreachable2 OK
 #3 out of range jump OK
 #4 out of range jump2 OK
 #5 test1 ld_imm64 OK
 ...

Signed-off-by: Alexei Starovoitov <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
tom3q pushed a commit that referenced this pull request Oct 2, 2014
The current driver loss Ftype field init for BD, which cause tx
queue #1 and #2 cannot work well.

Add Ftype field to BD to distiguish three queues for AVB:
0 -> Best Effort
1 -> ClassA
2 -> ClassB

Signed-off-by: Fugang Duan <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
tom3q pushed a commit that referenced this pull request Oct 2, 2014
…ation

If we fail to create our mmu notification, we report the error back and
currently store the error inside the i915_mm_struct. This not only causes
subsequent registerations of the same mm to fail (an issue if the first
was interrupted by a signal and needed to be restarted) but also causes
us to eventually try and free the error pointer.

[   73.419599] BUG: unable to handle kernel NULL pointer dereference at 000000000000004c
[   73.419831] IP: [<ffffffff8114af33>] mmu_notifier_unregister+0x23/0x130
[   73.420065] PGD 8650c067 PUD 870bb067 PMD 0
[   73.420319] Oops: 0000 [#1] SMP DEBUG_PAGEALLOC
[   73.420580] CPU: 0 PID: 42 Comm: kworker/0:1 Tainted: G        W      3.17.0-rc6+ #1561
[   73.420837] Hardware name: Intel Corporation SandyBridge Platform/LosLunas CRB, BIOS ASNBCPT1.86C.0075.P00.1106281639 06/28/2011
[   73.421405] Workqueue: events __i915_mm_struct_free__worker
[   73.421724] task: ffff880088a81220 ti: ffff880088168000 task.ti: ffff880088168000
[   73.422051] RIP: 0010:[<ffffffff8114af33>]  [<ffffffff8114af33>] mmu_notifier_unregister+0x23/0x130
[   73.422410] RSP: 0018:ffff88008816bd50  EFLAGS: 00010286
[   73.422765] RAX: 0000000000000003 RBX: ffff880086485400 RCX: 0000000000000000
[   73.423137] RDX: ffff88016d80ee90 RSI: ffff880086485400 RDI: 0000000000000044
[   73.423513] RBP: ffff88008816bd70 R08: 0000000000000001 R09: 0000000000000000
[   73.423895] R10: 0000000000000320 R11: 0000000000000001 R12: 0000000000000044
[   73.424282] R13: ffff880166e5f008 R14: ffff88016d815200 R15: ffff880166e5f040
[   73.424682] FS:  0000000000000000(0000) GS:ffff88016d800000(0000) knlGS:0000000000000000
[   73.425099] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   73.425537] CR2: 000000000000004c CR3: 0000000087f5f000 CR4: 00000000000407f0
[   73.426157] Stack:
[   73.426597]  ffff880088a81248 ffff880166e5f038 fffffffffffffffc ffff880166e5f008
[   73.427096]  ffff88008816bd98 ffffffff814a75f2 ffff880166e5f038 ffff8800880f8a28
[   73.427603]  ffff88016d812ac0 ffff88008816be00 ffffffff8106321a ffffffff810631af
[   73.428119] Call Trace:
[   73.428606]  [<ffffffff814a75f2>] __i915_mm_struct_free__worker+0x42/0x80
[   73.429116]  [<ffffffff8106321a>] process_one_work+0x1ba/0x610
[   73.429632]  [<ffffffff810631af>] ? process_one_work+0x14f/0x610
[   73.430153]  [<ffffffff810636db>] worker_thread+0x6b/0x4a0
[   73.430671]  [<ffffffff8108d67d>] ? trace_hardirqs_on+0xd/0x10
[   73.431501]  [<ffffffff81063670>] ? process_one_work+0x610/0x610
[   73.432030]  [<ffffffff8106a206>] kthread+0xf6/0x110
[   73.432561]  [<ffffffff8106a110>] ? __kthread_parkme+0x80/0x80
[   73.433100]  [<ffffffff8169c22c>] ret_from_fork+0x7c/0xb0
[   73.433644]  [<ffffffff8106a110>] ? __kthread_parkme+0x80/0x80
[   73.434194] Code: 0f 1f 84 00 00 00 00 00 66 66 66 66 90 8b 46 4c 85 c0 0f 8e 10 01 00 00 55 48 89 e5 41 55 41 54 53 48 89 f3 49 89 fc 48 83 ec 08 <48> 83 7f 08 00 0f 84 b1 00 00 00 48 c7 c7 40 e6 ac 82 e8 26 65
[   73.435942] RIP  [<ffffffff8114af33>] mmu_notifier_unregister+0x23/0x130
[   73.437017]  RSP <ffff88008816bd50>
[   73.437704] CR2: 000000000000004c

Fixes regression from commit ad46cb5
Author: Chris Wilson <[email protected]>
Date:   Thu Aug 7 14:20:40 2014 +0100

    drm/i915: Prevent recursive deadlock on releasing a busy userptr

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=84207
Testcase: igt/gem_render_copy_redux
Testcase: igt/gem_userptr_blits/create-destroy-sync
Signed-off-by: Chris Wilson <[email protected]>
Cc: Jacek Danecki <[email protected]>
Cc: "Gong, Zhipeng" <[email protected]>
Cc: Jacek Danecki <[email protected]>
Cc: "Ursulin, Tvrtko" <[email protected]>
Cc: [email protected]
Reviewed-by: Tvrtko Ursulin <[email protected]>
Signed-off-by: Daniel Vetter <[email protected]>
tom3q pushed a commit that referenced this pull request Oct 2, 2014
The other two interrupt handlers in this driver are shared, except this
one. When loading the driver, it fails like this.

So make the IRQ line shared.

Freescale(R) MPC85xx EDAC driver, (C) 2006 Montavista Software
mpc85xx_mc_err_probe: No ECC DIMMs discovered
EDAC DEVICE0: Giving out device to module MPC85xx_edac controller mpc85xx_l2_err: DEV mpc85xx_l2_err (INTERRUPT)
genirq: Flags mismatch irq 16. 00000000 ([EDAC] L2 err) vs. 00000080 ([EDAC] PCI err)
mpc85xx_l2_err_probe: Unable to request irq 16 for MPC85xx L2 err
remove_proc_entry: removing non-empty directory 'irq/16', leaking at least 'aerdrv'
------------[ cut here ]------------
WARNING: at fs/proc/generic.c:521
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.17.0-rc5-dirty #1
task: ee058000 ti: ee046000 task.ti: ee046000
NIP: c016c0c4 LR: c016c0c4 CTR: c037b51
REGS: ee047c10 TRAP: 0700 Not tainted (3.17.0-rc5-dirty)
MSR: 00029000 <CE,EE,ME> CR: 22008022 XER: 20000000

GPR00: c016c0c4 ee047cc0 ee058000 00000053 00029000 00000000 c037c744 00000003
GPR08: c09aab28 c09aab24 c09aab28 00000156 20008028 00000000 c0002ac 00000000
GPR16: 00000000 00000000 00000000 00000000 00000000 00000000 00000139 c0950394
GPR24: c09f0000 ee5585b0 ee047d08 c0a10000 ee047d08 ee15f808 00000002 ee03f660
NIP [c016c0c4] remove_proc_entry
LR [c016c0c4] remove_proc_entry
Call Trace:
remove_proc_entry (unreliable)
unregister_irq_proc
free_desc
irq_free_descs
mpc85xx_l2_err_probe
platform_drv_probe
really_probe
__driver_attach
bus_for_each_dev
bus_add_driver
driver_register
mpc85xx_mc_init
do_one_initcall
kernel_init_freeable
kernel_init
ret_from_kernel_thread
Instruction dump: ...

Reported-and-tested-by: <[email protected]>
Acked-by: Johannes Thumshirn <[email protected]>
Cc: [email protected]
Signed-off-by: Borislav Petkov <[email protected]>
tom3q pushed a commit that referenced this pull request Oct 2, 2014
blkback does not unmap persistent grants when frontend goes to Closed
state (e.g. when blkfront module is being removed). This leads to the
following in guest's dmesg:

[  343.243825] xen:grant_table: WARNING: g.e. 0x445 still in use!
[  343.243825] xen:grant_table: WARNING: g.e. 0x42a still in use!
...

When load module -> use device -> unload module sequence is performed multiple times
it is possible to hit BUG() condition in blkfront module:

[  343.243825] kernel BUG at drivers/block/xen-blkfront.c:954!
[  343.243825] invalid opcode: 0000 [#1] SMP
[  343.243825] Modules linked in: xen_blkfront(-) ata_generic pata_acpi [last unloaded: xen_blkfront]
...
[  343.243825] Call Trace:
[  343.243825]  [<ffffffff814111ef>] ? unregister_xenbus_watch+0x16f/0x1e0
[  343.243825]  [<ffffffffa0016fbf>] blkfront_remove+0x3f/0x140 [xen_blkfront]
...
[  343.243825] RIP  [<ffffffffa0016aae>] blkif_free+0x34e/0x360 [xen_blkfront]
[  343.243825]  RSP <ffff88001eb8fdc0>

We don't need to keep these grants if we're disconnecting as frontend might already
forgot about them. Solve the issue by moving xen_blkbk_free_caches() call from
xen_blkif_free() to xen_blkif_disconnect().

Now we can see the following:
[  928.590893] xen:grant_table: WARNING: g.e. 0x587 still in use!
[  928.591861] xen:grant_table: WARNING: g.e. 0x372 still in use!
...
[  929.592146] xen:grant_table: freeing g.e. 0x587
[  929.597174] xen:grant_table: freeing g.e. 0x372
...

Backend does not keep persistent grants any more, reconnect works fine.

CC: [email protected]
Signed-off-by: Vitaly Kuznetsov <[email protected]>
Signed-off-by: Konrad Rzeszutek Wilk <[email protected]>
tom3q pushed a commit that referenced this pull request Oct 7, 2014
Alexei Starovoitov says:

====================
bpf: add search pruning optimization and tests

patch #1 commit log explains why eBPF verifier has to examine some
instructions multiple times and describes the search pruning optimization
that improves verification speed for branchy programs and allows more
complex programs to be verified successfully.
This patch completes the core verifier logic.

patch #2 adds more verifier tests related to branches and search pruning

I'm still working on Andy's 'bitmask for stack slots' suggestion. It will be
done on top of this patch.

The current verifier algorithm is brute force depth first search with
state pruning. If anyone can come up with another algorithm that demonstrates
better results, we'll replace the algorithm without affecting user space.

Note verifier doesn't guarantee that all possible valid programs are accepted.
Overly complex programs may still be rejected.
Verifier improvements/optimizations will guarantee that if a program
was passing verification in the past, it will still be passing.
====================

Signed-off-by: David S. Miller <[email protected]>
tom3q pushed a commit that referenced this pull request Oct 7, 2014
This patch fixes the following crash:

[  166.670795] BUG: unable to handle kernel NULL pointer dereference at           (null)
[  166.674230] IP: [<ffffffff814b739f>] __list_del_entry+0x5c/0x98
[  166.674230] PGD d0ea5067 PUD ce7fc067 PMD 0
[  166.674230] Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
[  166.674230] CPU: 1 PID: 775 Comm: tc Not tainted 3.17.0-rc6+ torvalds#642
[  166.674230] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[  166.674230] task: ffff8800d03c4d20 ti: ffff8800cae7c000 task.ti: ffff8800cae7c000
[  166.674230] RIP: 0010:[<ffffffff814b739f>]  [<ffffffff814b739f>] __list_del_entry+0x5c/0x98
[  166.674230] RSP: 0018:ffff8800cae7f7d0  EFLAGS: 00010207
[  166.674230] RAX: 0000000000000000 RBX: ffff8800cba8d700 RCX: ffff8800cba8d700
[  166.674230] RDX: 0000000000000000 RSI: dead000000200200 RDI: ffff8800cba8d700
[  166.674230] RBP: ffff8800cae7f7d0 R08: 0000000000000001 R09: 0000000000000001
[  166.674230] R10: 0000000000000000 R11: 000000000000859a R12: ffffffffffffffe8
[  166.674230] R13: ffff8800cba8c5b8 R14: 0000000000000001 R15: ffff8800cba8d700
[  166.674230] FS:  00007fdb5f04a740(0000) GS:ffff88011a800000(0000) knlGS:0000000000000000
[  166.674230] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[  166.674230] CR2: 0000000000000000 CR3: 00000000cf929000 CR4: 00000000000006e0
[  166.674230] Stack:
[  166.674230]  ffff8800cae7f7e8 ffffffff814b73e8 ffff8800cba8d6e8 ffff8800cae7f828
[  166.674230]  ffffffff817caeec 0000000000000046 ffff8800cba8c5b0 ffff8800cba8c5b8
[  166.674230]  0000000000000000 0000000000000001 ffff8800cf8e33e8 ffff8800cae7f848
[  166.674230] Call Trace:
[  166.674230]  [<ffffffff814b73e8>] list_del+0xd/0x2b
[  166.674230]  [<ffffffff817caeec>] tcf_action_destroy+0x4c/0x71
[  166.674230]  [<ffffffff817ca0ce>] tcf_exts_destroy+0x20/0x2d
[  166.674230]  [<ffffffff817ec2b5>] tcindex_delete+0x196/0x1b7

struct list_head can not be simply copied and we should always init it.

