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Inital merge from Linux source tree 2.6.31.9 to 2.6.32 for aNCR #1

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Puneeth-n
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implementation.

@Puneeth-n Puneeth-n closed this Mar 28, 2014
@Puneeth-n Puneeth-n deleted the 2.6.32.x-tcp-ancr-to-merge branch April 1, 2014 14:30
Puneeth-n pushed a commit to Puneeth-n/linux that referenced this pull request Apr 17, 2014
When encountering memory pressure, testers have run into the following
lockdep warning. It was caused by __link_block_group calling kobject_add
with the groups_sem held. kobject_add calls kvasprintf with GFP_KERNEL,
which gets us into reclaim context. The kobject doesn't actually need
to be added under the lock -- it just needs to ensure that it's only
added for the first block group to be linked.

=========================================================
[ INFO: possible irq lock inversion dependency detected ]
3.14.0-rc8-default alexander-zimmermann#1 Not tainted
---------------------------------------------------------
kswapd0/169 just changed the state of lock:
 (&delayed_node->mutex){+.+.-.}, at: [<ffffffffa018baea>] __btrfs_release_delayed_node+0x3a/0x200 [btrfs]
but this lock took another, RECLAIM_FS-unsafe lock in the past:
 (&found->groups_sem){+++++.}

and interrupts could create inverse lock ordering between them.

other info that might help us debug this:
 Possible interrupt unsafe locking scenario:
       CPU0                    CPU1
       ----                    ----
  lock(&found->groups_sem);
                               local_irq_disable();
                               lock(&delayed_node->mutex);
                               lock(&found->groups_sem);
  <Interrupt>
    lock(&delayed_node->mutex);

 *** DEADLOCK ***
2 locks held by kswapd0/169:
 #0:  (shrinker_rwsem){++++..}, at: [<ffffffff81159e8a>] shrink_slab+0x3a/0x160
 alexander-zimmermann#1:  (&type->s_umount_key#27){++++..}, at: [<ffffffff811bac6f>] grab_super_passive+0x3f/0x90

Signed-off-by: Jeff Mahoney <[email protected]>
Signed-off-by: Chris Mason <[email protected]>
Puneeth-n pushed a commit to Puneeth-n/linux that referenced this pull request Apr 17, 2014
The code didn't verify that a control channel exists before trying to
use it. It caused NULL ptr derefs which were easy to trigger by an
unpriviliged user simply by reading the proc file, causing:

[   68.161404] BUG: unable to handle kernel NULL pointer dereference at           (null)
[   68.162442] IP: visorchannel_read (drivers/staging/unisys/visorchannel/visorchannel_funcs.c:225)
[   68.163165] PGD 5ca21067 PUD 5ca20067 PMD 0
[   68.163712] Oops: 0000 [alexander-zimmermann#1] PREEMPT SMP DEBUG_PAGEALLOC
[   68.164390] Dumping ftrace buffer:
[   68.164793]    (ftrace buffer empty)
[   68.165220] Modules linked in:
[   68.165601] CPU: 0 PID: 7915 Comm: cat Tainted: G        W     3.14.0-next-20140403-sasha-00012-gef5fa7d-dirty torvalds#373
[   68.166821] task: ffff88006e8c3000 ti: ffff88005ca30000 task.ti: ffff88005ca30000
[   68.167689] RIP: visorchannel_read (drivers/staging/unisys/visorchannel/visorchannel_funcs.c:225)
[   68.168683] RSP: 0018:ffff88005ca31e58  EFLAGS: 00010282
[   68.169302] RAX: ffff88005ca10000 RBX: ffff88005ca31e97 RCX: 0000000000000001
[   68.170019] RDX: ffff88005ca31e97 RSI: 0000000000000bd6 RDI: 0000000000000000
[   68.170019] RBP: ffff88005ca31e78 R08: 0000000000000000 R09: 0000000000000000
[   68.170019] R10: ffff880000000000 R11: 0000000000000001 R12: 0000000000000001
[   68.170019] R13: 0000000000000bd6 R14: 0000000000000000 R15: 0000000000008000
[   68.170019] FS:  00007f0e8c041700(0000) GS:ffff88007be00000(0000) knlGS:0000000000000000
[   68.170019] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   68.170019] CR2: 0000000000000000 CR3: 000000006efe9000 CR4: 00000000000006b0
[   68.170019] Stack:
[   68.170019]  ffff88005ca31f50 ffff88005ca10000 000000000060e000 ffff88005ca31f50
[   68.170019]  ffff88005ca31ec8 ffffffff83e6f983 ffff8800780db810 0000000000008000
[   68.170019]  ffff88005ca31ec8 ffff88006da5f908 ffff8800780db800 000000000060e000
[   68.170019] Call Trace:
[   68.170019] proc_read_toolaction (drivers/staging/unisys/visorchipset/visorchipset_main.c:2541)
[   68.170019] proc_reg_read (fs/proc/inode.c:211)
[   68.170019] vfs_read (fs/read_write.c:408)
[   68.170019] SyS_read (fs/read_write.c:519 fs/read_write.c:511)
[   68.170019] tracesys (arch/x86/kernel/entry_64.S:749)
[   68.170019] Code: 00 00 66 66 66 66 90 55 48 89 e5 48 83 ec 20 48 89 5d e0 48 89 d3 4c 89 65 e8 49 89 cc 4c 89 6d f0 49 89 f5 4c 89 75 f8 49 89 fe <48> 8b 3f e8 4f f9 ff ff 85 c0 0f 88 97 00 00 00 4d 85 ed 0f 85
[   68.170019] RIP visorchannel_read (drivers/staging/unisys/visorchannel/visorchannel_funcs.c:225)
[   68.170019]  RSP <ffff88005ca31e58>
[   68.170019] CR2: 0000000000000000

Signed-off-by: Sasha Levin <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Puneeth-n pushed a commit to Puneeth-n/linux that referenced this pull request Apr 17, 2014
…anges

Sasha reported the following bug using trinity

  kernel BUG at mm/mprotect.c:149!
  invalid opcode: 0000 [alexander-zimmermann#1] PREEMPT SMP DEBUG_PAGEALLOC
  Dumping ftrace buffer:
     (ftrace buffer empty)
  Modules linked in:
  CPU: 20 PID: 26219 Comm: trinity-c216 Tainted: G        W    3.14.0-rc5-next-20140305-sasha-00011-ge06f5f3-dirty torvalds#105
  task: ffff8800b6c80000 ti: ffff880228436000 task.ti: ffff880228436000
  RIP: change_protection_range+0x3b3/0x500
  Call Trace:
    change_protection+0x25/0x30
    change_prot_numa+0x1b/0x30
    task_numa_work+0x279/0x360
    task_work_run+0xae/0xf0
    do_notify_resume+0x8e/0xe0
    retint_signal+0x4d/0x92

The VM_BUG_ON was added in -mm by the patch "mm,numa: reorganize
change_pmd_range".  The race existed without the patch but was just
harder to hit.

The problem is that a transhuge check is made without holding the PTL.
It's possible at the time of the check that a parallel fault clears the
pmd and inserts a new one which then triggers the VM_BUG_ON check.  This
patch removes the VM_BUG_ON but fixes the race by rechecking transhuge
under the PTL when marking page tables for NUMA hinting and bailing if a
race occurred.  It is not a problem for calls to mprotect() as they hold
mmap_sem for write.

Signed-off-by: Mel Gorman <[email protected]>
Reported-by: Sasha Levin <[email protected]>
Reviewed-by: Rik van Riel <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Puneeth-n pushed a commit to Puneeth-n/linux that referenced this pull request Apr 17, 2014
When I decrease the value of nr_hugepage in procfs a lot, softlockup
happens.  It is because there is no chance of context switch during this
process.

On the other hand, when I allocate a large number of hugepages, there is
some chance of context switch.  Hence softlockup doesn't happen during
this process.  So it's necessary to add the context switch in the
freeing process as same as allocating process to avoid softlockup.

When I freed 12 TB hugapages with kernel-2.6.32-358.el6, the freeing
process occupied a CPU over 150 seconds and following softlockup message
appeared twice or more.

$ echo 6000000 > /proc/sys/vm/nr_hugepages
$ cat /proc/sys/vm/nr_hugepages
6000000
$ grep ^Huge /proc/meminfo
HugePages_Total:   6000000
HugePages_Free:    6000000
HugePages_Rsvd:        0
HugePages_Surp:        0
Hugepagesize:       2048 kB
$ echo 0 > /proc/sys/vm/nr_hugepages

BUG: soft lockup - CPU#16 stuck for 67s! [sh:12883] ...
Pid: 12883, comm: sh Not tainted 2.6.32-358.el6.x86_64 alexander-zimmermann#1
Call Trace:
  free_pool_huge_page+0xb8/0xd0
  set_max_huge_pages+0x128/0x190
  hugetlb_sysctl_handler_common+0x113/0x140
  hugetlb_sysctl_handler+0x1e/0x20
  proc_sys_call_handler+0x97/0xd0
  proc_sys_write+0x14/0x20
  vfs_write+0xb8/0x1a0
  sys_write+0x51/0x90
  __audit_syscall_exit+0x265/0x290
  system_call_fastpath+0x16/0x1b

I have not confirmed this problem with upstream kernels because I am not
able to prepare the machine equipped with 12TB memory now.  However I
confirmed that the amount of decreasing hugepages was directly
proportional to the amount of required time.

I measured required times on a smaller machine.  It showed 130-145
hugepages decreased in a millisecond.

  Amount of decreasing     Required time      Decreasing rate
  hugepages                     (msec)         (pages/msec)
  ------------------------------------------------------------
  10,000 pages == 20GB         70 -  74          135-142
  30,000 pages == 60GB        208 - 229          131-144

It means decrement of 6TB hugepages will trigger softlockup with the
default threshold 20sec, in this decreasing rate.

Signed-off-by: Masayoshi Mizuma <[email protected]>
Cc: Joonsoo Kim <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Wanpeng Li <[email protected]>
Cc: Aneesh Kumar <[email protected]>
Cc: KOSAKI Motohiro <[email protected]>
Cc: Naoya Horiguchi <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Puneeth-n pushed a commit to Puneeth-n/linux that referenced this pull request Apr 17, 2014
nf_ct_gre_keymap_flush() removes a nf_ct_gre_keymap object from
net_gre->keymap_list and frees the object. But it doesn't clean
a reference on this object from ct_pptp_info->keymap[dir].
Then nf_ct_gre_keymap_destroy() may release the same object again.

So nf_ct_gre_keymap_flush() can be called only when we are sure that
when nf_ct_gre_keymap_destroy will not be called.

nf_ct_gre_keymap is created by nf_ct_gre_keymap_add() and the right way
to destroy it is to call nf_ct_gre_keymap_destroy().

This patch marks nf_ct_gre_keymap_flush() as static, so this patch can
break compilation of third party modules, which use
nf_ct_gre_keymap_flush. I'm not sure this is the right way to deprecate
this function.

[  226.540793] general protection fault: 0000 [alexander-zimmermann#1] SMP
[  226.541750] Modules linked in: nf_nat_pptp nf_nat_proto_gre
nf_conntrack_pptp nf_conntrack_proto_gre ip_gre ip_tunnel gre
ppp_deflate bsd_comp ppp_async crc_ccitt ppp_generic slhc xt_nat
iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat
nf_conntrack veth tun bridge stp llc ppdev microcode joydev pcspkr
serio_raw virtio_console virtio_balloon floppy parport_pc parport
pvpanic i2c_piix4 virtio_net drm_kms_helper ttm ata_generic virtio_pci
virtio_ring virtio drm i2c_core pata_acpi [last unloaded: ip_tunnel]
[  226.541776] CPU: 0 PID: 49 Comm: kworker/u4:2 Not tainted 3.14.0-rc8+ torvalds#101
[  226.541776] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[  226.541776] Workqueue: netns cleanup_net
[  226.541776] task: ffff8800371e0000 ti: ffff88003730c000 task.ti: ffff88003730c000
[  226.541776] RIP: 0010:[<ffffffff81389ba9>]  [<ffffffff81389ba9>] __list_del_entry+0x29/0xd0
[  226.541776] RSP: 0018:ffff88003730dbd0  EFLAGS: 00010a83
[  226.541776] RAX: 6b6b6b6b6b6b6b6b RBX: ffff8800374e6c40 RCX: dead000000200200
[  226.541776] RDX: 6b6b6b6b6b6b6b6b RSI: ffff8800371e07d0 RDI: ffff8800374e6c40
[  226.541776] RBP: ffff88003730dbd0 R08: 0000000000000000 R09: 0000000000000000
[  226.541776] R10: 0000000000000001 R11: ffff88003730d92e R12: 0000000000000002
[  226.541776] R13: ffff88007a4c42d0 R14: ffff88007aef0000 R15: ffff880036cf0018
[  226.541776] FS:  0000000000000000(0000) GS:ffff88007fc00000(0000) knlGS:0000000000000000
[  226.541776] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[  226.541776] CR2: 00007f07f643f7d0 CR3: 0000000036fd2000 CR4: 00000000000006f0
[  226.541776] Stack:
[  226.541776]  ffff88003730dbe8 ffffffff81389c5d ffff8800374ffbe4 ffff88003730dc28
[  226.541776]  ffffffffa0162a43 ffffffffa01627c5 ffff88007a4c42d0 ffff88007aef0000
[  226.541776]  ffffffffa01651c0 ffff88007a4c45e0 ffff88007aef0000 ffff88003730dc40
[  226.541776] Call Trace:
[  226.541776]  [<ffffffff81389c5d>] list_del+0xd/0x30
[  226.541776]  [<ffffffffa0162a43>] nf_ct_gre_keymap_destroy+0x283/0x2d0 [nf_conntrack_proto_gre]
[  226.541776]  [<ffffffffa01627c5>] ? nf_ct_gre_keymap_destroy+0x5/0x2d0 [nf_conntrack_proto_gre]
[  226.541776]  [<ffffffffa0162ab7>] gre_destroy+0x27/0x70 [nf_conntrack_proto_gre]
[  226.541776]  [<ffffffffa0117de3>] destroy_conntrack+0x83/0x200 [nf_conntrack]
[  226.541776]  [<ffffffffa0117d87>] ? destroy_conntrack+0x27/0x200 [nf_conntrack]
[  226.541776]  [<ffffffffa0117d60>] ? nf_conntrack_hash_check_insert+0x2e0/0x2e0 [nf_conntrack]
[  226.541776]  [<ffffffff81630142>] nf_conntrack_destroy+0x72/0x180
[  226.541776]  [<ffffffff816300d5>] ? nf_conntrack_destroy+0x5/0x180
[  226.541776]  [<ffffffffa011ef80>] ? kill_l3proto+0x20/0x20 [nf_conntrack]
[  226.541776]  [<ffffffffa011847e>] nf_ct_iterate_cleanup+0x14e/0x170 [nf_conntrack]
[  226.541776]  [<ffffffffa011f74b>] nf_ct_l4proto_pernet_unregister+0x5b/0x90 [nf_conntrack]
[  226.541776]  [<ffffffffa0162409>] proto_gre_net_exit+0x19/0x30 [nf_conntrack_proto_gre]
[  226.541776]  [<ffffffff815edf89>] ops_exit_list.isra.1+0x39/0x60
[  226.541776]  [<ffffffff815eecc0>] cleanup_net+0x100/0x1d0
[  226.541776]  [<ffffffff810a608a>] process_one_work+0x1ea/0x4f0
[  226.541776]  [<ffffffff810a6028>] ? process_one_work+0x188/0x4f0
[  226.541776]  [<ffffffff810a64ab>] worker_thread+0x11b/0x3a0
[  226.541776]  [<ffffffff810a6390>] ? process_one_work+0x4f0/0x4f0
[  226.541776]  [<ffffffff810af42d>] kthread+0xed/0x110
[  226.541776]  [<ffffffff8173d4dc>] ? _raw_spin_unlock_irq+0x2c/0x40
[  226.541776]  [<ffffffff810af340>] ? kthread_create_on_node+0x200/0x200
[  226.541776]  [<ffffffff8174747c>] ret_from_fork+0x7c/0xb0
[  226.541776]  [<ffffffff810af340>] ? kthread_create_on_node+0x200/0x200
[  226.541776] Code: 00 00 55 48 8b 17 48 b9 00 01 10 00 00 00 ad de
48 8b 47 08 48 89 e5 48 39 ca 74 29 48 b9 00 02 20 00 00 00 ad de 48
39 c8 74 7a <4c> 8b 00 4c 39 c7 75 53 4c 8b 42 08 4c 39 c7 75 2b 48 89
42 08
[  226.541776] RIP  [<ffffffff81389ba9>] __list_del_entry+0x29/0xd0
[  226.541776]  RSP <ffff88003730dbd0>
[  226.612193] ---[ end trace 985ae23ddfcc357c ]---

Cc: Pablo Neira Ayuso <[email protected]>
Cc: Patrick McHardy <[email protected]>
Cc: Jozsef Kadlecsik <[email protected]>
Cc: "David S. Miller" <[email protected]>
Signed-off-by: Andrey Vagin <[email protected]>
Signed-off-by: Pablo Neira Ayuso <[email protected]>
Puneeth-n pushed a commit to Puneeth-n/linux that referenced this pull request Apr 17, 2014
This patch uses of_node_init() to initialize the kobject in the fake
node used in test_of_node(), to avoid following kobject warning.

[    0.897654] kobject: '(null)' (c0000007ca183a08): is not initialized, yet kobject_put() is being called.
[    0.897682] ------------[ cut here ]------------
[    0.897688] WARNING: at lib/kobject.c:670
[    0.897692] Modules linked in:
[    0.897701] CPU: 4 PID: 1 Comm: swapper/0 Not tainted 3.14.0+ alexander-zimmermann#1
[    0.897708] task: c0000007ca100000 ti: c0000007ca180000 task.ti: c0000007ca180000
[    0.897715] NIP: c00000000046a1f0 LR: c00000000046a1ec CTR: 0000000001704660
[    0.897721] REGS: c0000007ca1835c0 TRAP: 0700   Not tainted  (3.14.0+)
[    0.897727] MSR: 8000000000029032 <SF,EE,ME,IR,DR,RI>  CR: 28000024  XER: 0000000d
[    0.897749] CFAR: c0000000008ef4ec SOFTE: 1
GPR00: c00000000046a1ec c0000007ca183840 c0000000014c59b8 000000000000005c
GPR04: 0000000000000001 c000000000129770 0000000000000000 0000000000000001
GPR08: 0000000000000000 0000000000000000 0000000000000000 0000000000003fef
GPR12: 0000000000000000 c00000000f221200 c00000000000c350 0000000000000000
GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
GPR20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
GPR24: 0000000000000000 c00000000144e808 c000000000c56f20 00000000000000d8
GPR28: c000000000cd5058 0000000000000000 c000000001454ca8 c0000007ca183a08
[    0.897856] NIP [c00000000046a1f0] .kobject_put+0xa0/0xb0
[    0.897863] LR [c00000000046a1ec] .kobject_put+0x9c/0xb0
[    0.897868] Call Trace:
[    0.897874] [c0000007ca183840] [c00000000046a1ec] .kobject_put+0x9c/0xb0 (unreliable)
[    0.897885] [c0000007ca1838c0] [c000000000743f9c] .of_node_put+0x2c/0x50
[    0.897894] [c0000007ca183940] [c000000000c83954] .test_of_node+0x1dc/0x208
[    0.897902] [c0000007ca183b80] [c000000000c839a4] .msi_bitmap_selftest+0x24/0x38
[    0.897913] [c0000007ca183bf0] [c00000000000bb34] .do_one_initcall+0x144/0x200
[    0.897922] [c0000007ca183ce0] [c000000000c748e4] .kernel_init_freeable+0x2b4/0x394
[    0.897931] [c0000007ca183db0] [c00000000000c374] .kernel_init+0x24/0x130
[    0.897940] [c0000007ca183e30] [c00000000000a2f4] .ret_from_kernel_thread+0x5c/0x68
[    0.897947] Instruction dump:
[    0.897952] 7fe3fb78 38210080 e8010010 ebe1fff8 7c0803a6 4800014c e89f0000 3c62ff6e
[    0.897971] 7fe5fb78 3863a950 48485279 60000000 <0fe00000> 39000000 393f0038 4bffff80
[    0.897992] ---[ end trace 1eeffdb9f825a556 ]---

Signed-off-by: Li Zhong <[email protected]>
Signed-off-by: Benjamin Herrenschmidt <[email protected]>
Puneeth-n pushed a commit to Puneeth-n/linux that referenced this pull request Apr 17, 2014
…thing to be update

Since v1:
	Edited the comment according to Srivatsa's suggestion.

During the testing, we encounter below WARN followed by Oops:

	WARNING: at kernel/sched/core.c:6218
	...
	NIP [c000000000101660] .build_sched_domains+0x11d0/0x1200
	LR [c000000000101358] .build_sched_domains+0xec8/0x1200
	PACATMSCRATCH [800000000000f032]
	Call Trace:
	[c00000001b103850] [c000000000101358] .build_sched_domains+0xec8/0x1200
	[c00000001b1039a0] [c00000000010aad4] .partition_sched_domains+0x484/0x510
	[c00000001b103aa0] [c00000000016d0a8] .rebuild_sched_domains+0x68/0xa0
	[c00000001b103b30] [c00000000005cbf0] .topology_work_fn+0x10/0x30
	...
	Oops: Kernel access of bad area, sig: 11 [alexander-zimmermann#1]
	...
	NIP [c00000000045c000] .__bitmap_weight+0x60/0xf0
	LR [c00000000010132c] .build_sched_domains+0xe9c/0x1200
	PACATMSCRATCH [8000000000029032]
	Call Trace:
	[c00000001b1037a0] [c000000000288ff4] .kmem_cache_alloc_node_trace+0x184/0x3a0
	[c00000001b103850] [c00000000010132c] .build_sched_domains+0xe9c/0x1200
	[c00000001b1039a0] [c00000000010aad4] .partition_sched_domains+0x484/0x510
	[c00000001b103aa0] [c00000000016d0a8] .rebuild_sched_domains+0x68/0xa0
	[c00000001b103b30] [c00000000005cbf0] .topology_work_fn+0x10/0x30
	...

This was caused by that 'sd->groups == NULL' after building groups, which
was caused by the empty 'sd->span'.

The cpu's domain contained nothing because the cpu was assigned to a wrong
node, due to the following unfortunate sequence of events:

1. The hypervisor sent a topology update to the guest OS, to notify changes
   to the cpu-node mapping. However, the update was actually redundant - i.e.,
   the "new" mapping was exactly the same as the old one.

2. Due to this, the 'updated_cpus' mask turned out to be empty after exiting
   the 'for-loop' in arch_update_cpu_topology().

3. So we ended up calling stop-machine() with an empty cpumask list, which made
   stop-machine internally elect cpumask_first(cpu_online_mask), i.e., CPU0 as
   the cpu to run the payload (the update_cpu_topology() function).

4. This causes update_cpu_topology() to be run by CPU0. And since 'updates'
   is kzalloc()'ed inside arch_update_cpu_topology(), update_cpu_topology()
   finds update->cpu as well as update->new_nid to be 0. In other words, we
   end up assigning CPU0 (and eventually its siblings) to node 0, incorrectly.

Along with the following wrong updating, it causes the sched-domain rebuild
code to break and crash the system.

Fix this by skipping the topology update in cases where we find that
the topology has not actually changed in reality (ie., spurious updates).

CC: Benjamin Herrenschmidt <[email protected]>
CC: Paul Mackerras <[email protected]>
CC: Nathan Fontenot <[email protected]>
CC: Stephen Rothwell <[email protected]>
CC: Andrew Morton <[email protected]>
CC: Robert Jennings <[email protected]>
CC: Jesse Larrew <[email protected]>
CC: "Srivatsa S. Bhat" <[email protected]>
CC: Alistair Popple <[email protected]>
Suggested-by: "Srivatsa S. Bhat" <[email protected]>
Signed-off-by: Michael Wang <[email protected]>
Reviewed-by: Srivatsa S. Bhat <[email protected]>
Signed-off-by: Benjamin Herrenschmidt <[email protected]>
Puneeth-n pushed a commit to Puneeth-n/linux that referenced this pull request Apr 17, 2014
Martin reported that his test system would not boot with
current git, it oopsed with this:

BUG: unable to handle kernel paging request at ffff88046c6c9e80
IP: [<ffffffff812971e0>] blk_queue_start_tag+0x90/0x150
PGD 1ddf067 PUD 1de2067 PMD 47fc7d067 PTE 800000046c6c9060
Oops: 0002 [alexander-zimmermann#1] SMP DEBUG_PAGEALLOC
Modules linked in: sd_mod lpfc(+) scsi_transport_fc scsi_tgt oracleasm
rpcsec_gss_krb5 ipv6 igb dca i2c_algo_bit i2c_core hwmon
CPU: 3 PID: 87 Comm: kworker/u17:1 Not tainted 3.14.0+ torvalds#246
Hardware name: Supermicro X9DRX+-F/X9DRX+-F, BIOS 3.00 07/09/2013
Workqueue: events_unbound async_run_entry_fn
task: ffff8802743c2150 ti: ffff880273d02000 task.ti: ffff880273d02000
RIP: 0010:[<ffffffff812971e0>]  [<ffffffff812971e0>]
blk_queue_start_tag+0x90/0x150
RSP: 0018:ffff880273d03a58  EFLAGS: 00010092
RAX: ffff88046c6c9e78 RBX: ffff880077208e78 RCX: 00000000fffc8da6
RDX: 00000000fffc186d RSI: 0000000000000009 RDI: 00000000fffc8d9d
RBP: ffff880273d03a88 R08: 0000000000000001 R09: ffff8800021c2410
R10: 0000000000000005 R11: 0000000000015b30 R12: ffff88046c5bb8a0
R13: ffff88046c5c0890 R14: 000000000000001e R15: 000000000000001e
FS:  0000000000000000(0000) GS:ffff880277b00000(0000)
knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff88046c6c9e80 CR3: 00000000018f6000 CR4: 00000000000407e0
Stack:
 ffff880273d03a98 ffff880474b18800 0000000000000000 ffff880474157000
 ffff88046c5c0890 ffff880077208e78 ffff880273d03ae8 ffffffff813b9e62
 ffff880200000010 ffff880474b18968 ffff880474b18848 ffff88046c5c0cd8
Call Trace:
 [<ffffffff813b9e62>] scsi_request_fn+0xf2/0x510
 [<ffffffff81293167>] __blk_run_queue+0x37/0x50
 [<ffffffff8129ac43>] blk_execute_rq_nowait+0xb3/0x130
 [<ffffffff8129ad24>] blk_execute_rq+0x64/0xf0
 [<ffffffff8108d2b0>] ? bit_waitqueue+0xd0/0xd0
 [<ffffffff813bba35>] scsi_execute+0xe5/0x180
 [<ffffffff813bbe4a>] scsi_execute_req_flags+0x9a/0x110
 [<ffffffffa01b1304>] sd_spinup_disk+0x94/0x460 [sd_mod]
 [<ffffffff81160000>] ? __unmap_hugepage_range+0x200/0x2f0
 [<ffffffffa01b2b9a>] sd_revalidate_disk+0xaa/0x3f0 [sd_mod]
 [<ffffffffa01b2fb8>] sd_probe_async+0xd8/0x200 [sd_mod]
 [<ffffffff8107703f>] async_run_entry_fn+0x3f/0x140
 [<ffffffff8106a1c5>] process_one_work+0x175/0x410
 [<ffffffff8106b373>] worker_thread+0x123/0x400
 [<ffffffff8106b250>] ? manage_workers+0x160/0x160
 [<ffffffff8107104e>] kthread+0xce/0xf0
 [<ffffffff81070f80>] ? kthread_freezable_should_stop+0x70/0x70
 [<ffffffff815f0bac>] ret_from_fork+0x7c/0xb0
 [<ffffffff81070f80>] ? kthread_freezable_should_stop+0x70/0x70
Code: 48 0f ab 11 72 db 48 81 4b 40 00 00 10 00 89 83 08 01 00 00 48 89
df 49 8b 04 24 48 89 1c d0 e8 f7 a8 ff ff 49 8b 85 28 05 00 00 <48> 89
58 08 48 89 03 49 8d 85 28 05 00 00 48 89 43 08 49 89 9d
RIP  [<ffffffff812971e0>] blk_queue_start_tag+0x90/0x150
 RSP <ffff880273d03a58>
CR2: ffff88046c6c9e80

Martin bisected and found this to be the problem patch;

	commit 6d11339
	Author: Jan Kara <[email protected]>
	Date:   Mon Feb 24 16:39:54 2014 +0100

	    block: Stop abusing rq->csd.list in blk-softirq

and the problem was immediately apparent. The patch states that
it is safe to reuse queuelist at completion time, since it is
no longer used. However, that is not true if a device is using
block enabled tagging. If that is the case, then the queuelist
is reused to keep track of busy tags. If a device also ended
up using softirq completions, we'd reuse ->queuelist for the
IPI handling while block tagging was still using it. Boom.

Fix this by adding a new ipi_list list head, and share the
memory used with the request hash table. The hash table is
never used after the request is moved to the dispatch list,
which happens long before any potential completion of the
request. Add a new request bit for this, so we don't have
cases that check rq->hash while it could potentially have
been reused for the IPI completion.

Reported-by: Martin K. Petersen <[email protected]>
Tested-by: Benjamin Herrenschmidt <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
Puneeth-n pushed a commit to Puneeth-n/linux that referenced this pull request Apr 17, 2014
…f the receiver's buffer"

This reverts commit ef2820a ("net: sctp: Fix a_rwnd/rwnd management
to reflect real state of the receiver's buffer") as it introduced a
serious performance regression on SCTP over IPv4 and IPv6, though a not
as dramatic on the latter. Measurements are on 10Gbit/s with ixgbe NICs.