Cc: John Fastabend <[email protected]>
Signed-off-by: Cong Wang <[email protected]>
Acked-by: John Fastabend <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
tom3q pushed a commit that referenced this pull request Oct 7, 2014
This fixes the following crash:

[   63.976822] general protection fault: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
[   63.980094] CPU: 1 PID: 15 Comm: ksoftirqd/1 Not tainted 3.17.0-rc6+ torvalds#648
[   63.980094] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   63.980094] task: ffff880117dea690 ti: ffff880117dfc000 task.ti: ffff880117dfc000
[   63.980094] RIP: 0010:[<ffffffff817e6d07>]  [<ffffffff817e6d07>] u32_destroy_key+0x27/0x6d
[   63.980094] RSP: 0018:ffff880117dffcc0  EFLAGS: 00010202
[   63.980094] RAX: ffff880117dea690 RBX: ffff8800d02e0820 RCX: 0000000000000000
[   63.980094] RDX: 0000000000000001 RSI: 0000000000000002 RDI: 6b6b6b6b6b6b6b6b
[   63.980094] RBP: ffff880117dffcd0 R08: 0000000000000000 R09: 0000000000000000
[   63.980094] R10: 00006c0900006ba8 R11: 00006ba100006b9d R12: 0000000000000001
[   63.980094] R13: ffff8800d02e0898 R14: ffffffff817e6d4d R15: ffff880117387a30
[   63.980094] FS:  0000000000000000(0000) GS:ffff88011a800000(0000) knlGS:0000000000000000
[   63.980094] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[   63.980094] CR2: 00007f07e6732fed CR3: 000000011665b000 CR4: 00000000000006e0
[   63.980094] Stack:
[   63.980094]  ffff88011a9cd300 ffffffff82051ac0 ffff880117dffce0 ffffffff817e6d68
[   63.980094]  ffff880117dffd70 ffffffff810cb4c7 ffffffff810cb3cd ffff880117dfffd8
[   63.980094]  ffff880117dea690 ffff880117dea690 ffff880117dfffd8 000000000000000a
[   63.980094] Call Trace:
[   63.980094]  [<ffffffff817e6d68>] u32_delete_key_freepf_rcu+0x1b/0x1d
[   63.980094]  [<ffffffff810cb4c7>] rcu_process_callbacks+0x3bb/0x691
[   63.980094]  [<ffffffff810cb3cd>] ? rcu_process_callbacks+0x2c1/0x691
[   63.980094]  [<ffffffff817e6d4d>] ? u32_destroy_key+0x6d/0x6d
[   63.980094]  [<ffffffff810780a4>] __do_softirq+0x142/0x323
[   63.980094]  [<ffffffff810782a8>] run_ksoftirqd+0x23/0x53
[   63.980094]  [<ffffffff81092126>] smpboot_thread_fn+0x203/0x221
[   63.980094]  [<ffffffff81091f23>] ? smpboot_unpark_thread+0x33/0x33
[   63.980094]  [<ffffffff8108e44d>] kthread+0xc9/0xd1
[   63.980094]  [<ffffffff819e00ea>] ? do_wait_for_common+0xf8/0x125
[   63.980094]  [<ffffffff8108e384>] ? __kthread_parkme+0x61/0x61
[   63.980094]  [<ffffffff819e43ec>] ret_from_fork+0x7c/0xb0
[   63.980094]  [<ffffffff8108e384>] ? __kthread_parkme+0x61/0x61

tp could be freed in call_rcu callback too, the order is not guaranteed.

John Fastabend says:

====================
Its worth noting why this is safe. Any running schedulers will either
read the valid class field or it will be zeroed.

All schedulers today when the class is 0 do a lookup using the
same call used by the tcf_exts_bind(). So even if we have a running
classifier hit the null class pointer it will do a lookup and get
to the same result. This is particularly fragile at the moment because
the only way to verify this is to audit the schedulers call sites.
====================

Cc: John Fastabend <[email protected]>
Signed-off-by: Cong Wang <[email protected]>
Acked-by: John Fastabend <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
tom3q pushed a commit that referenced this pull request Oct 7, 2014
The L2CAP connection's channel list lock (conn->chan_lock) must never be
taken while already holding a channel lock (chan->lock) in order to
avoid lock-inversion and lockdep warnings. So far the l2cap_chan_connect
function has acquired the chan->lock early in the function and then
later called l2cap_chan_add(conn, chan) which will try to take the
conn->chan_lock. This violates the correct order of taking the locks and
may lead to the following type of lockdep warnings:

-> #1 (&conn->chan_lock){+.+...}:
       [<c109324d>] lock_acquire+0x9d/0x140
       [<c188459c>] mutex_lock_nested+0x6c/0x420
       [<d0aab48e>] l2cap_chan_add+0x1e/0x40 [bluetooth]
       [<d0aac618>] l2cap_chan_connect+0x348/0x8f0 [bluetooth]
       [<d0cc9a91>] lowpan_control_write+0x221/0x2d0 [bluetooth_6lowpan]
-> #0 (&chan->lock){+.+.+.}:
       [<c10928d8>] __lock_acquire+0x1a18/0x1d20
       [<c109324d>] lock_acquire+0x9d/0x140
       [<c188459c>] mutex_lock_nested+0x6c/0x420
       [<d0ab05fd>] l2cap_connect_cfm+0x1dd/0x3f0 [bluetooth]
       [<d0a909c4>] hci_le_meta_evt+0x11a4/0x1260 [bluetooth]
       [<d0a910eb>] hci_event_packet+0x3ab/0x3120 [bluetooth]
       [<d0a7cb08>] hci_rx_work+0x208/0x4a0 [bluetooth]

       CPU0                    CPU1
       ----                    ----
  lock(&conn->chan_lock);
                               lock(&chan->lock);
                               lock(&conn->chan_lock);
  lock(&chan->lock);

Before calling l2cap_chan_add() the channel is not part of the
conn->chan_l list, and can therefore only be accessed by the L2CAP user
(such as l2cap_sock.c). We can therefore assume that it is the
responsibility of the user to handle mutual exclusion until this point
(which we can see is already true in l2cap_sock.c by it in many places
touching chan members without holding chan->lock).

Since the hci_conn and by exctension l2cap_conn creation in the
l2cap_chan_connect() function depend on chan details we cannot simply
add a mutex_lock(&conn->chan_lock) in the beginning of the function
(since the conn object doesn't yet exist there). What we can do however
is move the chan->lock taking later into the function where we already
have the conn object and can that way take conn->chan_lock first.

This patch implements the above strategy and does some other necessary
changes such as using __l2cap_chan_add() which assumes conn->chan_lock
is held, as well as adding a second needed label so the unlocking
happens as it should.

Reported-by: Jukka Rissanen <[email protected]>
Signed-off-by: Johan Hedberg <[email protected]>
Tested-by: Jukka Rissanen <[email protected]>
Acked-by: Jukka Rissanen <[email protected]>
Signed-off-by: Marcel Holtmann <[email protected]>
tom3q pushed a commit that referenced this pull request Oct 7, 2014
This fixes the following OOPS:

   loaded kvm module (v3.17-rc1-168-gcec26bc)
   BUG: unable to handle kernel paging request at fffffffffffffffe
   IP: [<ffffffff81168449>] put_page+0x9/0x30
   PGD 1e15067 PUD 1e17067 PMD 0
   Oops: 0000 [#1] PREEMPT SMP
    [<ffffffffa063271d>] ? kvm_vcpu_reload_apic_access_page+0x5d/0x70 [kvm]
    [<ffffffffa013b6db>] vmx_vcpu_reset+0x21b/0x470 [kvm_intel]
    [<ffffffffa0658816>] ? kvm_pmu_reset+0x76/0xb0 [kvm]
    [<ffffffffa064032a>] kvm_vcpu_reset+0x15a/0x1b0 [kvm]
    [<ffffffffa06403ac>] kvm_arch_vcpu_setup+0x2c/0x50 [kvm]
    [<ffffffffa062e540>] kvm_vm_ioctl+0x200/0x780 [kvm]
    [<ffffffff81212170>] do_vfs_ioctl+0x2d0/0x4b0
    [<ffffffff8108bd99>] ? __mmdrop+0x69/0xb0
    [<ffffffff812123d1>] SyS_ioctl+0x81/0xa0
    [<ffffffff8112a6f6>] ? __audit_syscall_exit+0x1f6/0x2a0
    [<ffffffff817229e9>] system_call_fastpath+0x16/0x1b
   Code: c6 78 ce a3 81 4c 89 e7 e8 d9 80 ff ff 0f 0b 4c 89 e7 e8 8f f6 ff ff e9 fa fe ff ff 66 2e 0f 1f 84 00 00 00 00 00 66 66 66 66 90 <48> f7 07 00 c0 00 00 55 48 89 e5 75 1e 8b 47 1c 85 c0 74 27 f0
   RIP  [<ffffffff81193045>] put_page+0x5/0x50

when not using the in-kernel irqchip ("-machine kernel_irqchip=off"
with QEMU).  The fix is to make the same check in
kvm_vcpu_reload_apic_access_page that we already have
in vmx.c's vm_need_virtualize_apic_accesses().

Reported-by: Jan Kiszka <[email protected]>
Tested-by: Jan Kiszka <[email protected]>
Fixes: 4256f43
Signed-off-by: Paolo Bonzini <[email protected]>
tom3q pushed a commit that referenced this pull request Oct 7, 2014
For commit ocfs2 journal, ocfs2 journal thread will acquire the mutex
osb->journal->j_trans_barrier and wake up jbd2 commit thread, then it
will wait until jbd2 commit thread done. In order journal mode, jbd2
needs flushing dirty data pages first, and this needs get page lock.
So osb->journal->j_trans_barrier should be got before page lock.

But ocfs2_write_zero_page() and ocfs2_write_begin_inline() obey this
locking order, and this will cause deadlock and hung the whole cluster.