Current state:

[root@Lab200slot2 ~]# iperf3 --sctp -4 -c 192.168.241.3 -V -l 1452 -t 60
iperf version 3.0.1 (10 January 2014)
Linux Lab200slot2 3.14.0 alexander-zimmermann#1 SMP Thu Apr 3 23:18:29 EDT 2014 x86_64
Time: Fri, 11 Apr 2014 17:56:21 GMT
Connecting to host 192.168.241.3, port 5201
      Cookie: Lab200slot2.1397238981.812898.548918
[  4] local 192.168.241.2 port 38616 connected to 192.168.241.3 port 5201
Starting Test: protocol: SCTP, 1 streams, 1452 byte blocks, omitting 0 seconds, 60 second test
[ ID] Interval           Transfer     Bandwidth
[  4]   0.00-1.09   sec  20.8 MBytes   161 Mbits/sec
[  4]   1.09-2.13   sec  10.8 MBytes  86.8 Mbits/sec
[  4]   2.13-3.15   sec  3.57 MBytes  29.5 Mbits/sec
[  4]   3.15-4.16   sec  4.33 MBytes  35.7 Mbits/sec
[  4]   4.16-6.21   sec  10.4 MBytes  42.7 Mbits/sec
[  4]   6.21-6.21   sec  0.00 Bytes    0.00 bits/sec
[  4]   6.21-7.35   sec  34.6 MBytes   253 Mbits/sec
[  4]   7.35-11.45  sec  22.0 MBytes  45.0 Mbits/sec
[  4]  11.45-11.45  sec  0.00 Bytes    0.00 bits/sec
[  4]  11.45-11.45  sec  0.00 Bytes    0.00 bits/sec
[  4]  11.45-11.45  sec  0.00 Bytes    0.00 bits/sec
[  4]  11.45-12.51  sec  16.0 MBytes   126 Mbits/sec
[  4]  12.51-13.59  sec  20.3 MBytes   158 Mbits/sec
[  4]  13.59-14.65  sec  13.4 MBytes   107 Mbits/sec
[  4]  14.65-16.79  sec  33.3 MBytes   130 Mbits/sec
[  4]  16.79-16.79  sec  0.00 Bytes    0.00 bits/sec
[  4]  16.79-17.82  sec  5.94 MBytes  48.7 Mbits/sec
(etc)

[root@Lab200slot2 ~]#  iperf3 --sctp -6 -c 2001:db8:0:f101::1 -V -l 1400 -t 60
iperf version 3.0.1 (10 January 2014)
Linux Lab200slot2 3.14.0 alexander-zimmermann#1 SMP Thu Apr 3 23:18:29 EDT 2014 x86_64
Time: Fri, 11 Apr 2014 19:08:41 GMT
Connecting to host 2001:db8:0:f101::1, port 5201
      Cookie: Lab200slot2.1397243321.714295.2b3f7c
[  4] local 2001:db8:0:f101::2 port 55804 connected to 2001:db8:0:f101::1 port 5201
Starting Test: protocol: SCTP, 1 streams, 1400 byte blocks, omitting 0 seconds, 60 second test
[ ID] Interval           Transfer     Bandwidth
[  4]   0.00-1.00   sec   169 MBytes  1.42 Gbits/sec
[  4]   1.00-2.00   sec   201 MBytes  1.69 Gbits/sec
[  4]   2.00-3.00   sec   188 MBytes  1.58 Gbits/sec
[  4]   3.00-4.00   sec   174 MBytes  1.46 Gbits/sec
[  4]   4.00-5.00   sec   165 MBytes  1.39 Gbits/sec
[  4]   5.00-6.00   sec   199 MBytes  1.67 Gbits/sec
[  4]   6.00-7.00   sec   163 MBytes  1.36 Gbits/sec
[  4]   7.00-8.00   sec   174 MBytes  1.46 Gbits/sec
[  4]   8.00-9.00   sec   193 MBytes  1.62 Gbits/sec
[  4]   9.00-10.00  sec   196 MBytes  1.65 Gbits/sec
[  4]  10.00-11.00  sec   157 MBytes  1.31 Gbits/sec
[  4]  11.00-12.00  sec   175 MBytes  1.47 Gbits/sec
[  4]  12.00-13.00  sec   192 MBytes  1.61 Gbits/sec
[  4]  13.00-14.00  sec   199 MBytes  1.67 Gbits/sec
(etc)

After patch:

[root@Lab200slot2 ~]#  iperf3 --sctp -4 -c 192.168.240.3 -V -l 1452 -t 60
iperf version 3.0.1 (10 January 2014)
Linux Lab200slot2 3.14.0+ alexander-zimmermann#1 SMP Mon Apr 14 12:06:40 EDT 2014 x86_64
Time: Mon, 14 Apr 2014 16:40:48 GMT
Connecting to host 192.168.240.3, port 5201
      Cookie: Lab200slot2.1397493648.413274.65e131
[  4] local 192.168.240.2 port 50548 connected to 192.168.240.3 port 5201
Starting Test: protocol: SCTP, 1 streams, 1452 byte blocks, omitting 0 seconds, 60 second test
[ ID] Interval           Transfer     Bandwidth
[  4]   0.00-1.00   sec   240 MBytes  2.02 Gbits/sec
[  4]   1.00-2.00   sec   239 MBytes  2.01 Gbits/sec
[  4]   2.00-3.00   sec   240 MBytes  2.01 Gbits/sec
[  4]   3.00-4.00   sec   239 MBytes  2.00 Gbits/sec
[  4]   4.00-5.00   sec   245 MBytes  2.05 Gbits/sec
[  4]   5.00-6.00   sec   240 MBytes  2.01 Gbits/sec
[  4]   6.00-7.00   sec   240 MBytes  2.02 Gbits/sec
[  4]   7.00-8.00   sec   239 MBytes  2.01 Gbits/sec

With the reverted patch applied, the SCTP/IPv4 performance is back
to normal on latest upstream for IPv4 and IPv6 and has same throughput
as 3.4.2 test kernel, steady and interval reports are smooth again.

Fixes: ef2820a ("net: sctp: Fix a_rwnd/rwnd management to reflect real state of the receiver's buffer")
Reported-by: Peter Butler <[email protected]>
Reported-by: Dongsheng Song <[email protected]>
Reported-by: Fengguang Wu <[email protected]>
Tested-by: Peter Butler <[email protected]>
Signed-off-by: Daniel Borkmann <[email protected]>
Cc: Matija Glavinic Pecotic <[email protected]>
Cc: Alexander Sverdlin <[email protected]>
Cc: Vlad Yasevich <[email protected]>
Acked-by: Vlad Yasevich <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Puneeth-n pushed a commit to Puneeth-n/linux that referenced this pull request Apr 23, 2014
With EXT4FS_DEBUG ext4_count_free_clusters() will call
ext4_read_block_bitmap() without s_group_info initialized, so we need to
initialize multi-block allocator before.

And dependencies that must be solved, to allow this:
- multi-block allocator needs in group descriptors
- need to install s_op before initializing multi-block allocator,
  because in ext4_mb_init_backend() new inode is created.
- initialize number of group desc blocks (s_gdb_count) otherwise
  number of clusters returned by ext4_free_clusters_after_init() is not correct.
  (see ext4_bg_num_gdb_nometa())

Here is the stack backtrace:

(gdb) bt
 #0  ext4_get_group_info (group=0, sb=0xffff880079a10000) at ext4.h:2430
 alexander-zimmermann#1  ext4_validate_block_bitmap (sb=sb@entry=0xffff880079a10000,
     desc=desc@entry=0xffff880056510000, block_group=block_group@entry=0,
     bh=bh@entry=0xffff88007bf2b2d8) at balloc.c:358
 #2  0xffffffff81232202 in ext4_wait_block_bitmap (sb=sb@entry=0xffff880079a10000,
     block_group=block_group@entry=0,
     bh=bh@entry=0xffff88007bf2b2d8) at balloc.c:476
 #3  0xffffffff81232eaf in ext4_read_block_bitmap (sb=sb@entry=0xffff880079a10000,
     block_group=block_group@entry=0) at balloc.c:489
 #4  0xffffffff81232fc0 in ext4_count_free_clusters (sb=sb@entry=0xffff880079a10000) at balloc.c:665
 #5  0xffffffff81259ffa in ext4_check_descriptors (first_not_zeroed=<synthetic pointer>,
     sb=0xffff880079a10000) at super.c:2143
 torvalds#6  ext4_fill_super (sb=sb@entry=0xffff880079a10000, data=<optimized out>,
     data@entry=0x0 <irq_stack_union>, silent=silent@entry=0) at super.c:3851
     ...

Signed-off-by: Azat Khuzhin <[email protected]>
Signed-off-by: "Theodore Ts'o" <[email protected]>
Puneeth-n pushed a commit to Puneeth-n/linux that referenced this pull request Apr 23, 2014
When heavily exercising xattr code the assertion that
jbd2_journal_dirty_metadata() shouldn't return error was triggered:

WARNING: at /srv/autobuild-ceph/gitbuilder.git/build/fs/jbd2/transaction.c:1237
jbd2_journal_dirty_metadata+0x1ba/0x260()

CPU: 0 PID: 8877 Comm: ceph-osd Tainted: G    W 3.10.0-ceph-00049-g68d04c9 alexander-zimmermann#1
Hardware name: Dell Inc. PowerEdge R410/01V648, BIOS 1.6.3 02/07/2011
 ffffffff81a1d3c8 ffff880214469928 ffffffff816311b0 ffff880214469968
 ffffffff8103fae0 ffff880214469958 ffff880170a9dc30 ffff8802240fbe80
 0000000000000000 ffff88020b366000 ffff8802256e7510 ffff880214469978
Call Trace:
 [<ffffffff816311b0>] dump_stack+0x19/0x1b
 [<ffffffff8103fae0>] warn_slowpath_common+0x70/0xa0
 [<ffffffff8103fb2a>] warn_slowpath_null+0x1a/0x20
 [<ffffffff81267c2a>] jbd2_journal_dirty_metadata+0x1ba/0x260
 [<ffffffff81245093>] __ext4_handle_dirty_metadata+0xa3/0x140
 [<ffffffff812561f3>] ext4_xattr_release_block+0x103/0x1f0
 [<ffffffff81256680>] ext4_xattr_block_set+0x1e0/0x910
 [<ffffffff8125795b>] ext4_xattr_set_handle+0x38b/0x4a0
 [<ffffffff810a319d>] ? trace_hardirqs_on+0xd/0x10
 [<ffffffff81257b32>] ext4_xattr_set+0xc2/0x140
 [<ffffffff81258547>] ext4_xattr_user_set+0x47/0x50
 [<ffffffff811935ce>] generic_setxattr+0x6e/0x90
 [<ffffffff81193ecb>] __vfs_setxattr_noperm+0x7b/0x1c0
 [<ffffffff811940d4>] vfs_setxattr+0xc4/0xd0
 [<ffffffff8119421e>] setxattr+0x13e/0x1e0
 [<ffffffff811719c7>] ? __sb_start_write+0xe7/0x1b0
 [<ffffffff8118f2e8>] ? mnt_want_write_file+0x28/0x60
 [<ffffffff8118c65c>] ? fget_light+0x3c/0x130
 [<ffffffff8118f2e8>] ? mnt_want_write_file+0x28/0x60
 [<ffffffff8118f1f8>] ? __mnt_want_write+0x58/0x70
 [<ffffffff811946be>] SyS_fsetxattr+0xbe/0x100
 [<ffffffff816407c2>] system_call_fastpath+0x16/0x1b

The reason for the warning is that buffer_head passed into
jbd2_journal_dirty_metadata() didn't have journal_head attached. This is
caused by the following race of two ext4_xattr_release_block() calls:

CPU1                                CPU2
ext4_xattr_release_block()          ext4_xattr_release_block()
lock_buffer(bh);
/* False */
if (BHDR(bh)->h_refcount == cpu_to_le32(1))
} else {
  le32_add_cpu(&BHDR(bh)->h_refcount, -1);
  unlock_buffer(bh);
                                    lock_buffer(bh);
                                    /* True */
                                    if (BHDR(bh)->h_refcount == cpu_to_le32(1))
                                      get_bh(bh);
                                      ext4_free_blocks()
                                        ...
                                        jbd2_journal_forget()
                                          jbd2_journal_unfile_buffer()
                                          -> JH is gone
  error = ext4_handle_dirty_xattr_block(handle, inode, bh);
  -> triggers the warning

We fix the problem by moving ext4_handle_dirty_xattr_block() under the
buffer lock. Sadly this cannot be done in nojournal mode as that
function can call sync_dirty_buffer() which would deadlock. Luckily in
nojournal mode the race is harmless (we only dirty already freed buffer)
and thus for nojournal mode we leave the dirtying outside of the buffer
lock.

Reported-by: Sage Weil <[email protected]>
Signed-off-by: Jan Kara <[email protected]>
Signed-off-by: "Theodore Ts'o" <[email protected]>
Cc: [email protected]
Puneeth-n pushed a commit to Puneeth-n/linux that referenced this pull request Apr 23, 2014
The function ext4_update_i_disksize() is used in only one place, in
the function mpage_map_and_submit_extent().  Move its code to simplify
the code paths, and also move the call to ext4_mark_inode_dirty() into
the i_data_sem's critical region, to be consistent with all of the
other places where we update i_disksize.  That way, we also keep the
raw_inode's i_disksize protected, to avoid the following race:

      CPU alexander-zimmermann#1                                 CPU #2

   down_write(&i_data_sem)
   Modify i_disk_size
   up_write(&i_data_sem)
                                        down_write(&i_data_sem)
                                        Modify i_disk_size
                                        Copy i_disk_size to on-disk inode
                                        up_write(&i_data_sem)
   Copy i_disk_size to on-disk inode

Signed-off-by: "Theodore Ts'o" <[email protected]>
Reviewed-by: Jan Kara <[email protected]>
Cc: [email protected]
Puneeth-n pushed a commit to Puneeth-n/linux that referenced this pull request Apr 23, 2014
There is a race when moving a QP from RTS->CLOSING where a SQ work
request could be posted after the FW receives the RDMA_RI/FINI WR.
The SQ work request will never get processed, and should be completed
with FLUSHED status.  Function c4iw_flush_sq(), however was dropping
the oldest SQ work request when in CLOSING or IDLE states, instead of
completing the pending work request. If that oldest pending work
request was actually complete and has a CQE in the CQ, then when that
CQE is proceessed in poll_cq, we'll BUG_ON() due to the inconsistent
SQ/CQ state.

This is a very small timing hole and has only been hit once so far.

The fix is two-fold:

1) c4iw_flush_sq() MUST always flush all non-completed WRs with FLUSHED
   status regardless of the QP state.

2) In c4iw_modify_rc_qp(), always set the "in error" bit on the queue
   before moving the state out of RTS.  This ensures that the state
   transition will not happen while another thread is in
   post_rc_send(), because set_state() and post_rc_send() both aquire
   the qp spinlock.  Also, once we transition the state out of RTS,
   subsequent calls to post_rc_send() will fail because the "in error"
   bit is set.  I don't think this fully closes the race where the FW
   can get a FINI followed a SQ work request being posted (because
   they are posted to differente EQs), but the alexander-zimmermann#1 fix will handle the
   issue by flushing the SQ work request.

Signed-off-by: Steve Wise <[email protected]>
Signed-off-by: Roland Dreier <[email protected]>
Puneeth-n pushed a commit to Puneeth-n/linux that referenced this pull request Apr 23, 2014
Commit aa92b6f (gpio / ACPI: Allocate ACPI specific data directly in
acpi_gpiochip_add()) moved ACPI handle checking to acpi_gpiochip_add() but
forgot to check whether chip->dev is NULL before dereferencing it.

Since chip->dev pointer is optional we can end up with crash like following:

 BUG: unable to handle kernel NULL pointer dereference at 00000138
 IP: [<c126c2b3>] acpi_gpiochip_add+0x13/0x190
 *pde = 00000000
 Oops: 0000 [alexander-zimmermann#1] PREEMPT SMP
 Modules linked in: ssb(+) ...
 CPU: 0 PID: 512 Comm: modprobe Tainted: G        W     3.14.0-rc7-next-20140324-t1 torvalds#24
 Hardware name: Dell Inc. Latitude D830                   /0UY141, BIOS A02 06/07/2007
 task: f5799900 ti: f543e000 task.ti: f543e000
 EIP: 0060:[<c126c2b3>] EFLAGS: 00010282 CPU: 0
 EIP is at acpi_gpiochip_add+0x13/0x190
 EAX: 00000000 EBX: f57824c4 ECX: 00000000 EDX: 00000000
 ESI: f57824c4 EDI: 00000010 EBP: f543fc54 ESP: f543fc40
  DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068
 CR0: 8005003b CR2: 00000138 CR3: 355f8000 CR4: 000007d0
 Stack:
  f543fc5c fd1f7790 f57824c4 000000be 00000010 f543fc84 c1269f4e f543fc74
  fd1f78bd 00008002 f57822b0 f5782090 fd1f8400 00000286 fd1f9994 00000000
  f5782000 f543fc8c fd1f7e39 f543fcc8 fd1f0bd8 000000c0 00000000 00000000
 Call Trace:
  [<fd1f7790>] ? ssb_pcie_mdio_write+0xa0/0xd0 [ssb]
  [<c1269f4e>] gpiochip_add+0xee/0x300
  [<fd1f78bd>] ? ssb_pcicore_serdes_workaround+0xfd/0x140 [ssb]
  [<fd1f7e39>] ssb_gpio_init+0x89/0xa0 [ssb]
  [<fd1f0bd8>] ssb_attach_queued_buses+0xc8/0x2d0 [ssb]
  [<fd1f0f65>] ssb_bus_register+0x185/0x1f0 [ssb]
  [<fd1f3120>] ? ssb_pci_xtal+0x220/0x220 [ssb]
  [<fd1f106c>] ssb_bus_pcibus_register+0x2c/0x80 [ssb]
  [<fd1f40dc>] ssb_pcihost_probe+0x9c/0x110 [ssb]
  [<c1276c8f>] pci_device_probe+0x6f/0xc0
  [<c11bdb55>] ? sysfs_create_link+0x25/0x40
  [<c131d8b9>] driver_probe_device+0x79/0x360
  [<c1276512>] ? pci_match_device+0xb2/0xc0
  [<c131dc51>] __driver_attach+0x71/0x80
  [<c131dbe0>] ? __device_attach+0x40/0x40
  [<c131bd87>] bus_for_each_dev+0x47/0x80
  [<c131d3ae>] driver_attach+0x1e/0x20
  [<c131dbe0>] ? __device_attach+0x40/0x40
  [<c131d007>] bus_add_driver+0x157/0x230
  [<c131e219>] driver_register+0x59/0xe0
  ...

Fix this by checking chip->dev pointer against NULL first. Also we can now
remove redundant check in acpi_gpiochip_request/free_interrupts().

Reported-by: Sabrina Dubroca <[email protected]>
Signed-off-by: Mika Westerberg <[email protected]>
Tested-by: Sabrina Dubroca <[email protected]>
Acked-by: Alexandre Courbot <[email protected]>
Tested-by: Josh Boyer <[email protected]>
Signed-off-by: Linus Walleij <[email protected]>
Puneeth-n pushed a commit to Puneeth-n/linux that referenced this pull request Apr 23, 2014
…ersal

3bc9559 ("powerpc/PCI: Use list_for_each_entry() for bus traversal")
caused a NULL pointer dereference because the loop body set the iterator to
NULL:

  Unable to handle kernel paging request for data at address 0x00000000
  Faulting instruction address: 0xc000000000041d78
  Oops: Kernel access of bad area, sig: 11 [alexander-zimmermann#1]
  ...
  NIP [c000000000041d78] .sys_pciconfig_iobase+0x68/0x1f0
  LR [c000000000041e0c] .sys_pciconfig_iobase+0xfc/0x1f0
  Call Trace:
  [c0000003b4787db0] [c000000000041e0c] .sys_pciconfig_iobase+0xfc/0x1f0 (unreliable)
  [c0000003b4787e30] [c000000000009ed8] syscall_exit+0x0/0x98

Fix it by using a temporary variable for the iterator.

[bhelgaas: changelog, drop tmp_bus initialization]
Fixes: 3bc9559 powerpc/PCI: Use list_for_each_entry() for bus traversal
Signed-off-by: Mike Qiu <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Puneeth-n pushed a commit to Puneeth-n/linux that referenced this pull request Apr 23, 2014
…nabled

With bigalloc enabled we must use EXT4_CLUSTERS_PER_GROUP() instead of
EXT4_BLOCKS_PER_GROUP() otherwise we will go beyond the allocated buffer.

$ mount -t ext4 /dev/vde /vde
[   70.573993] EXT4-fs DEBUG (fs/ext4/mballoc.c, 2346): ext4_mb_alloc_groupinfo:
[   70.575174] allocated s_groupinfo array for 1 meta_bg's
[   70.576172] EXT4-fs DEBUG (fs/ext4/super.c, 2092): ext4_check_descriptors:
[   70.576972] Checking group descriptorsBUG: unable to handle kernel paging request at ffff88006ab56000
[   72.463686] IP: [<ffffffff81394eb9>] __bitmap_weight+0x2a/0x7f
[   72.464168] PGD 295e067 PUD 2961067 PMD 7fa8e067 PTE 800000006ab56060
[   72.464738] Oops: 0000 [alexander-zimmermann#1] SMP DEBUG_PAGEALLOC
[   72.465139] Modules linked in:
[   72.465402] CPU: 1 PID: 3560 Comm: mount Tainted: G        W    3.14.0-rc2-00069-ge57bce1 torvalds#60
[   72.466079] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   72.466505] task: ffff88007ce6c8a0 ti: ffff88006b7f0000 task.ti: ffff88006b7f0000
[   72.466505] RIP: 0010:[<ffffffff81394eb9>]  [<ffffffff81394eb9>] __bitmap_weight+0x2a/0x7f
[   72.466505] RSP: 0018:ffff88006b7f1c00  EFLAGS: 00010206
[   72.466505] RAX: 0000000000000000 RBX: 000000000000050a RCX: 0000000000000040
[   72.466505] RDX: 0000000000000000 RSI: 0000000000080000 RDI: 0000000000000000
[   72.466505] RBP: ffff88006b7f1c28 R08: 0000000000000002 R09: 0000000000000000
[   72.466505] R10: 000000000000babe R11: 0000000000000400 R12: 0000000000080000
[   72.466505] R13: 0000000000000200 R14: 0000000000002000 R15: ffff88006ab55000
[   72.466505] FS:  00007f43ba1fa840(0000) GS:ffff88007f800000(0000) knlGS:0000000000000000
[   72.466505] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[   72.466505] CR2: ffff88006ab56000 CR3: 000000006b7e6000 CR4: 00000000000006e0
[   72.466505] Stack:
[   72.466505]  ffff88006ab65000 0000000000000000 0000000000000000 0000000000010000
[   72.466505]  ffff88006ab6f400 ffff88006b7f1c58 ffffffff81396bb8 0000000000010000
[   72.466505]  0000000000000000 ffff88007b869a90 ffff88006a48a000 ffff88006b7f1c70
[   72.466505] Call Trace:
[   72.466505]  [<ffffffff81396bb8>] memweight+0x5f/0x8a
[   72.466505]  [<ffffffff811c3b19>] ext4_count_free+0x13/0x21
[   72.466505]  [<ffffffff811c396c>] ext4_count_free_clusters+0xdb/0x171
[   72.466505]  [<ffffffff811e3bdd>] ext4_fill_super+0x117c/0x28ef
[   72.466505]  [<ffffffff81391569>] ? vsnprintf+0x1c7/0x3f7
[   72.466505]  [<ffffffff8114d8dc>] mount_bdev+0x145/0x19c
[   72.466505]  [<ffffffff811e2a61>] ? ext4_calculate_overhead+0x2a1/0x2a1
[   72.466505]  [<ffffffff811dab1d>] ext4_mount+0x15/0x17
[   72.466505]  [<ffffffff8114e3aa>] mount_fs+0x67/0x150
[   72.466505]  [<ffffffff811637ea>] vfs_kern_mount+0x64/0xde
[   72.466505]  [<ffffffff81165d19>] do_mount+0x6fe/0x7f5
[   72.466505]  [<ffffffff81126cc8>] ? strndup_user+0x3a/0xd9
[   72.466505]  [<ffffffff8116604b>] SyS_mount+0x85/0xbe
[   72.466505]  [<ffffffff81619e90>] tracesys+0xdd/0xe2
[   72.466505] Code: c3 89 f0 b9 40 00 00 00 55 99 48 89 e5 41 57 f7 f9 41 56 49 89 ff 41 55 45 31 ed 41 54 41 89 f4 53 31 db 41 89 c6 45 39 ee 7e 10 <4b> 8b 3c ef 49 ff c5 e8 bf ff ff ff 01 c3 eb eb 31 c0 45 85 f6
[   72.466505] RIP  [<ffffffff81394eb9>] __bitmap_weight+0x2a/0x7f
[   72.466505]  RSP <ffff88006b7f1c00>
[   72.466505] CR2: ffff88006ab56000
[   72.466505] ---[ end trace 7d051a08ae138573 ]---
Killed

Signed-off-by: "Theodore Ts'o" <[email protected]>
Puneeth-n pushed a commit to Puneeth-n/linux that referenced this pull request Apr 23, 2014
Mmapping a comedi data buffer with lockdep checking enabled produced the
following kernel debug messages:

======================================================
[ INFO: possible circular locking dependency detected ]
3.5.0-rc3-ija1+ torvalds#9 Tainted: G         C
-------------------------------------------------------
comedi_test/4160 is trying to acquire lock:
 (&dev->mutex#2){+.+.+.}, at: [<ffffffffa00313f4>] comedi_mmap+0x57/0x1d9 [comedi]

but task is already holding lock:
 (&mm->mmap_sem){++++++}, at: [<ffffffff810c96fe>] vm_mmap_pgoff+0x41/0x76

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> alexander-zimmermann#1 (&mm->mmap_sem){++++++}:
       [<ffffffff8106d0e8>] lock_acquire+0x97/0x105
       [<ffffffff810ce3bc>] might_fault+0x6d/0x90
       [<ffffffffa0031ffb>] do_devinfo_ioctl.isra.7+0x11e/0x14c [comedi]
       [<ffffffffa003227f>] comedi_unlocked_ioctl+0x256/0xe48 [comedi]
       [<ffffffff810f7fcd>] vfs_ioctl+0x18/0x34
       [<ffffffff810f87fd>] do_vfs_ioctl+0x382/0x43c
       [<ffffffff810f88f9>] sys_ioctl+0x42/0x65
       [<ffffffff81415c62>] system_call_fastpath+0x16/0x1b

-> #0 (&dev->mutex#2){+.+.+.}:
       [<ffffffff8106c528>] __lock_acquire+0x101d/0x1591
       [<ffffffff8106d0e8>] lock_acquire+0x97/0x105
       [<ffffffff8140c894>] mutex_lock_nested+0x46/0x2a4
       [<ffffffffa00313f4>] comedi_mmap+0x57/0x1d9 [comedi]
       [<ffffffff810d5816>] mmap_region+0x281/0x492
       [<ffffffff810d5c92>] do_mmap_pgoff+0x26b/0x2a7
       [<ffffffff810c971a>] vm_mmap_pgoff+0x5d/0x76
       [<ffffffff810d493f>] sys_mmap_pgoff+0xc7/0x10d
       [<ffffffff81004d36>] sys_mmap+0x16/0x20
       [<ffffffff81415c62>] system_call_fastpath+0x16/0x1b

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&mm->mmap_sem);
                               lock(&dev->mutex#2);
                               lock(&mm->mmap_sem);
  lock(&dev->mutex#2);

 *** DEADLOCK ***

To avoid the circular dependency, just try to get the lock in
`comedi_mmap()` instead of blocking.  Since the comedi device's main mutex
is heavily used, do a down-read of its `attach_lock` rwsemaphore
instead.  Trying to down-read `attach_lock` should only fail if
some task has down-write locked it, and that is only done while the
comedi device is being attached to or detached from a low-level hardware
device.

Unfortunately, acquiring the `attach_lock` doesn't prevent another
task replacing the comedi data buffer we are trying to mmap.  The
details of the buffer are held in a `struct comedi_buf_map` and pointed
to by `s->async->buf_map` where `s` is the comedi subdevice whose buffer
we are trying to map.  The `struct comedi_buf_map` is already reference
counted with a `struct kref`, so we can stop it being freed prematurely.

Modify `comedi_mmap()` to call new function
`comedi_buf_map_from_subdev_get()` to read the subdevice's current
buffer map pointer and increment its reference instead of accessing
`async->buf_map` directly.  Call `comedi_buf_map_put()` to decrement the
reference once the buffer map structure has been dealt with.  (Note that
`comedi_buf_map_put()` does nothing if passed a NULL pointer.)

`comedi_buf_map_from_subdev_get()` checks the subdevice's buffer map
pointer has been set and the buffer map has been initialized enough for
`comedi_mmap()` to deal with it (specifically, check the `n_pages`
member has been set to a non-zero value).  If all is well, the buffer
map's reference is incremented and a pointer to it is returned.  The
comedi subdevice's spin-lock is used to protect the checks.  Also use
the spin-lock in `__comedi_buf_alloc()` and `__comedi_buf_free()` to
protect changes to the subdevice's buffer map structure pointer and the
buffer map structure's `n_pages` member.  (This checking of `n_pages` is
a bit clunky and I [Ian Abbott] plan to deal with it in the future.)