One deadlock catched is the following:

PID: 13449  TASK: ffff8802e2f08180  CPU: 31  COMMAND: "oracle"
 #0 [ffff8802ee3f79b0] __schedule at ffffffff8150a524
 #1 [ffff8802ee3f7a58] schedule at ffffffff8150acbf
 #2 [ffff8802ee3f7a68] rwsem_down_failed_common at ffffffff8150cb85
 #3 [ffff8802ee3f7ad8] rwsem_down_read_failed at ffffffff8150cc55
 #4 [ffff8802ee3f7ae8] call_rwsem_down_read_failed at ffffffff812617a4
 #5 [ffff8802ee3f7b50] ocfs2_start_trans at ffffffffa0498919 [ocfs2]
 torvalds#6 [ffff8802ee3f7ba0] ocfs2_zero_start_ordered_transaction at ffffffffa048b2b8 [ocfs2]
 torvalds#7 [ffff8802ee3f7bf0] ocfs2_write_zero_page at ffffffffa048e9bd [ocfs2]
 torvalds#8 [ffff8802ee3f7c80] ocfs2_zero_extend_range at ffffffffa048ec83 [ocfs2]
 torvalds#9 [ffff8802ee3f7ce0] ocfs2_zero_extend at ffffffffa048edfd [ocfs2]
 torvalds#10 [ffff8802ee3f7d50] ocfs2_extend_file at ffffffffa049079e [ocfs2]
 torvalds#11 [ffff8802ee3f7da0] ocfs2_setattr at ffffffffa04910ed [ocfs2]
 torvalds#12 [ffff8802ee3f7e70] notify_change at ffffffff81187d29
 torvalds#13 [ffff8802ee3f7ee0] do_truncate at ffffffff8116bbc1
 torvalds#14 [ffff8802ee3f7f50] sys_ftruncate at ffffffff8116bcbd
 torvalds#15 [ffff8802ee3f7f80] system_call_fastpath at ffffffff81515142
    RIP: 00007f8de750c6f7  RSP: 00007fffe786e478  RFLAGS: 00000206
    RAX: 000000000000004d  RBX: ffffffff81515142  RCX: 0000000000000000
    RDX: 0000000000000200  RSI: 0000000000028400  RDI: 000000000000000d
    RBP: 00007fffe786e040   R8: 0000000000000000   R9: 000000000000000d
    R10: 0000000000000000  R11: 0000000000000206  R12: 000000000000000d
    R13: 00007fffe786e710  R14: 00007f8de70f8340  R15: 0000000000028400
    ORIG_RAX: 000000000000004d  CS: 0033  SS: 002b

crash64> bt
PID: 7610   TASK: ffff88100fd56140  CPU: 1   COMMAND: "ocfs2cmt"
 #0 [ffff88100f4d1c50] __schedule at ffffffff8150a524
 #1 [ffff88100f4d1cf8] schedule at ffffffff8150acbf
 #2 [ffff88100f4d1d08] jbd2_log_wait_commit at ffffffffa01274fd [jbd2]
 #3 [ffff88100f4d1d98] jbd2_journal_flush at ffffffffa01280b4 [jbd2]
 #4 [ffff88100f4d1dd8] ocfs2_commit_cache at ffffffffa0499b14 [ocfs2]
 #5 [ffff88100f4d1e38] ocfs2_commit_thread at ffffffffa0499d38 [ocfs2]
 torvalds#6 [ffff88100f4d1ee8] kthread at ffffffff81090db6
 torvalds#7 [ffff88100f4d1f48] kernel_thread_helper at ffffffff81516284

crash64> bt
PID: 7609   TASK: ffff88100f2d4480  CPU: 0   COMMAND: "jbd2/dm-20-86"
 #0 [ffff88100def3920] __schedule at ffffffff8150a524
 #1 [ffff88100def39c8] schedule at ffffffff8150acbf
 #2 [ffff88100def39d8] io_schedule at ffffffff8150ad6c
 #3 [ffff88100def39f8] sleep_on_page at ffffffff8111069e
 #4 [ffff88100def3a08] __wait_on_bit_lock at ffffffff8150b30a
 #5 [ffff88100def3a58] __lock_page at ffffffff81110687
 torvalds#6 [ffff88100def3ab8] write_cache_pages at ffffffff8111b752
 torvalds#7 [ffff88100def3be8] generic_writepages at ffffffff8111b901
 torvalds#8 [ffff88100def3c48] journal_submit_data_buffers at ffffffffa0120f67 [jbd2]
 torvalds#9 [ffff88100def3cf8] jbd2_journal_commit_transaction at ffffffffa0121372[jbd2]
 torvalds#10 [ffff88100def3e68] kjournald2 at ffffffffa0127a86 [jbd2]
 torvalds#11 [ffff88100def3ee8] kthread at ffffffff81090db6
 torvalds#12 [ffff88100def3f48] kernel_thread_helper at ffffffff81516284

Signed-off-by: Junxiao Bi <[email protected]>
Cc: Mark Fasheh <[email protected]>
Cc: Joel Becker <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
tom3q pushed a commit that referenced this pull request Oct 7, 2014
Fengguang reported following bug and his bisect result points
to this patch ('mm/slab: support slab merge') as root cause.

[    0.466034] BUG: unable to handle kernel paging request at 00010023
[    0.466989] IP: [<c117dcf9>] kernfs_add_one+0x89/0x130
[    0.467812] *pdpt = 0000000000000000 *pde = f000ff53f000ff53
[    0.468000] Oops: 0002 [#1] SMP
[    0.468000] Modules linked in:
[    0.468000] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.17.0-rc6-00089-g36fbfeb #1
[    0.468000] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[    0.468000] task: d303ec90 ti: d3040000 task.ti: d3040000
[    0.468000] EIP: 0060:[<c117dcf9>] EFLAGS: 00010286 CPU: 0
[    0.468000] EIP is at kernfs_add_one+0x89/0x130
[    0.468000] EAX: 542572cb EBX: 00010003 ECX: 00000008 EDX: 2c8de598
[    0.468000] ESI: d311de10 EDI: d311de70 EBP: d3041dd8 ESP: d3041db4
[    0.468000]  DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
[    0.468000] CR0: 8005003b CR2: 00010023 CR3: 01a8a000 CR4: 000006f0
[    0.468000] Stack:
[    0.468000]  d3006f00 00000202 d311de70 d311de10 d3041dd8 c117dba0 d311de10 c159a5c0
[    0.468000]  c1862a00 d3041df0 c117f0f2 00000000 c18629f4 d311de70 00000000 d3041e2c
[    0.468000]  c117f8b5 00001000 00000000 c159a5c0 c18629f4 00000000 00000001 c1862a00
[    0.468000] Call Trace:
[    0.468000]  [<c117dba0>] ? kernfs_new_node+0x30/0x40
[    0.468000]  [<c117f0f2>] __kernfs_create_file+0x92/0xc0
[    0.468000]  [<c117f8b5>] sysfs_add_file_mode_ns+0x95/0x190
[    0.468000]  [<c117f9d7>] sysfs_create_file_ns+0x27/0x40
[    0.468000]  [<c1252ef6>] kobject_add_internal+0x136/0x2c0
[    0.468000]  [<c125e360>] ? kvasprintf+0x40/0x50
[    0.468000]  [<c1252a92>] ? kobject_set_name_vargs+0x42/0x60
[    0.468000]  [<c12530b5>] kobject_init_and_add+0x35/0x50
[    0.468000]  [<c12ad04f>] acpi_sysfs_add_hotplug_profile+0x24/0x4a
[    0.468000]  [<c12a7280>] acpi_scan_add_handler_with_hotplug+0x21/0x28
[    0.468000]  [<c18df524>] acpi_pci_root_init+0x20/0x22
[    0.468000]  [<c18df0e1>] acpi_scan_init+0x24/0x16d
[    0.468000]  [<c18def73>] acpi_init+0x20c/0x224
[    0.468000]  [<c18ded67>] ? acpi_sleep_init+0xab/0xab
[    0.468000]  [<c100041e>] do_one_initcall+0x7e/0x1b0
[    0.468000]  [<c18ded67>] ? acpi_sleep_init+0xab/0xab
[    0.468000]  [<c18b24ba>] ? repair_env_string+0x12/0x54
[    0.468000]  [<c18b24a8>] ? initcall_blacklist+0x7c/0x7c
[    0.468000]  [<c105e100>] ? parse_args+0x160/0x3f0
[    0.468000]  [<c18b2bd1>] kernel_init_freeable+0xfc/0x179
[    0.468000]  [<c156782b>] kernel_init+0xb/0xd0
[    0.468000]  [<c1574601>] ret_from_kernel_thread+0x21/0x30
[    0.468000]  [<c1567820>] ? rest_init+0xb0/0xb0
[snip...]
[    0.468000] EIP: [<c117dcf9>] kernfs_add_one+0x89/0x130 SS:ESP 0068:d3041db4
[    0.468000] CR2: 0000000000010023
[    0.468000] ---[ end trace 4fa173691404b63f ]---
[    0.468000] Kernel panic - not syncing: Fatal exception

This error is caused by wrongly initialized object due to slab merge.
Size of vm_area_struct is 92 bytes in this configuration, and, for better
alignment, this kmem_cache manage memory in 96 bytes unit. But, maybe for
performance reason, if user requests zeroing for this object, object is
cleared up to 92 bytes.

Meanwhile, size of kernfs_node_cache is 96 bytes so that it can be merged
with kmem_cache for vm_area_struct. In this situation, if user request
zeroing for objects for kernfs_node_cache, object is only cleared up to
92 bytes. So, kernfs_node had odd value on iattr field and this results in
de-referencing wrong address bug.

To fix this problem, object size is adjusted when merging occurs.
After this change, zeroing will be done to complete object so that
de-referencing wrong address can't happen.

Reported-by: Fengguang Wu <[email protected]>
Signed-off-by: Joonsoo Kim <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
tom3q pushed a commit that referenced this pull request Oct 7, 2014
cat /sys/.../pools followed by removal the device leads to:

|======================================================
|[ INFO: possible circular locking dependency detected ]
|3.17.0-rc4+ #1498 Not tainted
|-------------------------------------------------------
|rmmod/2505 is trying to acquire lock:
| (s_active#28){++++.+}, at: [<c017f754>] kernfs_remove_by_name_ns+0x3c/0x88
|
|but task is already holding lock:
| (pools_lock){+.+.+.}, at: [<c011494c>] dma_pool_destroy+0x18/0x17c
|
|which lock already depends on the new lock.
|the existing dependency chain (in reverse order) is:
|
|-> #1 (pools_lock){+.+.+.}:
|   [<c0114ae8>] show_pools+0x30/0xf8
|   [<c0313210>] dev_attr_show+0x1c/0x48
|   [<c0180e84>] sysfs_kf_seq_show+0x88/0x10c
|   [<c017f960>] kernfs_seq_show+0x24/0x28
|   [<c013efc4>] seq_read+0x1b8/0x480
|   [<c011e820>] vfs_read+0x8c/0x148
|   [<c011ea10>] SyS_read+0x40/0x8c
|   [<c000e960>] ret_fast_syscall+0x0/0x48
|
|-> #0 (s_active#28){++++.+}:
|   [<c017e9ac>] __kernfs_remove+0x258/0x2ec
|   [<c017f754>] kernfs_remove_by_name_ns+0x3c/0x88
|   [<c0114a7c>] dma_pool_destroy+0x148/0x17c
|   [<c03ad288>] hcd_buffer_destroy+0x20/0x34
|   [<c03a4780>] usb_remove_hcd+0x110/0x1a4

The problem is the lock order of pools_lock and kernfs_mutex in
dma_pool_destroy() vs show_pools() call path.

This patch breaks out the creation of the sysfs file outside of the
pools_lock mutex.  The newly added pools_reg_lock ensures that there is no
race of create vs destroy code path in terms whether or not the sysfs file
has to be deleted (and was it deleted before we try to create a new one)
and what to do if device_create_file() failed.

Signed-off-by: Sebastian Andrzej Siewior <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
tom3q pushed a commit that referenced this pull request Oct 7, 2014
…_map_entry

By the following commits, we prevented from allocating firmware_map_entry
of same memory range:
  f0093ed: drivers/firmware/memmap.c: don't allocate firmware_map_entry
            of same memory range
  49c8b24: drivers/firmware/memmap.c: pass the correct argument to
            firmware_map_find_entry_bootmem()

But it's not enough. When PNP0C80 device is added by acpi_scan_init(),
memmap sysfses of same firmware_map_entry are created twice as follows:

  # cat /sys/firmware/memmap/*/start
  0x40000000000
  0x60000000000
  0x4a837000
  0x4a83a000
  0x4a8b5000
  ...
  0x40000000000
  0x60000000000
  ...