Signed-off-by: Ian Abbott <[email protected]>
Cc: <[email protected]> # 3.14.x, 3.15.x
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Puneeth-n pushed a commit to Puneeth-n/linux that referenced this pull request Apr 23, 2014
When I open the LOCKDEP config and run these steps:

modprobe 8021q
vconfig add eth2 20
vconfig add eth2.20 30
ifconfig eth2 xx.xx.xx.xx

then the Call Trace happened:

[32524.386288] =============================================
[32524.386293] [ INFO: possible recursive locking detected ]
[32524.386298] 3.14.0-rc2-0.7-default+ torvalds#35 Tainted: G           O
[32524.386302] ---------------------------------------------
[32524.386306] ifconfig/3103 is trying to acquire lock:
[32524.386310]  (&vlan_netdev_addr_lock_key/1){+.....}, at: [<ffffffff814275f4>] dev_mc_sync+0x64/0xb0
[32524.386326]
[32524.386326] but task is already holding lock:
[32524.386330]  (&vlan_netdev_addr_lock_key/1){+.....}, at: [<ffffffff8141af83>] dev_set_rx_mode+0x23/0x40
[32524.386341]
[32524.386341] other info that might help us debug this:
[32524.386345]  Possible unsafe locking scenario:
[32524.386345]
[32524.386350]        CPU0
[32524.386352]        ----
[32524.386354]   lock(&vlan_netdev_addr_lock_key/1);
[32524.386359]   lock(&vlan_netdev_addr_lock_key/1);
[32524.386364]
[32524.386364]  *** DEADLOCK ***
[32524.386364]
[32524.386368]  May be due to missing lock nesting notation
[32524.386368]
[32524.386373] 2 locks held by ifconfig/3103:
[32524.386376]  #0:  (rtnl_mutex){+.+.+.}, at: [<ffffffff81431d42>] rtnl_lock+0x12/0x20
[32524.386387]  alexander-zimmermann#1:  (&vlan_netdev_addr_lock_key/1){+.....}, at: [<ffffffff8141af83>] dev_set_rx_mode+0x23/0x40
[32524.386398]
[32524.386398] stack backtrace:
[32524.386403] CPU: 1 PID: 3103 Comm: ifconfig Tainted: G           O 3.14.0-rc2-0.7-default+ torvalds#35
[32524.386409] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007
[32524.386414]  ffffffff81ffae40 ffff8800d9625ae8 ffffffff814f68a2 ffff8800d9625bc8
[32524.386421]  ffffffff810a35fb ffff8800d8a8d9d0 00000000d9625b28 ffff8800d8a8e5d0
[32524.386428]  000003cc00000000 0000000000000002 ffff8800d8a8e5f8 0000000000000000
[32524.386435] Call Trace:
[32524.386441]  [<ffffffff814f68a2>] dump_stack+0x6a/0x78
[32524.386448]  [<ffffffff810a35fb>] __lock_acquire+0x7ab/0x1940
[32524.386454]  [<ffffffff810a323a>] ? __lock_acquire+0x3ea/0x1940
[32524.386459]  [<ffffffff810a4874>] lock_acquire+0xe4/0x110
[32524.386464]  [<ffffffff814275f4>] ? dev_mc_sync+0x64/0xb0
[32524.386471]  [<ffffffff814fc07a>] _raw_spin_lock_nested+0x2a/0x40
[32524.386476]  [<ffffffff814275f4>] ? dev_mc_sync+0x64/0xb0
[32524.386481]  [<ffffffff814275f4>] dev_mc_sync+0x64/0xb0
[32524.386489]  [<ffffffffa0500cab>] vlan_dev_set_rx_mode+0x2b/0x50 [8021q]
[32524.386495]  [<ffffffff8141addf>] __dev_set_rx_mode+0x5f/0xb0
[32524.386500]  [<ffffffff8141af8b>] dev_set_rx_mode+0x2b/0x40
[32524.386506]  [<ffffffff8141b3cf>] __dev_open+0xef/0x150
[32524.386511]  [<ffffffff8141b177>] __dev_change_flags+0xa7/0x190
[32524.386516]  [<ffffffff8141b292>] dev_change_flags+0x32/0x80
[32524.386524]  [<ffffffff8149ca56>] devinet_ioctl+0x7d6/0x830
[32524.386532]  [<ffffffff81437b0b>] ? dev_ioctl+0x34b/0x660
[32524.386540]  [<ffffffff814a05b0>] inet_ioctl+0x80/0xa0
[32524.386550]  [<ffffffff8140199d>] sock_do_ioctl+0x2d/0x60
[32524.386558]  [<ffffffff81401a52>] sock_ioctl+0x82/0x2a0
[32524.386568]  [<ffffffff811a7123>] do_vfs_ioctl+0x93/0x590
[32524.386578]  [<ffffffff811b2705>] ? rcu_read_lock_held+0x45/0x50
[32524.386586]  [<ffffffff811b39e5>] ? __fget_light+0x105/0x110
[32524.386594]  [<ffffffff811a76b1>] SyS_ioctl+0x91/0xb0
[32524.386604]  [<ffffffff815057e2>] system_call_fastpath+0x16/0x1b

========================================================================

The reason is that all of the addr_lock_key for vlan dev have the same class,
so if we change the status for vlan dev, the vlan dev and its real dev will
hold the same class of addr_lock_key together, so the warning happened.

we should distinguish the lock depth for vlan dev and its real dev.

v1->v2: Convert the vlan_netdev_addr_lock_key to an array of eight elements, which
	could support to add 8 vlan id on a same vlan dev, I think it is enough for current
	scene, because a netdev's name is limited to IFNAMSIZ which could not hold 8 vlan id,
	and the vlan dev would not meet the same class key with its real dev.

	The new function vlan_dev_get_lockdep_subkey() will return the subkey and make the vlan
	dev could get a suitable class key.

v2->v3: According David's suggestion, I use the subclass to distinguish the lock key for vlan dev
	and its real dev, but it make no sense, because the difference for subclass in the
	lock_class_key doesn't mean that the difference class for lock_key, so I use lock_depth
	to distinguish the different depth for every vlan dev, the same depth of the vlan dev
	could have the same lock_class_key, I import the MAX_LOCK_DEPTH from the include/linux/sched.h,
	I think it is enough here, the lockdep should never exceed that value.

v3->v4: Add a huge array of locking keys will waste static kernel memory and is not a appropriate method,
	we could use _nested() variants to fix the problem, calculate the depth for every vlan dev,
	and use the depth as the subclass for addr_lock_key.

Signed-off-by: Ding Tianhong <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Puneeth-n pushed a commit to Puneeth-n/linux that referenced this pull request Apr 23, 2014
Currently, it is possible to create an SCTP socket, then switch
auth_enable via sysctl setting to 1 and crash the system on connect:

Oops[alexander-zimmermann#1]:
CPU: 0 PID: 0 Comm: swapper Not tainted 3.14.1-mipsgit-20140415 alexander-zimmermann#1
task: ffffffff8056ce80 ti: ffffffff8055c000 task.ti: ffffffff8055c000
[...]
Call Trace:
[<ffffffff8043c4e8>] sctp_auth_asoc_set_default_hmac+0x68/0x80
[<ffffffff8042b300>] sctp_process_init+0x5e0/0x8a4
[<ffffffff8042188c>] sctp_sf_do_5_1B_init+0x234/0x34c
[<ffffffff804228c8>] sctp_do_sm+0xb4/0x1e8
[<ffffffff80425a08>] sctp_endpoint_bh_rcv+0x1c4/0x214
[<ffffffff8043af68>] sctp_rcv+0x588/0x630
[<ffffffff8043e8e8>] sctp6_rcv+0x10/0x24
[<ffffffff803acb50>] ip6_input+0x2c0/0x440
[<ffffffff8030fc00>] __netif_receive_skb_core+0x4a8/0x564
[<ffffffff80310650>] process_backlog+0xb4/0x18c
[<ffffffff80313cbc>] net_rx_action+0x12c/0x210
[<ffffffff80034254>] __do_softirq+0x17c/0x2ac
[<ffffffff800345e0>] irq_exit+0x54/0xb0
[<ffffffff800075a4>] ret_from_irq+0x0/0x4
[<ffffffff800090ec>] rm7k_wait_irqoff+0x24/0x48
[<ffffffff8005e388>] cpu_startup_entry+0xc0/0x148
[<ffffffff805a88b0>] start_kernel+0x37c/0x398
Code: dd0900b8  000330f8  0126302d <dcc60000> 50c0fff1  0047182a  a48306a0
03e00008  00000000
---[ end trace b530b0551467f2fd ]---
Kernel panic - not syncing: Fatal exception in interrupt

What happens while auth_enable=0 in that case is, that
ep->auth_hmacs is initialized to NULL in sctp_auth_init_hmacs()
when endpoint is being created.

After that point, if an admin switches over to auth_enable=1,
the machine can crash due to NULL pointer dereference during
reception of an INIT chunk. When we enter sctp_process_init()
via sctp_sf_do_5_1B_init() in order to respond to an INIT chunk,
the INIT verification succeeds and while we walk and process
all INIT params via sctp_process_param() we find that
net->sctp.auth_enable is set, therefore do not fall through,
but invoke sctp_auth_asoc_set_default_hmac() instead, and thus,
dereference what we have set to NULL during endpoint
initialization phase.

The fix is to make auth_enable immutable by caching its value
during endpoint initialization, so that its original value is
being carried along until destruction. The bug seems to originate
from the very first days.

Fix in joint work with Daniel Borkmann.

Reported-by: Joshua Kinard <[email protected]>
Signed-off-by: Vlad Yasevich <[email protected]>
Signed-off-by: Daniel Borkmann <[email protected]>
Acked-by: Neil Horman <[email protected]>
Tested-by: Joshua Kinard <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
alexander-zimmermann pushed a commit that referenced this pull request Nov 20, 2014
This reverts commit 8b37e1b.

It's broken as it changes led_blink_set() in a way that it can now sleep
(while synchronously waiting for workqueue to be cancelled). That's a
problem, because it's possible that this function gets called from atomic
context (tpt_trig_timer() takes a readlock and thus disables preemption).

This has been brought up 3 weeks ago already [1] but no proper fix has
materialized, and I keep seeing the problem since 3.17-rc1.

[1] https://lkml.org/lkml/2014/8/16/128

 BUG: sleeping function called from invalid context at kernel/workqueue.c:2650
 in_atomic(): 1, irqs_disabled(): 0, pid: 2335, name: wpa_supplicant
 5 locks held by wpa_supplicant/2335:
  #0:  (rtnl_mutex){+.+.+.}, at: [<ffffffff814c7c92>] rtnl_lock+0x12/0x20
  #1:  (&wdev->mtx){+.+.+.}, at: [<ffffffffc06e649c>] cfg80211_mgd_wext_siwessid+0x5c/0x180 [cfg80211]
  #2:  (&local->mtx){+.+.+.}, at: [<ffffffffc0817dea>] ieee80211_prep_connection+0x17a/0x9a0 [mac80211]
  #3:  (&local->chanctx_mtx){+.+.+.}, at: [<ffffffffc08081ed>] ieee80211_vif_use_channel+0x5d/0x2a0 [mac80211]
  #4:  (&trig->leddev_list_lock){.+.+..}, at: [<ffffffffc081e68c>] tpt_trig_timer+0xec/0x170 [mac80211]
 CPU: 0 PID: 2335 Comm: wpa_supplicant Not tainted 3.17.0-rc3 #1
 Hardware name: LENOVO 7470BN2/7470BN2, BIOS 6DET38WW (2.02 ) 12/19/2008
  ffff8800360b5a50 ffff8800751f76d8 ffffffff8159e97f ffff8800360b5a30
  ffff8800751f76e8 ffffffff810739a5 ffff8800751f77b0 ffffffff8106862f
  ffffffff810685d0 0aa2209200000000 ffff880000000004 ffff8800361c59d0
 Call Trace:
  [<ffffffff8159e97f>] dump_stack+0x4d/0x66
  [<ffffffff810739a5>] __might_sleep+0xe5/0x120
  [<ffffffff8106862f>] flush_work+0x5f/0x270
  [<ffffffff810685d0>] ? mod_delayed_work_on+0x80/0x80
  [<ffffffff810945ca>] ? mark_held_locks+0x6a/0x90
  [<ffffffff81068a5f>] ? __cancel_work_timer+0x6f/0x100
  [<ffffffff810946ed>] ? trace_hardirqs_on_caller+0xfd/0x1c0
  [<ffffffff81068a6b>] __cancel_work_timer+0x7b/0x100
  [<ffffffff81068b0e>] cancel_delayed_work_sync+0xe/0x10
  [<ffffffff8147cf3b>] led_blink_set+0x1b/0x40
  [<ffffffffc081e6b0>] tpt_trig_timer+0x110/0x170 [mac80211]
  [<ffffffffc081ecdd>] ieee80211_mod_tpt_led_trig+0x9d/0x160 [mac80211]
  [<ffffffffc07e4278>] __ieee80211_recalc_idle+0x98/0x140 [mac80211]
  [<ffffffffc07e59ce>] ieee80211_idle_off+0xe/0x10 [mac80211]
  [<ffffffffc0804e5b>] ieee80211_add_chanctx+0x3b/0x220 [mac80211]
  [<ffffffffc08062e4>] ieee80211_new_chanctx+0x44/0xf0 [mac80211]
  [<ffffffffc080838a>] ieee80211_vif_use_channel+0x1fa/0x2a0 [mac80211]
  [<ffffffffc0817df8>] ieee80211_prep_connection+0x188/0x9a0 [mac80211]
  [<ffffffffc081c246>] ieee80211_mgd_auth+0x256/0x2e0 [mac80211]
  [<ffffffffc07eab33>] ieee80211_auth+0x13/0x20 [mac80211]
  [<ffffffffc06cb006>] cfg80211_mlme_auth+0x106/0x270 [cfg80211]
  [<ffffffffc06ce085>] cfg80211_conn_do_work+0x155/0x3b0 [cfg80211]
  [<ffffffffc06cf670>] cfg80211_connect+0x3f0/0x540 [cfg80211]
  [<ffffffffc06e6148>] cfg80211_mgd_wext_connect+0x158/0x1f0 [cfg80211]
  [<ffffffffc06e651e>] cfg80211_mgd_wext_siwessid+0xde/0x180 [cfg80211]
  [<ffffffffc06e36c0>] ? cfg80211_wext_giwessid+0x50/0x50 [cfg80211]
  [<ffffffffc06e36dd>] cfg80211_wext_siwessid+0x1d/0x40 [cfg80211]
  [<ffffffff81584d0c>] ioctl_standard_iw_point+0x14c/0x3e0
  [<ffffffff810946ed>] ? trace_hardirqs_on_caller+0xfd/0x1c0
  [<ffffffff8158502a>] ioctl_standard_call+0x8a/0xd0
  [<ffffffff81584fa0>] ? ioctl_standard_iw_point+0x3e0/0x3e0
  [<ffffffff81584b76>] wireless_process_ioctl.constprop.10+0xb6/0x100
  [<ffffffff8158521d>] wext_handle_ioctl+0x5d/0xb0
  [<ffffffff814cfb29>] dev_ioctl+0x329/0x620
  [<ffffffff810946ed>] ? trace_hardirqs_on_caller+0xfd/0x1c0
  [<ffffffff8149c7f2>] sock_ioctl+0x142/0x2e0
  [<ffffffff811b0140>] do_vfs_ioctl+0x300/0x520
  [<ffffffff815a67fb>] ? sysret_check+0x1b/0x56
  [<ffffffff810946ed>] ? trace_hardirqs_on_caller+0xfd/0x1c0
  [<ffffffff811b03e1>] SyS_ioctl+0x81/0xa0
  [<ffffffff815a67d6>] system_call_fastpath+0x1a/0x1f
 wlan0: send auth to 00:0b:6b:3c:8c:e4 (try 1/3)
 wlan0: authenticated
 wlan0: associate with 00:0b:6b:3c:8c:e4 (try 1/3)
 wlan0: RX AssocResp from 00:0b:6b:3c:8c:e4 (capab=0x431 status=0 aid=2)
 wlan0: associated
 IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready
 cfg80211: Calling CRDA for country: NA
 wlan0: Limiting TX power to 27 (27 - 0) dBm as advertised by 00:0b:6b:3c:8c:e4