The flows of the issues are as follows:

  1. e820_reserve_resources() allocates firmware_map_entrys of all
     memory ranges defined in e820. And, these firmware_map_entrys
     are linked with map_entries list.

     map_entries -> entry 1 -> ... -> entry N

  2. When PNP0C80 device is limited by mem= boot option, acpi_scan_init()
     added the memory device. In this case, firmware_map_add_hotplug()
     allocates firmware_map_entry and creates memmap sysfs.

     map_entries -> entry 1 -> ... -> entry N -> entry N+1
                                                 |
                                                 memmap 1

  3. firmware_memmap_init() creates memmap sysfses of firmware_map_entrys
     linked with map_entries.

     map_entries -> entry 1 -> ... -> entry N -> entry N+1
                     |                 |             |
                     memmap 2          memmap N+1    memmap 1
                                                     memmap N+2

So while hot removing the PNP0C80 device, kernel panic occurs as follows:

     BUG: unable to handle kernel paging request at 00000001003e000b
      IP: sysfs_open_file+0x46/0x2b0
      PGD 203a89fe067 PUD 0
      Oops: 0000 [#1] SMP
      ...
      Call Trace:
        do_dentry_open+0x1ef/0x2a0
        finish_open+0x31/0x40
        do_last+0x57c/0x1220
        path_openat+0xc2/0x4c0
        do_filp_open+0x4b/0xb0
        do_sys_open+0xf3/0x1f0
        SyS_open+0x1e/0x20
        system_call_fastpath+0x16/0x1b

The patch adds a check of confirming whether memmap sysfs of
firmware_map_entry has been created, and does not create memmap
sysfs of same firmware_map_entry.

Signed-off-by: Yasuaki Ishimatsu <[email protected]>
Cc: Santosh Shilimkar <[email protected]>
Cc: Toshi Kani <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
tom3q pushed a commit that referenced this pull request Oct 7, 2014
…heck

If the type we receive is greater than ST_MAX_CHANNELS we can't rely on
type as vector index since we would be accessing unknown memory when we use the type
as index.

 Unable to handle kernel NULL pointer dereference at virtual address 0000001b
 pgd = c0004000
 [0000001b] *pgd=00000000
 Internal error: Oops: 17 [#1] PREEMPT SMP ARM
 Modules linked in: btwilink wl12xx wlcore mac80211 cfg80211 rfcomm bnep bluo
 CPU: 0    Tainted: G        W     (3.4.0+ torvalds#15)
 PC is at st_int_recv+0x278/0x344
 LR is at get_parent_ip+0x14/0x30
 pc : [<c03b01a8>]    lr : [<c007273c>]    psr: 200f0193
 sp : dc631ed0  ip : e3e21c24  fp : dc631f04
 r10: 00000000  r9 : 600f0113  r8 : 0000003f
 r7 : e3e21b14  r6 : 00000067  r5 : e2e49c1c  r4 : e3e21a80
 r3 : 00000001  r2 : 00000001  r1 : 00000001  r0 : 600f0113
 Flags: nzCv  IRQs off  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
 Control: 10c5387d  Table: 9c50004a  DAC: 00000015

Signed-off-by: Gustavo Padovan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
tom3q pushed a commit that referenced this pull request Oct 7, 2014
…ster_one_node

Commit 92d585e ("numa: fix NULL pointer access and memory
leak in unregister_one_node()") added kfree() of node struct in
unregister_one_node(). But node struct is freed by node_device_release()
which is called in  unregister_node(). So by adding the kfree(),
node struct is freed two times.

While hot removing memory, the commit leads the following BUG_ON():

  kernel BUG at mm/slub.c:3346!
  invalid opcode: 0000 [#1] SMP
  [...]
  Call Trace:
   [...] unregister_one_node
   [...] try_offline_node
   [...] remove_memory
   [...] acpi_memory_device_remove
   [...] acpi_bus_trim
   [...] acpi_bus_trim
   [...] acpi_device_hotplug
   [...] acpi_hotplug_work_fn
   [...] process_one_work
   [...] worker_thread
   [...] ? rescuer_thread
   [...] kthread
   [...] ? kthread_create_on_node
   [...] ret_from_fork
   [...] ? kthread_create_on_node

This patch removes unnecessary kfree() from unregister_one_node().

Signed-off-by: Yasuaki Ishimatsu <[email protected]>
Cc: Xishi Qiu <[email protected]>
Cc: [email protected] # v3.16+
Fixes: 92d585e "numa: fix NULL pointer access and memory leak in unregister_one_node()"
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
tom3q pushed a commit that referenced this pull request Oct 7, 2014
Christopher Head 2014-06-28 05:26:20 UTC described:
"I tried to reproduce this on 3.12.21. Instead, when I do "echo hello > foo"
in an ecryptfs mount with ecryptfs_xattr specified, I get a kernel crash:

BUG: unable to handle kernel NULL pointer dereference at           (null)
IP: [<ffffffff8110eb39>] fsstack_copy_attr_all+0x2/0x61
PGD d7840067 PUD b2c3c067 PMD 0
Oops: 0002 [#1] SMP
Modules linked in: nvidia(PO)
CPU: 3 PID: 3566 Comm: bash Tainted: P           O 3.12.21-gentoo-r1 #2
Hardware name: ASUSTek Computer Inc. G60JX/G60JX, BIOS 206 03/15/2010
task: ffff8801948944c0 ti: ffff8800bad70000 task.ti: ffff8800bad70000
RIP: 0010:[<ffffffff8110eb39>]  [<ffffffff8110eb39>] fsstack_copy_attr_all+0x2/0x61
RSP: 0018:ffff8800bad71c10  EFLAGS: 00010246
RAX: 00000000000181a4 RBX: ffff880198648480 RCX: 0000000000000000
RDX: 0000000000000004 RSI: ffff880172010450 RDI: 0000000000000000
RBP: ffff880198490e40 R08: 0000000000000000 R09: 0000000000000000
R10: ffff880172010450 R11: ffffea0002c51e80 R12: 0000000000002000
R13: 000000000000001a R14: 0000000000000000 R15: ffff880198490e40
FS:  00007ff224caa700(0000) GS:ffff88019fcc0000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000000bb07f000 CR4: 00000000000007e0
Stack:
ffffffff811826e8 ffff8800a39d8000 0000000000000000 000000000000001a
ffff8800a01d0000 ffff8800a39d8000 ffffffff81185fd5 ffffffff81082c2c
00000001a39d8000 53d0abbc98490e40 0000000000000037 ffff8800a39d8220
Call Trace:
[<ffffffff811826e8>] ? ecryptfs_setxattr+0x40/0x52
[<ffffffff81185fd5>] ? ecryptfs_write_metadata+0x1b3/0x223
[<ffffffff81082c2c>] ? should_resched+0x5/0x23
[<ffffffff8118322b>] ? ecryptfs_initialize_file+0xaf/0xd4
[<ffffffff81183344>] ? ecryptfs_create+0xf4/0x142
[<ffffffff810f8c0d>] ? vfs_create+0x48/0x71
[<ffffffff810f9c86>] ? do_last.isra.68+0x559/0x952
[<ffffffff810f7ce7>] ? link_path_walk+0xbd/0x458
[<ffffffff810fa2a3>] ? path_openat+0x224/0x472
[<ffffffff810fa7bd>] ? do_filp_open+0x2b/0x6f
[<ffffffff81103606>] ? __alloc_fd+0xd6/0xe7
[<ffffffff810ee6ab>] ? do_sys_open+0x65/0xe9
[<ffffffff8157d022>] ? system_call_fastpath+0x16/0x1b
RIP  [<ffffffff8110eb39>] fsstack_copy_attr_all+0x2/0x61
RSP <ffff8800bad71c10>
CR2: 0000000000000000
---[ end trace df9dba5f1ddb8565 ]---"

If we create a file when we mount with ecryptfs_xattr_metadata option, we will
encounter a crash in this path:
->ecryptfs_create
  ->ecryptfs_initialize_file
    ->ecryptfs_write_metadata
      ->ecryptfs_write_metadata_to_xattr
        ->ecryptfs_setxattr
          ->fsstack_copy_attr_all
It's because our dentry->d_inode used in fsstack_copy_attr_all is NULL, and it
will be initialized when ecryptfs_initialize_file finish.

So we should skip copying attr from lower inode when the value of ->d_inode is
invalid.

Signed-off-by: Chao Yu <[email protected]>
Cc: [email protected] # v3.2+: b59db43 eCryptfs: Prevent file create race condition
Signed-off-by: Tyler Hicks <[email protected]>
tom3q pushed a commit that referenced this pull request Oct 26, 2014
If hexlen is odd then function returns an error.
Use IS_ERR to check for error, otherwise invalid pointer
is used and kernel gives oops:

[  132.816522] BUG: unable to handle kernel paging request at
ffffffffffffffea
[  132.819902] IP: [<ffffffff812bfc20>] asymmetric_key_id_same+0x14/0x36
[  132.820302] PGD 1a12067 PUD 1a14067 PMD 0
[  132.820302] Oops: 0000 [#1] SMP
[  132.820302] Modules linked in: bridge(E) stp(E) llc(E) evdev(E)
serio_raw(E) i2c_piix4(E) button(E) fuse(E)
[  132.820302] CPU: 0 PID: 2993 Comm: cat Tainted: G            E
3.16.0-kds+ #2847
[  132.820302] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[  132.820302] task: ffff88004249a430 ti: ffff880056640000 task.ti:
ffff880056640000
[  132.820302] RIP: 0010:[<ffffffff812bfc20>]  [<ffffffff812bfc20>]
asymmetric_key_id_same+0x14/0x36
[  132.820302] RSP: 0018:ffff880056643930  EFLAGS: 00010246
[  132.820302] RAX: 0000000000000000 RBX: ffffffffffffffea RCX:
ffff880056643ae0
[  132.820302] RDX: 000000000000005e RSI: ffffffffffffffea RDI:
ffff88005bac9300
[  132.820302] RBP: ffff880056643948 R08: 0000000000000003 R09:
00000007504aa01a
[  132.820302] R10: 0000000000000000 R11: 0000000000000000 R12:
ffff88005d68ca40
[  132.820302] R13: 0000000000000101 R14: 0000000000000000 R15:
ffff88005bac5280
[  132.820302] FS:  00007f67a153c740(0000) GS:ffff88005da00000(0000)
knlGS:0000000000000000
[  132.820302] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[  132.820302] CR2: ffffffffffffffea CR3: 000000002e663000 CR4:
00000000000006f0
[  132.820302] Stack:
[  132.820302]  ffffffff812bfc66 ffff880056643ae0 ffff88005bac5280
ffff880056643958
[  132.820302]  ffffffff812bfc9d ffff880056643980 ffffffff812971d9
ffff88005ce930c1
[  132.820302]  ffff88005ce930c0 0000000000000000 ffff8800566439c8
ffffffff812fb753
[  132.820302] Call Trace:
[  132.820302]  [<ffffffff812bfc66>] ? asymmetric_match_key_ids+0x24/0x42
[  132.820302]  [<ffffffff812bfc9d>] asymmetric_key_cmp+0x19/0x1b
[  132.820302]  [<ffffffff812971d9>] keyring_search_iterator+0x74/0xd7
[  132.820302]  [<ffffffff812fb753>] assoc_array_subtree_iterate+0x67/0xd2
[  132.820302]  [<ffffffff81297165>] ? key_default_cmp+0x20/0x20
[  132.820302]  [<ffffffff812fbaa1>] assoc_array_iterate+0x19/0x1e
[  132.820302]  [<ffffffff81297332>] search_nested_keyrings+0xf6/0x2b6
[  132.820302]  [<ffffffff810728da>] ? sched_clock_cpu+0x91/0xa2
[  132.820302]  [<ffffffff810860d2>] ? mark_held_locks+0x58/0x6e
[  132.820302]  [<ffffffff810a137d>] ? current_kernel_time+0x77/0xb8
[  132.820302]  [<ffffffff81297871>] keyring_search_aux+0xe1/0x14c
[  132.820302]  [<ffffffff812977fc>] ? keyring_search_aux+0x6c/0x14c
[  132.820302]  [<ffffffff8129796b>] keyring_search+0x8f/0xb6
[  132.820302]  [<ffffffff812bfc84>] ? asymmetric_match_key_ids+0x42/0x42
[  132.820302]  [<ffffffff81297165>] ? key_default_cmp+0x20/0x20
[  132.820302]  [<ffffffff812ab9e3>] asymmetric_verify+0xa4/0x214
[  132.820302]  [<ffffffff812ab90e>] integrity_digsig_verify+0xb1/0xe2
[  132.820302]  [<ffffffff812abe41>] ? evm_verifyxattr+0x6a/0x7a
[  132.820302]  [<ffffffff812b0390>] ima_appraise_measurement+0x160/0x370
[  132.820302]  [<ffffffff81161db2>] ? d_absolute_path+0x5b/0x7a
[  132.820302]  [<ffffffff812ada30>] process_measurement+0x322/0x404

Reported-by: Dmitry Kasatkin <[email protected]>
Signed-off-by: Dmitry Kasatkin <[email protected]>
Signed-off-by: David Howells <[email protected]>
tom3q pushed a commit that referenced this pull request Oct 26, 2014
For commit ocfs2 journal, ocfs2 journal thread will acquire the mutex
osb->journal->j_trans_barrier and wake up jbd2 commit thread, then it
will wait until jbd2 commit thread done. In order journal mode, jbd2
needs flushing dirty data pages first, and this needs get page lock.
So osb->journal->j_trans_barrier should be got before page lock.