 =================================
 [ INFO: inconsistent lock state ]
 3.17.0-rc3 #1 Not tainted
 ---------------------------------
 inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
 swapper/0/0 [HC0[0]:SC1[1]:HE1:SE0] takes:
  ((&(&led_cdev->blink_work)->work)){+.?...}, at: [<ffffffff810685d0>] flush_work+0x0/0x270
 {SOFTIRQ-ON-W} state was registered at:
   [<ffffffff81094dbe>] __lock_acquire+0x30e/0x1a30
   [<ffffffff81096c81>] lock_acquire+0x91/0x110
   [<ffffffff81068608>] flush_work+0x38/0x270
   [<ffffffff81068a6b>] __cancel_work_timer+0x7b/0x100
   [<ffffffff81068b0e>] cancel_delayed_work_sync+0xe/0x10
   [<ffffffff8147cf3b>] led_blink_set+0x1b/0x40
   [<ffffffffc081e6b0>] tpt_trig_timer+0x110/0x170 [mac80211]
   [<ffffffffc081ecdd>] ieee80211_mod_tpt_led_trig+0x9d/0x160 [mac80211]
   [<ffffffffc07e4278>] __ieee80211_recalc_idle+0x98/0x140 [mac80211]
   [<ffffffffc07e59ce>] ieee80211_idle_off+0xe/0x10 [mac80211]
   [<ffffffffc0804e5b>] ieee80211_add_chanctx+0x3b/0x220 [mac80211]
   [<ffffffffc08062e4>] ieee80211_new_chanctx+0x44/0xf0 [mac80211]
   [<ffffffffc080838a>] ieee80211_vif_use_channel+0x1fa/0x2a0 [mac80211]
   [<ffffffffc0817df8>] ieee80211_prep_connection+0x188/0x9a0 [mac80211]
   [<ffffffffc081c246>] ieee80211_mgd_auth+0x256/0x2e0 [mac80211]
   [<ffffffffc07eab33>] ieee80211_auth+0x13/0x20 [mac80211]
   [<ffffffffc06cb006>] cfg80211_mlme_auth+0x106/0x270 [cfg80211]
   [<ffffffffc06ce085>] cfg80211_conn_do_work+0x155/0x3b0 [cfg80211]
   [<ffffffffc06cf670>] cfg80211_connect+0x3f0/0x540 [cfg80211]
   [<ffffffffc06e6148>] cfg80211_mgd_wext_connect+0x158/0x1f0 [cfg80211]
   [<ffffffffc06e651e>] cfg80211_mgd_wext_siwessid+0xde/0x180 [cfg80211]
   [<ffffffffc06e36dd>] cfg80211_wext_siwessid+0x1d/0x40 [cfg80211]
   [<ffffffff81584d0c>] ioctl_standard_iw_point+0x14c/0x3e0
   [<ffffffff8158502a>] ioctl_standard_call+0x8a/0xd0
   [<ffffffff81584b76>] wireless_process_ioctl.constprop.10+0xb6/0x100
   [<ffffffff8158521d>] wext_handle_ioctl+0x5d/0xb0
   [<ffffffff814cfb29>] dev_ioctl+0x329/0x620
   [<ffffffff8149c7f2>] sock_ioctl+0x142/0x2e0
   [<ffffffff811b0140>] do_vfs_ioctl+0x300/0x520
   [<ffffffff811b03e1>] SyS_ioctl+0x81/0xa0
   [<ffffffff815a67d6>] system_call_fastpath+0x1a/0x1f
 irq event stamp: 493416
 hardirqs last  enabled at (493416): [<ffffffff81068a5f>] __cancel_work_timer+0x6f/0x100
 hardirqs last disabled at (493415): [<ffffffff81067e9f>] try_to_grab_pending+0x1f/0x160
 softirqs last  enabled at (493408): [<ffffffff81053ced>] _local_bh_enable+0x1d/0x50
 softirqs last disabled at (493409): [<ffffffff81054c75>] irq_exit+0xa5/0xb0

 other info that might help us debug this:
  Possible unsafe locking scenario:

        CPU0
        ----
   lock((&(&led_cdev->blink_work)->work));
   <Interrupt>
     lock((&(&led_cdev->blink_work)->work));

  *** DEADLOCK ***

 2 locks held by swapper/0/0:
  #0:  (((&tpt_trig->timer))){+.-...}, at: [<ffffffff810b4c50>] call_timer_fn+0x0/0x180
  #1:  (&trig->leddev_list_lock){.+.?..}, at: [<ffffffffc081e68c>] tpt_trig_timer+0xec/0x170 [mac80211]

 stack backtrace:
 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.17.0-rc3 #1
 Hardware name: LENOVO 7470BN2/7470BN2, BIOS 6DET38WW (2.02 ) 12/19/2008
  ffffffff8246eb30 ffff88007c203b00 ffffffff8159e97f ffffffff81a194c0
  ffff88007c203b50 ffffffff81599c29 0000000000000001 ffffffff00000001
  ffff880000000000 0000000000000006 ffffffff81a194c0 ffffffff81093ad0
 Call Trace:
  <IRQ>  [<ffffffff8159e97f>] dump_stack+0x4d/0x66
  [<ffffffff81599c29>] print_usage_bug+0x1f4/0x205
  [<ffffffff81093ad0>] ? check_usage_backwards+0x140/0x140
  [<ffffffff810944d3>] mark_lock+0x223/0x2b0
  [<ffffffff81094d60>] __lock_acquire+0x2b0/0x1a30
  [<ffffffff81096c81>] lock_acquire+0x91/0x110
  [<ffffffff810685d0>] ? mod_delayed_work_on+0x80/0x80
  [<ffffffffc081e5a0>] ? __ieee80211_get_rx_led_name+0x10/0x10 [mac80211]
  [<ffffffff81068608>] flush_work+0x38/0x270
  [<ffffffff810685d0>] ? mod_delayed_work_on+0x80/0x80
  [<ffffffff810945ca>] ? mark_held_locks+0x6a/0x90
  [<ffffffff81068a5f>] ? __cancel_work_timer+0x6f/0x100
  [<ffffffffc081e5a0>] ? __ieee80211_get_rx_led_name+0x10/0x10 [mac80211]
  [<ffffffff8109469d>] ? trace_hardirqs_on_caller+0xad/0x1c0
  [<ffffffffc081e5a0>] ? __ieee80211_get_rx_led_name+0x10/0x10 [mac80211]
  [<ffffffff81068a6b>] __cancel_work_timer+0x7b/0x100
  [<ffffffff81068b0e>] cancel_delayed_work_sync+0xe/0x10
  [<ffffffff8147cf3b>] led_blink_set+0x1b/0x40
  [<ffffffffc081e6b0>] tpt_trig_timer+0x110/0x170 [mac80211]
  [<ffffffff810b4cc5>] call_timer_fn+0x75/0x180
  [<ffffffff810b4c50>] ? process_timeout+0x10/0x10
  [<ffffffffc081e5a0>] ? __ieee80211_get_rx_led_name+0x10/0x10 [mac80211]
  [<ffffffff810b50ac>] run_timer_softirq+0x1fc/0x2f0
  [<ffffffff81054805>] __do_softirq+0x115/0x2e0
  [<ffffffff81054c75>] irq_exit+0xa5/0xb0
  [<ffffffff810049b3>] do_IRQ+0x53/0xf0
  [<ffffffff815a74af>] common_interrupt+0x6f/0x6f
  <EOI>  [<ffffffff8147b56e>] ? cpuidle_enter_state+0x6e/0x180
  [<ffffffff8147b732>] cpuidle_enter+0x12/0x20
  [<ffffffff8108bba0>] cpu_startup_entry+0x330/0x360
  [<ffffffff8158fb51>] rest_init+0xc1/0xd0
  [<ffffffff8158fa90>] ? csum_partial_copy_generic+0x170/0x170
  [<ffffffff81af3ff2>] start_kernel+0x44f/0x45a
  [<ffffffff81af399c>] ? set_init_arg+0x53/0x53
  [<ffffffff81af35ad>] x86_64_start_reservations+0x2a/0x2c
  [<ffffffff81af36a0>] x86_64_start_kernel+0xf1/0xf4

Cc: Vincent Donnefort <[email protected]>
Cc: Hugh Dickins <[email protected]>
Cc: Tejun Heo <[email protected]>
Signed-off-by: Jiri Kosina <[email protected]>
Signed-off-by: Bryan Wu <[email protected]>
alexander-zimmermann pushed a commit that referenced this pull request Nov 20, 2014
While doing a ranged fsync, that is, one whose range doesn't cover the
whole possible file range (0 to LLONG_MAX), we can crash under certain
circumstances with a trace like the following:

[41074.641913] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC
(...)
[41074.642692] CPU: 0 PID: 24580 Comm: fsx Not tainted 3.16.0-fdm-btrfs-next-45+ #1
(...)
[41074.643886] RIP: 0010:[<ffffffffa01ecc99>]  [<ffffffffa01ecc99>] btrfs_ordered_update_i_size+0x279/0x2b0 [btrfs]
(...)
[41074.644919] Stack:
(...)
[41074.644919] Call Trace:
[41074.644919]  [<ffffffffa01db531>] btrfs_truncate_inode_items+0x3f1/0xa10 [btrfs]
[41074.644919]  [<ffffffffa01eb54f>] ? btrfs_get_logged_extents+0x4f/0x80 [btrfs]
[41074.644919]  [<ffffffffa02137a9>] btrfs_log_inode+0x2f9/0x970 [btrfs]
[41074.644919]  [<ffffffff81090875>] ? sched_clock_local+0x25/0xa0
[41074.644919]  [<ffffffff8164a55e>] ? mutex_unlock+0xe/0x10
[41074.644919]  [<ffffffff810af51d>] ? trace_hardirqs_on+0xd/0x10
[41074.644919]  [<ffffffffa0214b4f>] btrfs_log_inode_parent+0x1ef/0x560 [btrfs]
[41074.644919]  [<ffffffff811d0c55>] ? dget_parent+0x5/0x180
[41074.644919]  [<ffffffffa0215d11>] btrfs_log_dentry_safe+0x51/0x80 [btrfs]
[41074.644919]  [<ffffffffa01e2d1a>] btrfs_sync_file+0x1ba/0x3e0 [btrfs]
[41074.644919]  [<ffffffff811eda6b>] vfs_fsync_range+0x1b/0x30
(...)

The necessary conditions that lead to such crash are:

* an incremental fsync (when the inode doesn't have the
  BTRFS_INODE_NEEDS_FULL_SYNC flag set) happened for our file and it logged
  a file extent item ending at offset X;

* the file got the flag BTRFS_INODE_NEEDS_FULL_SYNC set in its inode, due
  to a file truncate operation that reduces the file to a size smaller
  than X;

* a ranged fsync call happens (via an msync for example), with a range that
  doesn't cover the whole file and the end of this range, lets call it Y, is
  smaller than X;

* btrfs_log_inode, sees the flag BTRFS_INODE_NEEDS_FULL_SYNC set and
  calls btrfs_truncate_inode_items() to remove all items from the log
  tree that are associated with our file;

* btrfs_truncate_inode_items() removes all of the inode's items, and the lowest
  file extent item it removed is the one ending at offset X, where X > 0 and
  X > Y - before returning, it calls btrfs_ordered_update_i_size() with an offset
  parameter set to X;

* btrfs_ordered_update_i_size() sees that X is greater then the current ordered
  size (btrfs_inode's disk_i_size) and then it assumes there can't be any ongoing
  ordered operation with a range covering the offset X, calling a BUG_ON() if
  such ordered operation exists. This assumption is made because the disk_i_size
  is only increased after the corresponding file extent item is added to the
  btree (btrfs_finish_ordered_io);

* But because our fsync covers only a limited range, such an ordered extent might
  exist, and our fsync callback (btrfs_sync_file) doesn't wait for such ordered
  extent to finish when calling btrfs_wait_ordered_range();

And then by the time btrfs_ordered_update_i_size() is called, via:

   btrfs_sync_file() ->
       btrfs_log_dentry_safe() ->
           btrfs_log_inode_parent() ->
               btrfs_log_inode() ->
                   btrfs_truncate_inode_items() ->
                       btrfs_ordered_update_i_size()

We hit the BUG_ON(), which could never happen if the fsync range covered the whole
possible file range (0 to LLONG_MAX), as we would wait for all ordered extents to
finish before calling btrfs_truncate_inode_items().

So just don't call btrfs_ordered_update_i_size() if we're removing the inode's items
from a log tree, which isn't supposed to change the in memory inode's disk_i_size.

Issue found while running xfstests/generic/127 (happens very rarely for me), more
specifically via the fsx calls that use memory mapped IO (and issue msync calls).

Signed-off-by: Filipe Manana <[email protected]>
Signed-off-by: Chris Mason <[email protected]>
alexander-zimmermann pushed a commit that referenced this pull request Nov 20, 2014
Some gadget drivers will call usb_ep_queue() more than once before
the first queue doesn't finish. However, this driver didn't handle
it correctly. So, this patch fixes the behavior of some
usbhs_pkt_handle using the "running" flag. Otherwise, the oops below
happens if we use g_ncm driver and when the "iperf -u -c host -b 200M"
is running.

Unable to handle kernel NULL pointer dereference at virtual address 00000000
pgd = c0004000
[00000000] *pgd=00000000
Internal error: Oops: 80000007 [#1] SMP ARM
Modules linked in: usb_f_ncm g_ncm libcomposite u_ether
CPU: 0 PID: 0 Comm: swapper/0 Tainted: G        W      3.17.0-rc1-00008-g8b2be8a-dirty torvalds#20
task: c051c7e0 ti: c0512000 task.ti: c0512000
PC is at 0x0
LR is at usbhsf_pkt_handler+0xa8/0x114
pc : [<00000000>]    lr : [<c0278fb4>]    psr: 60000193
sp : c0513ce8  ip : c0513c58  fp : c0513d24
r10: 00000001  r9 : 00000193  r8 : eebec4a0
r7 : eebec410  r6 : eebe0c6c  r5 : 00000000  r4 : ee4a2774
r3 : 00000000  r2 : ee251e00  r1 : c0513cf4  r0 : ee4a2774

Signed-off-by: Yoshihiro Shimoda <[email protected]>
Signed-off-by: Felipe Balbi <[email protected]>
alexander-zimmermann pushed a commit that referenced this pull request Nov 20, 2014
…fixes

Merge "at91: fixes for 3.17 #1" from Nicols Ferre:

First AT91 fixes batch for 3.17:
- compatibility string precision
- clock registration and USB DT fix for at91rm9200

* tag 'at91-fixes' of git://github.com/at91linux/linux-at91:
  ARM: at91/dt: rm9200: fix usb clock definition
  ARM: at91: rm9200: fix clock registration
  ARM: at91/dt: sam9g20: set at91sam9g20 pllb driver

Signed-off-by: Kevin Hilman <[email protected]>
alexander-zimmermann pushed a commit that referenced this pull request Nov 20, 2014
Use dst_entry held by sk_dst_get() to retrieve tunnel's PMTU.

The dst_mtu(__sk_dst_get(tunnel->sock)) call was racy. __sk_dst_get()
could return NULL if tunnel->sock->sk_dst_cache was reset just before the
call, thus making dst_mtu() dereference a NULL pointer:

[ 1937.661598] BUG: unable to handle kernel NULL pointer dereference at 0000000000000020
[ 1937.664005] IP: [<ffffffffa049db88>] pppol2tp_connect+0x33d/0x41e [l2tp_ppp]
[ 1937.664005] PGD daf0c067 PUD d9f93067 PMD 0
[ 1937.664005] Oops: 0000 [#1] SMP
[ 1937.664005] Modules linked in: l2tp_ppp l2tp_netlink l2tp_core ip6table_filter ip6_tables iptable_filter ip_tables ebtable_nat ebtables x_tables udp_tunnel pppoe pppox ppp_generic slhc deflate ctr twofish_generic twofish_x86_64_3way xts lrw gf128mul glue_helper twofish_x86_64 twofish_common blowfish_generic blowfish_x86_64 blowfish_common des_generic cbc xcbc rmd160 sha512_generic hmac crypto_null af_key xfrm_algo 8021q garp bridge stp llc tun atmtcp clip atm ext3 mbcache jbd iTCO_wdt coretemp kvm_intel iTCO_vendor_support kvm pcspkr evdev ehci_pci lpc_ich mfd_core i5400_edac edac_core i5k_amb shpchp button processor thermal_sys xfs crc32c_generic libcrc32c dm_mod usbhid sg hid sr_mod sd_mod cdrom crc_t10dif crct10dif_common ata_generic ahci ata_piix tg3 libahci libata uhci_hcd ptp ehci_hcd pps_core usbcore scsi_mod libphy usb_common [last unloaded: l2tp_core]
[ 1937.664005] CPU: 0 PID: 10022 Comm: l2tpstress Tainted: G           O   3.17.0-rc1 #1
[ 1937.664005] Hardware name: HP ProLiant DL160 G5, BIOS O12 08/22/2008
[ 1937.664005] task: ffff8800d8fda790 ti: ffff8800c43c4000 task.ti: ffff8800c43c4000
[ 1937.664005] RIP: 0010:[<ffffffffa049db88>]  [<ffffffffa049db88>] pppol2tp_connect+0x33d/0x41e [l2tp_ppp]
[ 1937.664005] RSP: 0018:ffff8800c43c7de8  EFLAGS: 00010282
[ 1937.664005] RAX: ffff8800da8a7240 RBX: ffff8800d8c64600 RCX: 000001c325a137b5
[ 1937.664005] RDX: 8c6318c6318c6320 RSI: 000000000000010c RDI: 0000000000000000
[ 1937.664005] RBP: ffff8800c43c7ea8 R08: 0000000000000000 R09: 0000000000000000
[ 1937.664005] R10: ffffffffa048e2c0 R11: ffff8800d8c64600 R12: ffff8800ca7a5000
[ 1937.664005] R13: ffff8800c439bf40 R14: 000000000000000c R15: 0000000000000009
[ 1937.664005] FS:  00007fd7f610f700(0000) GS:ffff88011a600000(0000) knlGS:0000000000000000
[ 1937.664005] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[ 1937.664005] CR2: 0000000000000020 CR3: 00000000d9d75000 CR4: 00000000000027e0
[ 1937.664005] Stack:
[ 1937.664005]  ffffffffa049da80 ffff8800d8fda790 000000000000005b ffff880000000009
[ 1937.664005]  ffff8800daf3f200 0000000000000003 ffff8800c43c7e48 ffffffff81109b57
[ 1937.664005]  ffffffff81109b0e ffffffff8114c566 0000000000000000 0000000000000000
[ 1937.664005] Call Trace:
[ 1937.664005]  [<ffffffffa049da80>] ? pppol2tp_connect+0x235/0x41e [l2tp_ppp]
[ 1937.664005]  [<ffffffff81109b57>] ? might_fault+0x9e/0xa5
[ 1937.664005]  [<ffffffff81109b0e>] ? might_fault+0x55/0xa5
[ 1937.664005]  [<ffffffff8114c566>] ? rcu_read_unlock+0x1c/0x26
[ 1937.664005]  [<ffffffff81309196>] SYSC_connect+0x87/0xb1
[ 1937.664005]  [<ffffffff813e56f7>] ? sysret_check+0x1b/0x56
[ 1937.664005]  [<ffffffff8107590d>] ? trace_hardirqs_on_caller+0x145/0x1a1
[ 1937.664005]  [<ffffffff81213dee>] ? trace_hardirqs_on_thunk+0x3a/0x3f
[ 1937.664005]  [<ffffffff8114c262>] ? spin_lock+0x9/0xb
[ 1937.664005]  [<ffffffff813092b4>] SyS_connect+0x9/0xb
[ 1937.664005]  [<ffffffff813e56d2>] system_call_fastpath+0x16/0x1b
[ 1937.664005] Code: 10 2a 84 81 e8 65 76 bd e0 65 ff 0c 25 10 bb 00 00 4d 85 ed 74 37 48 8b 85 60 ff ff ff 48 8b 80 88 01 00 00 48 8b b8 10 02 00 00 <48> 8b 47 20 ff 50 20 85 c0 74 0f 83 e8 28 89 83 10 01 00 00 89
[ 1937.664005] RIP  [<ffffffffa049db88>] pppol2tp_connect+0x33d/0x41e [l2tp_ppp]
[ 1937.664005]  RSP <ffff8800c43c7de8>
[ 1937.664005] CR2: 0000000000000020
[ 1939.559375] ---[ end trace 82d44500f28f8708 ]---

Fixes: f34c4a3 ("l2tp: take PMTU from tunnel UDP socket")
Signed-off-by: Guillaume Nault <[email protected]>
Acked-by: Eric Dumazet <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
alexander-zimmermann pushed a commit that referenced this pull request Nov 20, 2014
This bug was reported on a very old kernel (RHEL6, 2.6.32-491.el6):

BUG: unable to handle kernel paging request at 00800000
IP: [<c04107b5>] nommu_map_page+0x15/0x110
*pdpt = 000000003454f001 *pde = 000000003f03d067
Oops: 0000 [#1] SMP
last sysfs file: /sys/devices/system/cpu/online
Modules linked in: nfsd lockd nfs_acl auth_rpcgss sunrpc exportfs p4_clockmod
ipv6 ppdev parport_pc parport microcode iTCO_wdt iTCO_vendor_support 3c59x mii
dcdbas serio_raw snd_intel8x0 snd_ac97_codec ac97_bus snd_seq snd_seq_device
snd_pcm snd_timer snd soundcore snd_page_alloc i2c_i801 sg lpc_ich mfd_core ext4
jbd2 mbcache sr_mod cdrom sd_mod crc_t10dif pata_acpi ata_generic ata_piix
radeon ttm drm_kms_helper drm i2c_algo_bit i2c_core dm_mirror dm_region_hash
dm_log dm_mod [last unloaded: mperf]

Pid: 4219, comm: nfsd Not tainted 2.6.32-491.el6.i686 #1 Dell Computer
Corporation OptiPlex GX240               /OptiPlex GX240
EIP: 0060:[<c04107b5>] EFLAGS: 00010246 CPU: 0
EIP is at nommu_map_page+0x15/0x110
EAX: 00000000 EBX: c0a83480 ECX: 00000000 EDX: 00800000
ESI: 00000000 EDI: f70e7860 EBP: e2d09b54 ESP: e2d09b24
 DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
Process nfsd (pid: 4219, ti=e2d08000 task=e2ceaaa0 task.ti=e2d08000)
Stack:
 00000056 00000000 0000000e c65efd38 00000020 00000296 00000206 00000206
<0> c050c85 c0a83480 e2cef154 00000001 e2d09ba8 f8fcd585 00000510 00000001
<0> 00000000 00000000 f5172200 f8fdac00 0039ef8c f5277020 f70e7860 00000510
Call Trace:
 [<c050c850>] ? page_address+0xd0/0xe0
 [<f8fcd585>] ? boomerang_start_xmit+0x3b5/0x520 [3c59x]
 [<c07b2975>] ? dev_hard_start_xmit+0xe5/0x400
 [<f9182b00>] ? ip6_output_finish+0x0/0xf0 [ipv6]
 [<c07ca053>] ? sch_direct_xmit+0x113/0x180
 [<c07d5588>] ? nf_hook_slow+0x68/0x120
 [<c07b2ea5>] ? dev_queue_xmit+0x1b5/0x290
 [<f9182b6d>] ? ip6_output_finish+0x6d/0xf0 [ipv6]
 [<f9184cb8>] ? ip6_xmit+0x3e8/0x490 [ipv6]
 [<f91ab9f9>] ? inet6_csk_xmit+0x289/0x2f0 [ipv6]
 [<c07f6451>] ? tcp_transmit_skb+0x431/0x7f0
 [<c07a403f>] ? __alloc_skb+0x4f/0x140
 [<c07f85a2>] ? tcp_write_xmit+0x1c2/0xa50
 [<c07f90b1>] ? __tcp_push_pending_frames+0x31/0xe0
 [<c07ea47a>] ? tcp_sendpage+0x44a/0x4b0
 [<c07ea030>] ? tcp_sendpage+0x0/0x4b0
 [<c079be1e>] ? kernel_sendpage+0x4e/0x90
 [<f8457bb9>] ? svc_send_common+0xc9/0x120 [sunrpc]
 [<f8457c85>] ? svc_sendto+0x75/0x1f0 [sunrpc]
 [<c060d0d9>] ? _atomic_dec_and_lock+0x59/0x90
 [<f87d55d0>] ? nfs3svc_encode_readres+0x0/0xc0 [nfsd]
 [<f845876d>] ? svc_authorise+0x2d/0x40 [sunrpc]
 [<f87d4410>] ? nfs3svc_release_fhandle+0x0/0x10 [nfsd]
 [<f8455721>] ? svc_process_common+0xf1/0x5a0 [sunrpc]
 [<f8457e86>] ? svc_tcp_sendto+0x36/0xa0 [sunrpc]
 [<f8461778>] ? svc_send+0x98/0xd0 [sunrpc]
 [<f87c698c>] ? nfsd+0xac/0x140 [nfsd]
 [<c04470e0>] ? complete+0x40/0x60
 [<f87c68e0>] ? nfsd+0x0/0x140 [nfsd]
 [<c04802ac>] ? kthread+0x7c/0xa0
 [<c0480230>] ? kthread+0x0/0xa0
 [<c0409f9f>] ? kernel_thread_helper+0x7/0x10
Code: 8d b6 00 00 00 00 eb f8 8d b4 26 00 00 00 00 8d bc 27 00 00 00 00 55 89 e5
83 ec 30 89 75 f8 31 f6 89 7d fc 89 c7 89 c8 89 5d f4 <8b> 1a 8b 4d 08 c1 eb 19
c1 e3 04 8b 9b c0 29 c7 c0 83 e3 fc 29

But the problem seems to still exist upstream.  It seems on 32 bit kernels
page_address() can reutrn a NULL value in some circumstances, and the
pci_map_single api isn't prepared to handle that (on this system it results in a
bogus pointer deference in nommu_map_page.

The fix is pretty easy, if we convert the 3c59x driver to use the more
convieient skb_frag_dma_map api we don't need to find the virtual address of the
page at all, and page gets mapped to the hardware properly.  Verified to fix the
problem as described by the reporter.

Applies to the net tree

Change Notes:

v2) Converted PCI_DMA_TODEVICE to DMA_TO_DEVICE.  Thanks Dave!

v3) Actually Run git commit after making changes to v2 :)

Signed-off-by: Neil Horman <[email protected]>
CC: [email protected]
CC: "David S. Miller" <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
alexander-zimmermann pushed a commit that referenced this pull request Nov 20, 2014
During release of the GEM object we hold the struct_mutex. As the
object may be holding onto the last reference for the task->mm,
calling mmput() may trigger exit_mmap() which close the vma
which will call drm_gem_vm_close() and attempt to reacquire
the struct_mutex. In order to avoid that recursion, we have
to defer the mmput() until after we drop the struct_mutex,
i.e. we need to schedule a worker to do the clean up. A further issue
spotted by Tvrtko was caused when we took a GTT mmapping of a userptr
buffer object. In that case, we would never call mmput as the object
would be cyclically referenced by the GTT mmapping and not freed upon
process exit - keeping the entire process mm alive after the process
task was reaped. The fix employed is to replace the mm_users/mmput()
reference handling to mm_count/mmdrop() for the shared i915_mm_struct.

   INFO: task test_surfaces:1632 blocked for more than 120 seconds.
         Tainted: GF          O 3.14.5+ #1
   "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
   test_surfaces   D 0000000000000000     0  1632   1590 0x00000082
    ffff88014914baa8 0000000000000046 0000000000000000 ffff88014914a010
    0000000000012c40 0000000000012c40 ffff8800a0058210 ffff88014784b010
    ffff88014914a010 ffff880037b1c820 ffff8800a0058210 ffff880037b1c824
   Call Trace:
    [<ffffffff81582499>] schedule+0x29/0x70
    [<ffffffff815825fe>] schedule_preempt_disabled+0xe/0x10
    [<ffffffff81583b93>] __mutex_lock_slowpath+0x183/0x220
    [<ffffffff81583c53>] mutex_lock+0x23/0x40
    [<ffffffffa005c2a3>] drm_gem_vm_close+0x33/0x70 [drm]
    [<ffffffff8115a483>] remove_vma+0x33/0x70
    [<ffffffff8115a5dc>] exit_mmap+0x11c/0x170
    [<ffffffff8104d6eb>] mmput+0x6b/0x100
    [<ffffffffa00f44b9>] i915_gem_userptr_release+0x89/0xc0 [i915]
    [<ffffffffa00e6706>] i915_gem_free_object+0x126/0x250 [i915]
    [<ffffffffa005c06a>] drm_gem_object_free+0x2a/0x40 [drm]
    [<ffffffffa005cc32>] drm_gem_object_handle_unreference_unlocked+0xe2/0x120 [drm]
    [<ffffffffa005ccd4>] drm_gem_object_release_handle+0x64/0x90 [drm]
    [<ffffffff8127ffeb>] idr_for_each+0xab/0x100
    [<ffffffffa005cc70>] ?  drm_gem_object_handle_unreference_unlocked+0x120/0x120 [drm]
    [<ffffffff81583c46>] ? mutex_lock+0x16/0x40
    [<ffffffffa005c354>] drm_gem_release+0x24/0x40 [drm]
    [<ffffffffa005b82b>] drm_release+0x3fb/0x480 [drm]
    [<ffffffff8118d482>] __fput+0xb2/0x260
    [<ffffffff8118d6de>] ____fput+0xe/0x10
    [<ffffffff8106f27f>] task_work_run+0x8f/0xf0
    [<ffffffff81052228>] do_exit+0x1a8/0x480
    [<ffffffff81052551>] do_group_exit+0x51/0xc0
    [<ffffffff810525d7>] SyS_exit_group+0x17/0x20
    [<ffffffff8158e092>] system_call_fastpath+0x16/0x1b

v2: Incorporate feedback from Tvrtko and remove the unnessary mm
referencing when creating the i915_mm_struct and improve some of the
function names and comments.