But ocfs2_write_zero_page() and ocfs2_write_begin_inline() obey this
locking order, and this will cause deadlock and hung the whole cluster.

One deadlock catched is the following:

PID: 13449  TASK: ffff8802e2f08180  CPU: 31  COMMAND: "oracle"
 #0 [ffff8802ee3f79b0] __schedule at ffffffff8150a524
 #1 [ffff8802ee3f7a58] schedule at ffffffff8150acbf
 #2 [ffff8802ee3f7a68] rwsem_down_failed_common at ffffffff8150cb85
 #3 [ffff8802ee3f7ad8] rwsem_down_read_failed at ffffffff8150cc55
 #4 [ffff8802ee3f7ae8] call_rwsem_down_read_failed at ffffffff812617a4
 #5 [ffff8802ee3f7b50] ocfs2_start_trans at ffffffffa0498919 [ocfs2]
 torvalds#6 [ffff8802ee3f7ba0] ocfs2_zero_start_ordered_transaction at ffffffffa048b2b8 [ocfs2]
 torvalds#7 [ffff8802ee3f7bf0] ocfs2_write_zero_page at ffffffffa048e9bd [ocfs2]
 torvalds#8 [ffff8802ee3f7c80] ocfs2_zero_extend_range at ffffffffa048ec83 [ocfs2]
 torvalds#9 [ffff8802ee3f7ce0] ocfs2_zero_extend at ffffffffa048edfd [ocfs2]
 torvalds#10 [ffff8802ee3f7d50] ocfs2_extend_file at ffffffffa049079e [ocfs2]
 torvalds#11 [ffff8802ee3f7da0] ocfs2_setattr at ffffffffa04910ed [ocfs2]
 torvalds#12 [ffff8802ee3f7e70] notify_change at ffffffff81187d29
 torvalds#13 [ffff8802ee3f7ee0] do_truncate at ffffffff8116bbc1
 torvalds#14 [ffff8802ee3f7f50] sys_ftruncate at ffffffff8116bcbd
 torvalds#15 [ffff8802ee3f7f80] system_call_fastpath at ffffffff81515142
    RIP: 00007f8de750c6f7  RSP: 00007fffe786e478  RFLAGS: 00000206
    RAX: 000000000000004d  RBX: ffffffff81515142  RCX: 0000000000000000
    RDX: 0000000000000200  RSI: 0000000000028400  RDI: 000000000000000d
    RBP: 00007fffe786e040   R8: 0000000000000000   R9: 000000000000000d
    R10: 0000000000000000  R11: 0000000000000206  R12: 000000000000000d
    R13: 00007fffe786e710  R14: 00007f8de70f8340  R15: 0000000000028400
    ORIG_RAX: 000000000000004d  CS: 0033  SS: 002b

crash64> bt
PID: 7610   TASK: ffff88100fd56140  CPU: 1   COMMAND: "ocfs2cmt"
 #0 [ffff88100f4d1c50] __schedule at ffffffff8150a524
 #1 [ffff88100f4d1cf8] schedule at ffffffff8150acbf
 #2 [ffff88100f4d1d08] jbd2_log_wait_commit at ffffffffa01274fd [jbd2]
 #3 [ffff88100f4d1d98] jbd2_journal_flush at ffffffffa01280b4 [jbd2]
 #4 [ffff88100f4d1dd8] ocfs2_commit_cache at ffffffffa0499b14 [ocfs2]
 #5 [ffff88100f4d1e38] ocfs2_commit_thread at ffffffffa0499d38 [ocfs2]
 torvalds#6 [ffff88100f4d1ee8] kthread at ffffffff81090db6
 torvalds#7 [ffff88100f4d1f48] kernel_thread_helper at ffffffff81516284

crash64> bt
PID: 7609   TASK: ffff88100f2d4480  CPU: 0   COMMAND: "jbd2/dm-20-86"
 #0 [ffff88100def3920] __schedule at ffffffff8150a524
 #1 [ffff88100def39c8] schedule at ffffffff8150acbf
 #2 [ffff88100def39d8] io_schedule at ffffffff8150ad6c
 #3 [ffff88100def39f8] sleep_on_page at ffffffff8111069e
 #4 [ffff88100def3a08] __wait_on_bit_lock at ffffffff8150b30a
 #5 [ffff88100def3a58] __lock_page at ffffffff81110687
 torvalds#6 [ffff88100def3ab8] write_cache_pages at ffffffff8111b752
 torvalds#7 [ffff88100def3be8] generic_writepages at ffffffff8111b901
 torvalds#8 [ffff88100def3c48] journal_submit_data_buffers at ffffffffa0120f67 [jbd2]
 torvalds#9 [ffff88100def3cf8] jbd2_journal_commit_transaction at ffffffffa0121372[jbd2]
 torvalds#10 [ffff88100def3e68] kjournald2 at ffffffffa0127a86 [jbd2]
 torvalds#11 [ffff88100def3ee8] kthread at ffffffff81090db6
 torvalds#12 [ffff88100def3f48] kernel_thread_helper at ffffffff81516284

Signed-off-by: Junxiao Bi <[email protected]>
Cc: Mark Fasheh <[email protected]>
Cc: Joel Becker <[email protected]>
Cc: Alex Chen <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
tom3q pushed a commit that referenced this pull request Oct 26, 2014
cat /sys/.../pools followed by removal the device leads to:

|======================================================
|[ INFO: possible circular locking dependency detected ]
|3.17.0-rc4+ #1498 Not tainted
|-------------------------------------------------------
|rmmod/2505 is trying to acquire lock:
| (s_active#28){++++.+}, at: [<c017f754>] kernfs_remove_by_name_ns+0x3c/0x88
|
|but task is already holding lock:
| (pools_lock){+.+.+.}, at: [<c011494c>] dma_pool_destroy+0x18/0x17c
|
|which lock already depends on the new lock.
|the existing dependency chain (in reverse order) is:
|
|-> #1 (pools_lock){+.+.+.}:
|   [<c0114ae8>] show_pools+0x30/0xf8
|   [<c0313210>] dev_attr_show+0x1c/0x48
|   [<c0180e84>] sysfs_kf_seq_show+0x88/0x10c
|   [<c017f960>] kernfs_seq_show+0x24/0x28
|   [<c013efc4>] seq_read+0x1b8/0x480
|   [<c011e820>] vfs_read+0x8c/0x148
|   [<c011ea10>] SyS_read+0x40/0x8c
|   [<c000e960>] ret_fast_syscall+0x0/0x48
|
|-> #0 (s_active#28){++++.+}:
|   [<c017e9ac>] __kernfs_remove+0x258/0x2ec
|   [<c017f754>] kernfs_remove_by_name_ns+0x3c/0x88
|   [<c0114a7c>] dma_pool_destroy+0x148/0x17c
|   [<c03ad288>] hcd_buffer_destroy+0x20/0x34
|   [<c03a4780>] usb_remove_hcd+0x110/0x1a4

The problem is the lock order of pools_lock and kernfs_mutex in
dma_pool_destroy() vs show_pools() call path.

This patch breaks out the creation of the sysfs file outside of the
pools_lock mutex.  The newly added pools_reg_lock ensures that there is no
race of create vs destroy code path in terms whether or not the sysfs file
has to be deleted (and was it deleted before we try to create a new one)
and what to do if device_create_file() failed.

Signed-off-by: Sebastian Andrzej Siewior <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
tom3q pushed a commit that referenced this pull request Oct 26, 2014
…_map_entry

By the following commits, we prevented from allocating firmware_map_entry
of same memory range:
  f0093ed: drivers/firmware/memmap.c: don't allocate firmware_map_entry
            of same memory range
  49c8b24: drivers/firmware/memmap.c: pass the correct argument to
            firmware_map_find_entry_bootmem()

But it's not enough. When PNP0C80 device is added by acpi_scan_init(),
memmap sysfses of same firmware_map_entry are created twice as follows:

  # cat /sys/firmware/memmap/*/start
  0x40000000000
  0x60000000000
  0x4a837000
  0x4a83a000
  0x4a8b5000
  ...
  0x40000000000
  0x60000000000
  ...

The flows of the issues are as follows:

  1. e820_reserve_resources() allocates firmware_map_entrys of all
     memory ranges defined in e820. And, these firmware_map_entrys
     are linked with map_entries list.

     map_entries -> entry 1 -> ... -> entry N

  2. When PNP0C80 device is limited by mem= boot option, acpi_scan_init()
     added the memory device. In this case, firmware_map_add_hotplug()
     allocates firmware_map_entry and creates memmap sysfs.

     map_entries -> entry 1 -> ... -> entry N -> entry N+1
                                                 |
                                                 memmap 1

  3. firmware_memmap_init() creates memmap sysfses of firmware_map_entrys
     linked with map_entries.

     map_entries -> entry 1 -> ... -> entry N -> entry N+1
                     |                 |             |
                     memmap 2          memmap N+1    memmap 1
                                                     memmap N+2

So while hot removing the PNP0C80 device, kernel panic occurs as follows:

     BUG: unable to handle kernel paging request at 00000001003e000b
      IP: sysfs_open_file+0x46/0x2b0
      PGD 203a89fe067 PUD 0
      Oops: 0000 [#1] SMP
      ...
      Call Trace:
        do_dentry_open+0x1ef/0x2a0
        finish_open+0x31/0x40
        do_last+0x57c/0x1220
        path_openat+0xc2/0x4c0
        do_filp_open+0x4b/0xb0
        do_sys_open+0xf3/0x1f0
        SyS_open+0x1e/0x20
        system_call_fastpath+0x16/0x1b

The patch adds a check of confirming whether memmap sysfs of
firmware_map_entry has been created, and does not create memmap
sysfs of same firmware_map_entry.

Signed-off-by: Yasuaki Ishimatsu <[email protected]>
Cc: Santosh Shilimkar <[email protected]>
Cc: Toshi Kani <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
tom3q pushed a commit that referenced this pull request Oct 26, 2014
…ap()

Error report likely result in IO so it is bad idea to do it from
atomic context.

This patch should fix following issue:

BUG: sleeping function called from invalid context at include/linux/buffer_head.h:349
in_atomic(): 1, irqs_disabled(): 0, pid: 137, name: kworker/u128:1
5 locks held by kworker/u128:1/137:
 #0:  ("writeback"){......}, at: [<ffffffff81085618>] process_one_work+0x228/0x4d0
 #1:  ((&(&wb->dwork)->work)){......}, at: [<ffffffff81085618>] process_one_work+0x228/0x4d0
 #2:  (jbd2_handle){......}, at: [<ffffffff81242622>] start_this_handle+0x712/0x7b0
 #3:  (&ei->i_data_sem){......}, at: [<ffffffff811fa387>] ext4_map_blocks+0x297/0x430
 #4:  (&(&bgl->locks[i].lock)->rlock){......}, at: [<ffffffff811f3180>] ext4_read_block_bitmap_nowait+0x5d0/0x630
CPU: 3 PID: 137 Comm: kworker/u128:1 Not tainted 3.17.0-rc2-00184-g82752e4 torvalds#165
Hardware name: Intel Corporation W2600CR/W2600CR, BIOS SE5C600.86B.99.99.x028.061320111235 06/13/2011
Workqueue: writeback bdi_writeback_workfn (flush-1:0)
 0000000000000411 ffff880813777288 ffffffff815c7fdc ffff880813777288
 ffff880813a8bba0 ffff8808137772a8 ffffffff8108fb30 ffff880803e01e38
 ffff880803e01e38 ffff8808137772c8 ffffffff811a8d53 ffff88080ecc6000
Call Trace:
 [<ffffffff815c7fdc>] dump_stack+0x51/0x6d
 [<ffffffff8108fb30>] __might_sleep+0xf0/0x100
 [<ffffffff811a8d53>] __sync_dirty_buffer+0x43/0xe0
 [<ffffffff811a8e03>] sync_dirty_buffer+0x13/0x20
 [<ffffffff8120f581>] ext4_commit_super+0x1d1/0x230
 [<ffffffff8120fa03>] save_error_info+0x23/0x30
 [<ffffffff8120fd06>] __ext4_error+0xb6/0xd0
 [<ffffffff8120f260>] ? ext4_group_desc_csum+0x140/0x190
 [<ffffffff811f2d8c>] ext4_read_block_bitmap_nowait+0x1dc/0x630
 [<ffffffff8122e23a>] ext4_mb_init_cache+0x21a/0x8f0
 [<ffffffff8113ae95>] ? lru_cache_add+0x55/0x60
 [<ffffffff8112e16c>] ? add_to_page_cache_lru+0x6c/0x80
 [<ffffffff8122eaa0>] ext4_mb_init_group+0x190/0x280
 [<ffffffff8122ec51>] ext4_mb_good_group+0xc1/0x190
 [<ffffffff8123309a>] ext4_mb_regular_allocator+0x17a/0x410
 [<ffffffff8122c821>] ? ext4_mb_use_preallocated+0x31/0x380
 [<ffffffff81233535>] ? ext4_mb_new_blocks+0x205/0x8e0
 [<ffffffff8116ed5c>] ? kmem_cache_alloc+0xfc/0x180
 [<ffffffff812335b0>] ext4_mb_new_blocks+0x280/0x8e0
 [<ffffffff8116f2c4>] ? __kmalloc+0x144/0x1c0
 [<ffffffff81221797>] ? ext4_find_extent+0x97/0x320
 [<ffffffff812257f4>] ext4_ext_map_blocks+0xbc4/0x1050
 [<ffffffff811fa387>] ? ext4_map_blocks+0x297/0x430
 [<ffffffff811fa3ab>] ext4_map_blocks+0x2bb/0x430
 [<ffffffff81200e43>] ? ext4_init_io_end+0x23/0x50
 [<ffffffff811feb44>] ext4_writepages+0x564/0xaf0
 [<ffffffff815cde3b>] ? _raw_spin_unlock+0x2b/0x40
 [<ffffffff810ac7bd>] ? lock_release_non_nested+0x2fd/0x3c0
 [<ffffffff811a009e>] ? writeback_sb_inodes+0x10e/0x490
 [<ffffffff811a009e>] ? writeback_sb_inodes+0x10e/0x490
 [<ffffffff811377e3>] do_writepages+0x23/0x40
 [<ffffffff8119c8ce>] __writeback_single_inode+0x9e/0x280
 [<ffffffff811a026b>] writeback_sb_inodes+0x2db/0x490
 [<ffffffff811a0664>] wb_writeback+0x174/0x2d0
 [<ffffffff810ac359>] ? lock_release_holdtime+0x29/0x190
 [<ffffffff811a0863>] wb_do_writeback+0xa3/0x200
 [<ffffffff811a0a40>] bdi_writeback_workfn+0x80/0x230
 [<ffffffff81085618>] ? process_one_work+0x228/0x4d0
 [<ffffffff810856cd>] process_one_work+0x2dd/0x4d0
 [<ffffffff81085618>] ? process_one_work+0x228/0x4d0
 [<ffffffff81085c1d>] worker_thread+0x35d/0x460
 [<ffffffff810858c0>] ? process_one_work+0x4d0/0x4d0
 [<ffffffff810858c0>] ? process_one_work+0x4d0/0x4d0
 [<ffffffff8108a885>] kthread+0xf5/0x100
 [<ffffffff810990e5>] ? local_clock+0x25/0x30
 [<ffffffff8108a790>] ? __init_kthread_worker+0x70/0x70
 [<ffffffff815ce2ac>] ret_from_fork+0x7c/0xb0
 [<ffffffff8108a790>] ? __init_kthread_work

Signed-off-by: Dmitry Monakhov <[email protected]>
Signed-off-by: Theodore Ts'o <[email protected]>
tom3q pushed a commit that referenced this pull request Oct 26, 2014
…rder detected

remove spinlock in cpdma_desc_pool_destroy() as there is no active cpdma
channel and iounmap should be called without auquiring lock.

root@dra7xx-evm:~# modprobe -r ti_cpsw
[   50.539743]
[   50.541312] ======================================================
[   50.547796] [ INFO: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected ]
[   50.554826] 3.14.19-02124-g95c5b7b torvalds#308 Not tainted
[   50.559939] ------------------------------------------------------
[   50.566416] modprobe/1921 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire:
[   50.573347]  (vmap_area_lock){+.+...}, at: [<c01127fc>] find_vmap_area+0x10/0x6c
[   50.581132]
[   50.581132] and this task is already holding:
[   50.587249]  (&(&pool->lock)->rlock#2){..-...}, at: [<bf017c74>] cpdma_ctlr_destroy+0x5c/0x114 [davinci_cpdma]
[   50.597766] which would create a new lock dependency:
[   50.603048]  (&(&pool->lock)->rlock#2){..-...} -> (vmap_area_lock){+.+...}
[   50.610296]
[   50.610296] but this new dependency connects a SOFTIRQ-irq-safe lock:
[   50.618601]  (&(&pool->lock)->rlock#2){..-...}
... which became SOFTIRQ-irq-safe at:
[   50.626829]   [<c06585a4>] _raw_spin_lock_irqsave+0x38/0x4c
[   50.632677]   [<bf01773c>] cpdma_desc_free.constprop.7+0x28/0x58 [davinci_cpdma]
[   50.640437]   [<bf0177e8>] __cpdma_chan_free+0x7c/0xa8 [davinci_cpdma]
[   50.647289]   [<bf017908>] __cpdma_chan_process+0xf4/0x134 [davinci_cpdma]
[   50.654512]   [<bf017984>] cpdma_chan_process+0x3c/0x54 [davinci_cpdma]
[   50.661455]   [<bf0277e8>] cpsw_poll+0x14/0xa8 [ti_cpsw]
[   50.667038]   [<c05844f4>] net_rx_action+0xc0/0x1e8
[   50.672150]   [<c0048234>] __do_softirq+0xcc/0x304
[   50.677183]   [<c004873c>] irq_exit+0xa8/0xfc
[   50.681751]   [<c000eeac>] handle_IRQ+0x50/0xb0
[   50.686513]   [<c0008638>] gic_handle_irq+0x28/0x5c
[   50.691628]   [<c06590a4>] __irq_svc+0x44/0x5c
[   50.696289]   [<c0658ab4>] _raw_spin_unlock_irqrestore+0x34/0x44
[   50.702591]   [<c065a9c4>] do_page_fault.part.9+0x144/0x3c4
[   50.708433]   [<c065acb8>] do_page_fault+0x74/0x84
[   50.713453]   [<c00083dc>] do_DataAbort+0x34/0x98
[   50.718391]   [<c065923c>] __dabt_usr+0x3c/0x40
[   50.723148]
[   50.723148] to a SOFTIRQ-irq-unsafe lock:
[   50.728893]  (vmap_area_lock){+.+...}
... which became SOFTIRQ-irq-unsafe at:
[   50.736476] ...  [<c06584e8>] _raw_spin_lock+0x28/0x38
[   50.741876]   [<c011376c>] alloc_vmap_area.isra.28+0xb8/0x300
[   50.747908]   [<c0113a44>] __get_vm_area_node.isra.29+0x90/0x134
[   50.754210]   [<c011486c>] get_vm_area_caller+0x3c/0x48
[   50.759692]   [<c0114be0>] vmap+0x40/0x78
[   50.763900]   [<c09442f0>] check_writebuffer_bugs+0x54/0x1a0
[   50.769835]   [<c093eac0>] start_kernel+0x320/0x388
[   50.774952]   [<80008074>] 0x80008074
[   50.778793]
[   50.778793] other info that might help us debug this:
[   50.778793]
[   50.787181]  Possible interrupt unsafe locking scenario:
[   50.787181]
[   50.794295]        CPU0                    CPU1
[   50.799042]        ----                    ----
[   50.803785]   lock(vmap_area_lock);
[   50.807446]                                local_irq_disable();
[   50.813652]                                lock(&(&pool->lock)->rlock#2);
[   50.820782]                                lock(vmap_area_lock);
[   50.827086]   <Interrupt>
[   50.829823]     lock(&(&pool->lock)->rlock#2);
[   50.834490]
[   50.834490]  *** DEADLOCK ***
[   50.834490]
[   50.840695] 4 locks held by modprobe/1921:
[   50.844981]  #0:  (&__lockdep_no_validate__){......}, at: [<c03e53e8>] driver_detach+0x44/0xb8
[   50.854038]  #1:  (&__lockdep_no_validate__){......}, at: [<c03e53f4>] driver_detach+0x50/0xb8
[   50.863102]  #2:  (&(&ctlr->lock)->rlock){......}, at: [<bf017c34>] cpdma_ctlr_destroy+0x1c/0x114 [davinci_cpdma]
[   50.873890]  #3:  (&(&pool->lock)->rlock#2){..-...}, at: [<bf017c74>] cpdma_ctlr_destroy+0x5c/0x114 [davinci_cpdma]
[   50.884871]
the dependencies between SOFTIRQ-irq-safe lock and the holding lock:
[   50.892827] -> (&(&pool->lock)->rlock#2){..-...} ops: 167 {
[   50.898703]    IN-SOFTIRQ-W at:
[   50.901995]                     [<c06585a4>] _raw_spin_lock_irqsave+0x38/0x4c
[   50.909476]                     [<bf01773c>] cpdma_desc_free.constprop.7+0x28/0x58 [davinci_cpdma]
[   50.918878]                     [<bf0177e8>] __cpdma_chan_free+0x7c/0xa8 [davinci_cpdma]
[   50.927366]                     [<bf017908>] __cpdma_chan_process+0xf4/0x134 [davinci_cpdma]
[   50.936218]                     [<bf017984>] cpdma_chan_process+0x3c/0x54 [davinci_cpdma]
[   50.944794]                     [<bf0277e8>] cpsw_poll+0x14/0xa8 [ti_cpsw]
[   50.952009]                     [<c05844f4>] net_rx_action+0xc0/0x1e8
[   50.958765]                     [<c0048234>] __do_softirq+0xcc/0x304
[   50.965432]                     [<c004873c>] irq_exit+0xa8/0xfc
[   50.971635]                     [<c000eeac>] handle_IRQ+0x50/0xb0
[   50.978035]                     [<c0008638>] gic_handle_irq+0x28/0x5c
[   50.984788]                     [<c06590a4>] __irq_svc+0x44/0x5c
[   50.991085]                     [<c0658ab4>] _raw_spin_unlock_irqrestore+0x34/0x44
[   50.999023]                     [<c065a9c4>] do_page_fault.part.9+0x144/0x3c4
[   51.006510]                     [<c065acb8>] do_page_fault+0x74/0x84
[   51.013171]                     [<c00083dc>] do_DataAbort+0x34/0x98
[   51.019738]                     [<c065923c>] __dabt_usr+0x3c/0x40
[   51.026129]    INITIAL USE at:
[   51.029335]                    [<c06585a4>] _raw_spin_lock_irqsave+0x38/0x4c
[   51.036729]                    [<bf017d78>] cpdma_chan_submit+0x4c/0x2f0 [davinci_cpdma]
[   51.045225]                    [<bf02863c>] cpsw_ndo_open+0x378/0x6bc [ti_cpsw]
[   51.052897]                    [<c058747c>] __dev_open+0x9c/0x104
[   51.059287]                    [<c05876ec>] __dev_change_flags+0x88/0x160
[   51.066420]                    [<c05877e4>] dev_change_flags+0x18/0x48
[   51.073270]                    [<c05ed51c>] devinet_ioctl+0x61c/0x6e0
[   51.080029]                    [<c056ee54>] sock_ioctl+0x5c/0x298
[   51.086418]                    [<c01350a4>] do_vfs_ioctl+0x78/0x61c
[   51.092993]                    [<c01356ac>] SyS_ioctl+0x64/0x74
[   51.099200]                    [<c000e580>] ret_fast_syscall+0x0/0x48
[   51.105956]  }
[   51.107696]  ... key      at: [<bf019000>] __key.21312+0x0/0xfffff650 [davinci_cpdma]
[   51.115912]  ... acquired at:
[   51.119019]    [<c00899ac>] lock_acquire+0x9c/0x104
[   51.124138]    [<c06584e8>] _raw_spin_lock+0x28/0x38
[   51.129341]    [<c01127fc>] find_vmap_area+0x10/0x6c
[   51.134547]    [<c0114960>] remove_vm_area+0x8/0x6c
[   51.139659]    [<c0114a7c>] __vunmap+0x20/0xf8
[   51.144318]    [<c001c350>] __arm_iounmap+0x10/0x18
[   51.149440]    [<bf017d08>] cpdma_ctlr_destroy+0xf0/0x114 [davinci_cpdma]
[   51.156560]    [<bf026294>] cpsw_remove+0x48/0x8c [ti_cpsw]
[   51.162407]    [<c03e62c8>] platform_drv_remove+0x18/0x1c
[   51.168063]    [<c03e4c44>] __device_release_driver+0x70/0xc8
[   51.174094]    [<c03e5458>] driver_detach+0xb4/0xb8
[   51.179212]    [<c03e4a6c>] bus_remove_driver+0x4c/0x90
[   51.184693]    [<c00b024c>] SyS_delete_module+0x10c/0x198
[   51.190355]    [<c000e580>] ret_fast_syscall+0x0/0x48
[   51.195661]
[   51.197217]
the dependencies between the lock to be acquired and SOFTIRQ-irq-unsafe lock:
[   51.205986] -> (vmap_area_lock){+.+...} ops: 520 {
[   51.211032]    HARDIRQ-ON-W at:
[   51.214321]                     [<c06584e8>] _raw_spin_lock+0x28/0x38
[   51.221090]                     [<c011376c>] alloc_vmap_area.isra.28+0xb8/0x300
[   51.228750]                     [<c0113a44>] __get_vm_area_node.isra.29+0x90/0x134
[   51.236690]                     [<c011486c>] get_vm_area_caller+0x3c/0x48
[   51.243811]                     [<c0114be0>] vmap+0x40/0x78
[   51.249654]                     [<c09442f0>] check_writebuffer_bugs+0x54/0x1a0
[   51.257239]                     [<c093eac0>] start_kernel+0x320/0x388
[   51.263994]                     [<80008074>] 0x80008074
[   51.269474]    SOFTIRQ-ON-W at:
[   51.272769]                     [<c06584e8>] _raw_spin_lock+0x28/0x38
[   51.279525]                     [<c011376c>] alloc_vmap_area.isra.28+0xb8/0x300
[   51.287190]                     [<c0113a44>] __get_vm_area_node.isra.29+0x90/0x134
[   51.295126]                     [<c011486c>] get_vm_area_caller+0x3c/0x48
[   51.302245]                     [<c0114be0>] vmap+0x40/0x78
[   51.308094]                     [<c09442f0>] check_writebuffer_bugs+0x54/0x1a0
[   51.315669]                     [<c093eac0>] start_kernel+0x320/0x388
[   51.322423]                     [<80008074>] 0x80008074
[   51.327906]    INITIAL USE at:
[   51.331112]                    [<c06584e8>] _raw_spin_lock+0x28/0x38
[   51.337775]                    [<c011376c>] alloc_vmap_area.isra.28+0xb8/0x300
[   51.345352]                    [<c0113a44>] __get_vm_area_node.isra.29+0x90/0x134
[   51.353197]                    [<c011486c>] get_vm_area_caller+0x3c/0x48
[   51.360224]                    [<c0114be0>] vmap+0x40/0x78
[   51.365977]                    [<c09442f0>] check_writebuffer_bugs+0x54/0x1a0
[   51.373464]                    [<c093eac0>] start_kernel+0x320/0x388
[   51.380131]                    [<80008074>] 0x80008074
[   51.385517]  }
[   51.387260]  ... key      at: [<c0a66948>] vmap_area_lock+0x10/0x20
[   51.393841]  ... acquired at:
[   51.396945]    [<c00899ac>] lock_acquire+0x9c/0x104
[   51.402060]    [<c06584e8>] _raw_spin_lock+0x28/0x38
[   51.407266]    [<c01127fc>] find_vmap_area+0x10/0x6c
[   51.412478]    [<c0114960>] remove_vm_area+0x8/0x6c
[   51.417592]    [<c0114a7c>] __vunmap+0x20/0xf8
[   51.422252]    [<c001c350>] __arm_iounmap+0x10/0x18
[   51.427369]    [<bf017d08>] cpdma_ctlr_destroy+0xf0/0x114 [davinci_cpdma]
[   51.434487]    [<bf026294>] cpsw_remove+0x48/0x8c [ti_cpsw]
[   51.440336]    [<c03e62c8>] platform_drv_remove+0x18/0x1c
[   51.446000]    [<c03e4c44>] __device_release_driver+0x70/0xc8
[   51.452031]    [<c03e5458>] driver_detach+0xb4/0xb8
[   51.457147]    [<c03e4a6c>] bus_remove_driver+0x4c/0x90
[   51.462628]    [<c00b024c>] SyS_delete_module+0x10c/0x198
[   51.468289]    [<c000e580>] ret_fast_syscall+0x0/0x48
[   51.473584]
[   51.475140]
[   51.475140] stack backtrace:
[   51.479703] CPU: 0 PID: 1921 Comm: modprobe Not tainted 3.14.19-02124-g95c5b7b torvalds#308
[   51.487744] [<c0016090>] (unwind_backtrace) from [<c0012060>] (show_stack+0x10/0x14)
[   51.495865] [<c0012060>] (show_stack) from [<c0652a20>] (dump_stack+0x78/0x94)
[   51.503444] [<c0652a20>] (dump_stack) from [<c0086f18>] (check_usage+0x408/0x594)
[   51.511293] [<c0086f18>] (check_usage) from [<c00870f8>] (check_irq_usage+0x54/0xb0)
[   51.519416] [<c00870f8>] (check_irq_usage) from [<c0088724>] (__lock_acquire+0xe54/0x1b90)
[   51.528077] [<c0088724>] (__lock_acquire) from [<c00899ac>] (lock_acquire+0x9c/0x104)
[   51.536291] [<c00899ac>] (lock_acquire) from [<c06584e8>] (_raw_spin_lock+0x28/0x38)
[   51.544417] [<c06584e8>] (_raw_spin_lock) from [<c01127fc>] (find_vmap_area+0x10/0x6c)
[   51.552726] [<c01127fc>] (find_vmap_area) from [<c0114960>] (remove_vm_area+0x8/0x6c)
[   51.560935] [<c0114960>] (remove_vm_area) from [<c0114a7c>] (__vunmap+0x20/0xf8)
[   51.568693] [<c0114a7c>] (__vunmap) from [<c001c350>] (__arm_iounmap+0x10/0x18)
[   51.576362] [<c001c350>] (__arm_iounmap) from [<bf017d08>] (cpdma_ctlr_destroy+0xf0/0x114 [davinci_cpdma])
[   51.586494] [<bf017d08>] (cpdma_ctlr_destroy [davinci_cpdma]) from [<bf026294>] (cpsw_remove+0x48/0x8c [ti_cpsw])
[   51.597261] [<bf026294>] (cpsw_remove [ti_cpsw]) from [<c03e62c8>] (platform_drv_remove+0x18/0x1c)
[   51.606659] [<c03e62c8>] (platform_drv_remove) from [<c03e4c44>] (__device_release_driver+0x70/0xc8)
[   51.616237] [<c03e4c44>] (__device_release_driver) from [<c03e5458>] (driver_detach+0xb4/0xb8)
[   51.625264] [<c03e5458>] (driver_detach) from [<c03e4a6c>] (bus_remove_driver+0x4c/0x90)
[   51.633749] [<c03e4a6c>] (bus_remove_driver) from [<c00b024c>] (SyS_delete_module+0x10c/0x198)
[   51.642781] [<c00b024c>] (SyS_delete_module) from [<c000e580>] (ret_fast_syscall+0x0/0x48)

Signed-off-by: Mugunthan V N <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
tom3q pushed a commit that referenced this pull request Oct 26, 2014
A panic was seen in the following sitation.

There are two threads running on the system. The first thread is a system
monitoring thread that is reading /proc/modules. The second thread is
loading and unloading a module (in this example I'm using my simple
dummy-module.ko).  Note, in the "real world" this occurred with the qlogic
driver module.

When doing this, the following panic occurred:

 ------------[ cut here ]------------
 kernel BUG at kernel/module.c:3739!
 invalid opcode: 0000 [#1] SMP
 Modules linked in: binfmt_misc sg nfsv3 rpcsec_gss_krb5 nfsv4 dns_resolver nfs fscache intel_powerclamp coretemp kvm_intel kvm crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel aesni_intel lrw igb gf128mul glue_helper iTCO_wdt iTCO_vendor_support ablk_helper ptp sb_edac cryptd pps_core edac_core shpchp i2c_i801 pcspkr wmi lpc_ich ioatdma mfd_core dca ipmi_si nfsd ipmi_msghandler auth_rpcgss nfs_acl lockd sunrpc xfs libcrc32c sr_mod cdrom sd_mod crc_t10dif crct10dif_common mgag200 syscopyarea sysfillrect sysimgblt i2c_algo_bit drm_kms_helper ttm isci drm libsas ahci libahci scsi_transport_sas libata i2c_core dm_mirror dm_region_hash dm_log dm_mod [last unloaded: dummy_module]
 CPU: 37 PID: 186343 Comm: cat Tainted: GF          O--------------   3.10.0+ torvalds#7
 Hardware name: Intel Corporation S2600CP/S2600CP, BIOS RMLSDP.86I.00.29.D696.1311111329 11/11/2013
 task: ffff8807fd2d8000 ti: ffff88080fa7c000 task.ti: ffff88080fa7c000
 RIP: 0010:[<ffffffff810d64c5>]  [<ffffffff810d64c5>] module_flags+0xb5/0xc0
 RSP: 0018:ffff88080fa7fe18  EFLAGS: 00010246
 RAX: 0000000000000003 RBX: ffffffffa03b5200 RCX: 0000000000000000
 RDX: 0000000000001000 RSI: ffff88080fa7fe38 RDI: ffffffffa03b5000
 RBP: ffff88080fa7fe28 R08: 0000000000000010 R09: 0000000000000000
 R10: 0000000000000000 R11: 000000000000000f R12: ffffffffa03b5000
 R13: ffffffffa03b5008 R14: ffffffffa03b5200 R15: ffffffffa03b5000
 FS:  00007f6ae57ef740(0000) GS:ffff88101e7a0000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000404f70 CR3: 0000000ffed48000 CR4: 00000000001407e0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
 Stack:
  ffffffffa03b5200 ffff8810101e4800 ffff88080fa7fe70 ffffffff810d666c
  ffff88081e807300 000000002e0f2fbf 0000000000000000 ffff88100f257b00
  ffffffffa03b5008 ffff88080fa7ff48 ffff8810101e4800 ffff88080fa7fee0
 Call Trace:
  [<ffffffff810d666c>] m_show+0x19c/0x1e0
  [<ffffffff811e4d7e>] seq_read+0x16e/0x3b0
  [<ffffffff812281ed>] proc_reg_read+0x3d/0x80
  [<ffffffff811c0f2c>] vfs_read+0x9c/0x170
  [<ffffffff811c1a58>] SyS_read+0x58/0xb0
  [<ffffffff81605829>] system_call_fastpath+0x16/0x1b
 Code: 48 63 c2 83 c2 01 c6 04 03 29 48 63 d2 eb d9 0f 1f 80 00 00 00 00 48 63 d2 c6 04 13 2d 41 8b 0c 24 8d 50 02 83 f9 01 75 b2 eb cb <0f> 0b 66 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 41
 RIP  [<ffffffff810d64c5>] module_flags+0xb5/0xc0
  RSP <ffff88080fa7fe18>

    Consider the two processes running on the system.

    CPU 0 (/proc/modules reader)
    CPU 1 (loading/unloading module)

    CPU 0 opens /proc/modules, and starts displaying data for each module by
    traversing the modules list via fs/seq_file.c:seq_open() and
    fs/seq_file.c:seq_read().  For each module in the modules list, seq_read
    does

            op->start()  <-- this is a pointer to m_start()
            op->show()   <- this is a pointer to m_show()
            op->stop()   <-- this is a pointer to m_stop()

    The m_start(), m_show(), and m_stop() module functions are defined in
    kernel/module.c. The m_start() and m_stop() functions acquire and release
    the module_mutex respectively.

    ie) When reading /proc/modules, the module_mutex is acquired and released
    for each module.

    m_show() is called with the module_mutex held.  It accesses the module
    struct data and attempts to write out module data.  It is in this code
    path that the above BUG_ON() warning is encountered, specifically m_show()
    calls

    static char *module_flags(struct module *mod, char *buf)
    {
            int bx = 0;

            BUG_ON(mod->state == MODULE_STATE_UNFORMED);
    ...

    The other thread, CPU 1, in unloading the module calls the syscall
    delete_module() defined in kernel/module.c.  The module_mutex is acquired
    for a short time, and then released.  free_module() is called without the
    module_mutex.  free_module() then sets mod->state = MODULE_STATE_UNFORMED,
    also without the module_mutex.  Some additional code is called and then the
    module_mutex is reacquired to remove the module from the modules list:

        /* Now we can delete it from the lists */
        mutex_lock(&module_mutex);
        stop_machine(__unlink_module, mod, NULL);
        mutex_unlock(&module_mutex);

This is the sequence of events that leads to the panic.

CPU 1 is removing dummy_module via delete_module().  It acquires the
module_mutex, and then releases it.  CPU 1 has NOT set dummy_module->state to
MODULE_STATE_UNFORMED yet.

CPU 0, which is reading the /proc/modules, acquires the module_mutex and
acquires a pointer to the dummy_module which is still in the modules list.
CPU 0 calls m_show for dummy_module.  The check in m_show() for
MODULE_STATE_UNFORMED passed for dummy_module even though it is being
torn down.

Meanwhile CPU 1, which has been continuing to remove dummy_module without
holding the module_mutex, now calls free_module() and sets
dummy_module->state to MODULE_STATE_UNFORMED.

CPU 0 now calls module_flags() with dummy_module and ...

static char *module_flags(struct module *mod, char *buf)
{
        int bx = 0;

        BUG_ON(mod->state == MODULE_STATE_UNFORMED);

and BOOM.

Acquire and release the module_mutex lock around the setting of
MODULE_STATE_UNFORMED in the teardown path, which should resolve the
problem.

Testing: In the unpatched kernel I can panic the system within 1 minute by
doing

while (true) do insmod dummy_module.ko; rmmod dummy_module.ko; done

and

while (true) do cat /proc/modules; done

in separate terminals.

In the patched kernel I was able to run just over one hour without seeing
any issues.  I also verified the output of panic via sysrq-c and the output
of /proc/modules looks correct for all three states for the dummy_module.

        dummy_module 12661 0 - Unloading 0xffffffffa03a5000 (OE-)
        dummy_module 12661 0 - Live 0xffffffffa03bb000 (OE)
        dummy_module 14015 1 - Loading 0xffffffffa03a5000 (OE+)

Signed-off-by: Prarit Bhargava <[email protected]>
Reviewed-by: Oleg Nesterov <[email protected]>
Signed-off-by: Rusty Russell <[email protected]>
Cc: [email protected]
tom3q pushed a commit that referenced this pull request Oct 26, 2014
For commit ocfs2 journal, ocfs2 journal thread will acquire the mutex
osb->journal->j_trans_barrier and wake up jbd2 commit thread, then it
will wait until jbd2 commit thread done. In order journal mode, jbd2
needs flushing dirty data pages first, and this needs get page lock.
So osb->journal->j_trans_barrier should be got before page lock.

But ocfs2_write_zero_page() and ocfs2_write_begin_inline() obey this
locking order, and this will cause deadlock and hung the whole cluster.

One deadlock catched is the following:

PID: 13449  TASK: ffff8802e2f08180  CPU: 31  COMMAND: "oracle"
 #0 [ffff8802ee3f79b0] __schedule at ffffffff8150a524
 #1 [ffff8802ee3f7a58] schedule at ffffffff8150acbf
 #2 [ffff8802ee3f7a68] rwsem_down_failed_common at ffffffff8150cb85
 #3 [ffff8802ee3f7ad8] rwsem_down_read_failed at ffffffff8150cc55
 #4 [ffff8802ee3f7ae8] call_rwsem_down_read_failed at ffffffff812617a4
 #5 [ffff8802ee3f7b50] ocfs2_start_trans at ffffffffa0498919 [ocfs2]
 torvalds#6 [ffff8802ee3f7ba0] ocfs2_zero_start_ordered_transaction at ffffffffa048b2b8 [ocfs2]
 torvalds#7 [ffff8802ee3f7bf0] ocfs2_write_zero_page at ffffffffa048e9bd [ocfs2]
 torvalds#8 [ffff8802ee3f7c80] ocfs2_zero_extend_range at ffffffffa048ec83 [ocfs2]
 torvalds#9 [ffff8802ee3f7ce0] ocfs2_zero_extend at ffffffffa048edfd [ocfs2]
 torvalds#10 [ffff8802ee3f7d50] ocfs2_extend_file at ffffffffa049079e [ocfs2]
 torvalds#11 [ffff8802ee3f7da0] ocfs2_setattr at ffffffffa04910ed [ocfs2]
 torvalds#12 [ffff8802ee3f7e70] notify_change at ffffffff81187d29
 torvalds#13 [ffff8802ee3f7ee0] do_truncate at ffffffff8116bbc1
 torvalds#14 [ffff8802ee3f7f50] sys_ftruncate at ffffffff8116bcbd
 torvalds#15 [ffff8802ee3f7f80] system_call_fastpath at ffffffff81515142
    RIP: 00007f8de750c6f7  RSP: 00007fffe786e478  RFLAGS: 00000206
    RAX: 000000000000004d  RBX: ffffffff81515142  RCX: 0000000000000000
    RDX: 0000000000000200  RSI: 0000000000028400  RDI: 000000000000000d
    RBP: 00007fffe786e040   R8: 0000000000000000   R9: 000000000000000d
    R10: 0000000000000000  R11: 0000000000000206  R12: 000000000000000d
    R13: 00007fffe786e710  R14: 00007f8de70f8340  R15: 0000000000028400
    ORIG_RAX: 000000000000004d  CS: 0033  SS: 002b

crash64> bt
PID: 7610   TASK: ffff88100fd56140  CPU: 1   COMMAND: "ocfs2cmt"
 #0 [ffff88100f4d1c50] __schedule at ffffffff8150a524
 #1 [ffff88100f4d1cf8] schedule at ffffffff8150acbf
 #2 [ffff88100f4d1d08] jbd2_log_wait_commit at ffffffffa01274fd [jbd2]
 #3 [ffff88100f4d1d98] jbd2_journal_flush at ffffffffa01280b4 [jbd2]
 #4 [ffff88100f4d1dd8] ocfs2_commit_cache at ffffffffa0499b14 [ocfs2]
 #5 [ffff88100f4d1e38] ocfs2_commit_thread at ffffffffa0499d38 [ocfs2]
 torvalds#6 [ffff88100f4d1ee8] kthread at ffffffff81090db6
 torvalds#7 [ffff88100f4d1f48] kernel_thread_helper at ffffffff81516284

crash64> bt
PID: 7609   TASK: ffff88100f2d4480  CPU: 0   COMMAND: "jbd2/dm-20-86"
 #0 [ffff88100def3920] __schedule at ffffffff8150a524
 #1 [ffff88100def39c8] schedule at ffffffff8150acbf
 #2 [ffff88100def39d8] io_schedule at ffffffff8150ad6c
 #3 [ffff88100def39f8] sleep_on_page at ffffffff8111069e
 #4 [ffff88100def3a08] __wait_on_bit_lock at ffffffff8150b30a
 #5 [ffff88100def3a58] __lock_page at ffffffff81110687
 torvalds#6 [ffff88100def3ab8] write_cache_pages at ffffffff8111b752
 torvalds#7 [ffff88100def3be8] generic_writepages at ffffffff8111b901
 torvalds#8 [ffff88100def3c48] journal_submit_data_buffers at ffffffffa0120f67 [jbd2]
 torvalds#9 [ffff88100def3cf8] jbd2_journal_commit_transaction at ffffffffa0121372[jbd2]
 torvalds#10 [ffff88100def3e68] kjournald2 at ffffffffa0127a86 [jbd2]
 torvalds#11 [ffff88100def3ee8] kthread at ffffffff81090db6
 torvalds#12 [ffff88100def3f48] kernel_thread_helper at ffffffff81516284

Signed-off-by: Junxiao Bi <[email protected]>
Cc: Mark Fasheh <[email protected]>
Cc: Joel Becker <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
tom3q pushed a commit that referenced this pull request Oct 26, 2014
cat /sys/.../pools followed by removal the device leads to:

|======================================================
|[ INFO: possible circular locking dependency detected ]
|3.17.0-rc4+ #1498 Not tainted
|-------------------------------------------------------
|rmmod/2505 is trying to acquire lock:
| (s_active#28){++++.+}, at: [<c017f754>] kernfs_remove_by_name_ns+0x3c/0x88
|
|but task is already holding lock:
| (pools_lock){+.+.+.}, at: [<c011494c>] dma_pool_destroy+0x18/0x17c
|
|which lock already depends on the new lock.
|the existing dependency chain (in reverse order) is:
|
|-> #1 (pools_lock){+.+.+.}:
|   [<c0114ae8>] show_pools+0x30/0xf8
|   [<c0313210>] dev_attr_show+0x1c/0x48
|   [<c0180e84>] sysfs_kf_seq_show+0x88/0x10c
|   [<c017f960>] kernfs_seq_show+0x24/0x28
|   [<c013efc4>] seq_read+0x1b8/0x480
|   [<c011e820>] vfs_read+0x8c/0x148
|   [<c011ea10>] SyS_read+0x40/0x8c
|   [<c000e960>] ret_fast_syscall+0x0/0x48
|
|-> #0 (s_active#28){++++.+}:
|   [<c017e9ac>] __kernfs_remove+0x258/0x2ec
|   [<c017f754>] kernfs_remove_by_name_ns+0x3c/0x88
|   [<c0114a7c>] dma_pool_destroy+0x148/0x17c
|   [<c03ad288>] hcd_buffer_destroy+0x20/0x34
|   [<c03a4780>] usb_remove_hcd+0x110/0x1a4

The problem is the lock order of pools_lock and kernfs_mutex in
dma_pool_destroy() vs show_pools() call path.

This patch breaks out the creation of the sysfs file outside of the
pools_lock mutex.  The newly added pools_reg_lock ensures that there is no
race of create vs destroy code path in terms whether or not the sysfs file
has to be deleted (and was it deleted before we try to create a new one)
and what to do if device_create_file() failed.

Signed-off-by: Sebastian Andrzej Siewior <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
tom3q pushed a commit that referenced this pull request Oct 26, 2014
…heck

If the type we receive is greater than ST_MAX_CHANNELS we can't rely on
type as vector index since we would be accessing unknown memory when we use the type
as index.

 Unable to handle kernel NULL pointer dereference at virtual address 0000001b
 pgd = c0004000
 [0000001b] *pgd=00000000
 Internal error: Oops: 17 [#1] PREEMPT SMP ARM
 Modules linked in: btwilink wl12xx wlcore mac80211 cfg80211 rfcomm bnep bluo
 CPU: 0    Tainted: G        W     (3.4.0+ torvalds#15)
 PC is at st_int_recv+0x278/0x344
 LR is at get_parent_ip+0x14/0x30
 pc : [<c03b01a8>]    lr : [<c007273c>]    psr: 200f0193
 sp : dc631ed0  ip : e3e21c24  fp : dc631f04
 r10: 00000000  r9 : 600f0113  r8 : 0000003f
 r7 : e3e21b14  r6 : 00000067  r5 : e2e49c1c  r4 : e3e21a80
 r3 : 00000001  r2 : 00000001  r1 : 00000001  r0 : 600f0113
 Flags: nzCv  IRQs off  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
 Control: 10c5387d  Table: 9c50004a  DAC: 00000015

Signed-off-by: Gustavo Padovan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
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