Reported-by: Jacek Danecki <[email protected]>
Test-case: igt/gem_userptr_blits/process-exit*
Signed-off-by: Chris Wilson <[email protected]>
Tested-by: "Gong, Zhipeng" <[email protected]>
Cc: Jacek Danecki <[email protected]>
Cc: "Ursulin, Tvrtko" <[email protected]>
Reviewed-by: "Ursulin, Tvrtko" <[email protected]>
Signed-off-by: Daniel Vetter <[email protected]>
Cc: [email protected] # hold off until 3.17 ships for additional testing
Signed-off-by: Jani Nikula <[email protected]>
alexander-zimmermann pushed a commit that referenced this pull request Nov 20, 2014
Nikita Yuschenko reported that booting a kernel with init=/bin/sh and
then nfs mounting without portmap or rpcbind running using a busybox
mount resulted in:

  # mount -t nfs 10.30.130.21:/opt /mnt
  svc: failed to register lockdv1 RPC service (errno 111).
  lockd_up: makesock failed, error=-111
  Unable to handle kernel paging request for data at address 0x00000030
  Faulting instruction address: 0xc055e65c
  Oops: Kernel access of bad area, sig: 11 [#1]
  MPC85xx CDS
  Modules linked in:
  CPU: 0 PID: 1338 Comm: mount Not tainted 3.10.44.cge torvalds#117
  task: cf29cea0 ti: cf35c00 task.ti: cf35c00
  NIP: c055e65c LR: c056649 CTR: c055e648
  REGS: cf35dad0 TRAP: 0300   Not tainted  (3.10.44.cge)
  MSR: 00029000 <CE,EE,ME>  CR: 22442488  XER: 20000000
  DEAR: 00000030, ESR: 00000000

  GPR00: c05606f4 cf35db80 cf29cea0 cf0ded80 cf0dedb8 00000001 1dec3086
  00000000
  GPR08: 00000000 c07b1640 00000007 1dec3086 22442482 100b9758 00000000
  10090ae8
  GPR16: 00000000 000186a5 00000000 00000000 100c3018 bfa46edc 100b0000
  bfa46ef0
  GPR24: cf386ae0 c07834f0 00000000 c0565f88 00000001 cf0dedb8 00000000
  cf0ded80
  NIP [c055e65c] call_start+0x14/0x34
  LR [c056649] __rpc_execute+0x70/0x250
  Call Trace:
  [cf35db80] [00000080] 0x80 (unreliable)
  [cf35dbb0] [c05606f4] rpc_run_task+0x9c/0xc4
  [cf35dbc0] [c0560840] rpc_call_sync+0x50/0xb8
  [cf35dbf0] [c056ee90] rpcb_register_call+0x54/0x84
  [cf35dc10] [c056f24c] rpcb_register+0xf8/0x10c
  [cf35dc70] [c0569e18] svc_unregister.isra.23+0x100/0x108
  [cf35dc90] [c0569e38] svc_rpcb_cleanup+0x18/0x30
  [cf35dca0] [c0198c5c] lockd_up+0x1dc/0x2e0
  [cf35dcd0] [c0195348] nlmclnt_init+0x2c/0xc8
  [cf35dcf0] [c015bb5c] nfs_start_lockd+0x98/0xec
  [cf35dd20] [c015ce6c] nfs_create_server+0x1e8/0x3f4
  [cf35dd90] [c0171590] nfs3_create_server+0x10/0x44
  [cf35dda0] [c016528c] nfs_try_mount+0x158/0x1e4
  [cf35de20] [c01670d0] nfs_fs_mount+0x434/0x8c8
  [cf35de70] [c00cd3bc] mount_fs+0x20/0xbc
  [cf35de90] [c00e4f88] vfs_kern_mount+0x50/0x104
  [cf35dec0] [c00e6e0c] do_mount+0x1d0/0x8e0
  [cf35df10] [c00e75ac] SyS_mount+0x90/0xd0
  [cf35df40] [c000ccf4] ret_from_syscall+0x0/0x3c

The addition of svc_shutdown_net() resulted in two calls to
svc_rpcb_cleanup(); the second is no longer necessary and crashes when
it calls rpcb_register_call with clnt=NULL.

Reported-by: Nikita Yushchenko <[email protected]>
Fixes: 679b033 "lockd: ensure we tear down any live sockets when socket creation fails during lockd_up"
Cc: [email protected]
Acked-by: Jeff Layton <[email protected]>
Signed-off-by: J. Bruce Fields <[email protected]>
alexander-zimmermann pushed a commit that referenced this pull request Nov 20, 2014
When unbinding imx-drm, the following oops was observed:

Unable to handle kernel NULL pointer dereference at virtual address 00000004
pgd = e995c000
[00000004] *pgd=4fea5831
Internal error: Oops: 817 [#1] SMP ARM
Modules linked in: bnep rfcomm bluetooth nfsd exportfs hid_cypress brcmfmac brcmutil snd_soc_fsl_ssi snd_soc_fsl_spdif imx_pcm_fiq imx_pcm_dma snd_soc_sgtl5000 imx_sdma imx2_wdt imx_ldb(C) imx_thermal snd_soc_imx_sgtl5000 snd_soc_imx_spdif snd_soc_imx_audmux
CPU: 1 PID: 779 Comm: bash Tainted: G         C    3.16.0-rc2+ #1230
task: ea9eb180 ti: ea378000 task.ti: ea378000
PC is at ipu_dp_put+0x10/0x18
LR is at ipu_plane_dpms+0x60/0x8c
pc : [<c0350d20>]    lr : [<c04bd9e8>]    psr: 200f0013
sp : ea379d80  ip : ea379d90  fp : ea379d8c
r10: 00100100  r9 : 00000000  r8 : 00200200
r7 : e9ba0264  r6 : e9ba01f8  r5 : 00000000  r4 : ea34b800
r3 : 00000000  r2 : 00000000  r1 : 0000009b  r0 : 00000000
Flags: nzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
Control: 10c53c7d  Table: 3995c04a  DAC: 00000015
Process bash (pid: 779, stack limit = 0xea378240)
Stack: (0xea379d80 to 0xea37a000)
...
Backtrace:
[<c0350d10>] (ipu_dp_put) from [<c04bd9e8>] (ipu_plane_dpms+0x60/0x8c)
[<c04bd988>] (ipu_plane_dpms) from [<c04bda40>] (ipu_disable_plane+0x2c/0x60)
[<c04bda14>] (ipu_disable_plane) from [<c04bda9c>] (ipu_plane_destroy+0x28/0x60)
[<c04bda74>] (ipu_plane_destroy) from [<c033ff84>] (drm_mode_config_cleanup+0x1b8/0x250)
[<c033fdcc>] (drm_mode_config_cleanup) from [<c04bc234>] (imx_drm_driver_unload+0x44/0x4c)
[<c04bc1f0>] (imx_drm_driver_unload) from [<c03394a4>] (drm_dev_unregister+0x2c/0xa0)
[<c0339478>] (drm_dev_unregister) from [<c0339f8c>] (drm_put_dev+0x30/0x6c)
[<c0339f5c>] (drm_put_dev) from [<c04bc1cc>] (imx_drm_unbind+0x14/0x18)
[<c04bc1b8>] (imx_drm_unbind) from [<c03530b4>] (component_master_del+0xbc/0xd8)
...
Code: e1a0c00d e92dd800 e24cb004 e3a03000 (e5c03004)

This is caused by a missing check in ipu_plane_dpms for a NULL pointer.

Fixes: b8d181e ("staging: drm/imx: add drm plane support")
Cc: <[email protected]>
Signed-off-by: Russell King <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
alexander-zimmermann pushed a commit that referenced this pull request Nov 20, 2014
When trying to unbind imx-drm, the following oops was observed from
the imx-ldb driver:

Unable to handle kernel NULL pointer dereference at virtual address 0000001c
pgd = de954000
[0000001c] *pgd=2e92c831, *pte=00000000, *ppte=00000000
Internal error: Oops: 17 [#1] SMP ARM
Modules linked in: bnep rfcomm bluetooth nfsd exportfs hid_cypress brcmfmac brcmutil snd_soc_fsl_ssi snd_soc_fsl_spdif imx_pcm_fiq imx_pcm_dma imx_ldb(C) imx_thermal imx_sdma imx2_wdt snd_soc_sgtl5000 snd_soc_imx_sgtl5000 snd_soc_imx_spdif snd_soc_imx_audmux
CPU: 1 PID: 1228 Comm: bash Tainted: G         C    3.16.0-rc2+ #1229
task: ea378d80 ti: de948000 task.ti: de948000
PC is at imx_ldb_unbind+0x1c/0x58 [imx_ldb]
LR is at component_unbind+0x38/0x70
pc : [<bf025068>]    lr : [<c0353108>]    psr: 200f0013
sp : de949da8  ip : de949dc0  fp : de949dbc
r10: e9a44b0c  r9 : 00000000  r8 : de949f78
r7 : 00000012  r6 : e9b3f400  r5 : e9b133b8  r4 : e9b13010
r3 : 00000000  r2 : e9b3f400  r1 : ea9a0210  r0 : e9b13020
Flags: nzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
Control: 10c53c7d  Table: 2e95404a  DAC: 00000015
Process bash (pid: 1228, stack limit = 0xde948240)
Stack: (0xde949da8 to 0xde94a000)
...
Backtrace:
[<bf02504c>] (imx_ldb_unbind [imx_ldb]) from [<c0353108>] (component_unbind+0x38/0x70)
[<c03530d0>] (component_unbind) from [<c03531d4>] (component_unbind_all+0x94/0xc8)
[<c0353140>] (component_unbind_all) from [<c04bc224>] (imx_drm_driver_unload+0x34/0x4c)
[<c04bc1f0>] (imx_drm_driver_unload) from [<c03394a4>] (drm_dev_unregister+0x2c/0xa0)
[<c0339478>] (drm_dev_unregister) from [<c0339f8c>] (drm_put_dev+0x30/0x6c)
[<c0339f5c>] (drm_put_dev) from [<c04bc1cc>] (imx_drm_unbind+0x14/0x18)
[<c04bc1b8>] (imx_drm_unbind) from [<c03530b4>] (component_master_del+0xbc/0xd8)
...
Code: e5904058 e2840010 e2845fea e59430a0 (e593301c)
---[ end trace 4f211c6dbbcd4963 ]---

This is caused by only having one channel out of the pair configured in
DT; the second channel remains uninitialised, but upon unbind, the
driver attempts to clean up both, thereby dereferencing a NULL pointer.
Avoid this by checking that the second channel is initialised.

Fixes: 1b3f767 ("imx-drm: initialise drm components directly")
Cc: <[email protected]>
Signed-off-by: Russell King <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
alexander-zimmermann pushed a commit that referenced this pull request Nov 20, 2014
This reverts commit 49a4bda.

Christoph reported an oops due to the above commit:

generic/089 242s ...[ 2187.041239] general protection fault: 0000 [#1]
SMP
[ 2187.042899] Modules linked in:
[ 2187.044000] CPU: 0 PID: 11913 Comm: kworker/0:1 Not tainted 3.16.0-rc6+ #1151
[ 2187.044287] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007
[ 2187.044287] Workqueue: nfsiod free_lock_state_work
[ 2187.044287] task: ffff880072b50cd0 ti: ffff88007a4ec000 task.ti: ffff88007a4ec000
[ 2187.044287] RIP: 0010:[<ffffffff81361ca6>]  [<ffffffff81361ca6>] free_lock_state_work+0x16/0x30
[ 2187.044287] RSP: 0018:ffff88007a4efd58  EFLAGS: 00010296
[ 2187.044287] RAX: 6b6b6b6b6b6b6b6b RBX: ffff88007a947ac0 RCX: 8000000000000000
[ 2187.044287] RDX: ffffffff826af9e0 RSI: ffff88007b093c00 RDI: ffff88007b093db8
[ 2187.044287] RBP: ffff88007a4efd58 R08: ffffffff832d3e10 R09: 000001c40efc0000
[ 2187.044287] R10: 0000000000000000 R11: 0000000000059e30 R12: ffff88007fc13240
[ 2187.044287] R13: ffff88007fc18b00 R14: ffff88007b093db8 R15: 0000000000000000
[ 2187.044287] FS:  0000000000000000(0000) GS:ffff88007fc00000(0000) knlGS:0000000000000000
[ 2187.044287] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[ 2187.044287] CR2: 00007f93ec33fb80 CR3: 0000000079dc2000 CR4: 00000000000006f0
[ 2187.044287] Stack:
[ 2187.044287]  ffff88007a4efdd8 ffffffff810cc877 ffffffff810cc80d ffff88007fc13258
[ 2187.044287]  000000007a947af0 0000000000000000 ffffffff8353ccc8 ffffffff82b6f3d0
[ 2187.044287]  0000000000000000 ffffffff82267679 ffff88007a4efdd8 ffff88007fc13240
[ 2187.044287] Call Trace:
[ 2187.044287]  [<ffffffff810cc877>] process_one_work+0x1c7/0x490
[ 2187.044287]  [<ffffffff810cc80d>] ? process_one_work+0x15d/0x490
[ 2187.044287]  [<ffffffff810cd569>] worker_thread+0x119/0x4f0
[ 2187.044287]  [<ffffffff810fbbad>] ? trace_hardirqs_on+0xd/0x10
[ 2187.044287]  [<ffffffff810cd450>] ? init_pwq+0x190/0x190
[ 2187.044287]  [<ffffffff810d3c6f>] kthread+0xdf/0x100
[ 2187.044287]  [<ffffffff810d3b90>] ? __init_kthread_worker+0x70/0x70
[ 2187.044287]  [<ffffffff81d9873c>] ret_from_fork+0x7c/0xb0
[ 2187.044287]  [<ffffffff810d3b90>] ? __init_kthread_worker+0x70/0x70
[ 2187.044287] Code: 0f 1f 44 00 00 31 c0 5d c3 66 66 66 2e 0f 1f 84 00 00 00 00 00 55 48 8d b7 48 fe ff ff 48 8b 87 58 fe ff ff 48 89 e5 48 8b 40 30 <48> 8b 00 48 8b 10 48 89 c7 48 8b 92 90 03 00 00 ff 52 28 5d c3
[ 2187.044287] RIP  [<ffffffff81361ca6>] free_lock_state_work+0x16/0x30
[ 2187.044287]  RSP <ffff88007a4efd58>
[ 2187.103626] ---[ end trace 0f11326d28e5d8fa ]---

The original reason for this patch was because the fl_release_private
operation couldn't sleep. With commit ed9814d (locks: defer freeing
locks in locks_delete_lock until after i_lock has been dropped), this is
no longer a problem so we can revert this patch.

Reported-by: Christoph Hellwig <[email protected]>
Signed-off-by: Jeff Layton <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
Tested-by: Christoph Hellwig <[email protected]>
Signed-off-by: Trond Myklebust <[email protected]>
alexander-zimmermann pushed a commit that referenced this pull request Nov 20, 2014
This fixes CVE-2014-3631.

It is possible for an associative array to end up with a shortcut node at the
root of the tree if there are more than fan-out leaves in the tree, but they
all crowd into the same slot in the lowest level (ie. they all have the same
first nibble of their index keys).

When assoc_array_gc() returns back up the tree after scanning some leaves, it
can fall off of the root and crash because it assumes that the back pointer
from a shortcut (after label ascend_old_tree) must point to a normal node -
which isn't true of a shortcut node at the root.

Should we find we're ascending rootwards over a shortcut, we should check to
see if the backpointer is zero - and if it is, we have completed the scan.

This particular bug cannot occur if the root node is not a shortcut - ie. if
you have fewer than 17 keys in a keyring or if you have at least two keys that
sit into separate slots (eg. a keyring and a non keyring).

This can be reproduced by:

	ring=`keyctl newring bar @s`
	for ((i=1; i<=18; i++)); do last_key=`keyctl newring foo$i $ring`; done
	keyctl timeout $last_key 2

Doing this:

	echo 3 >/proc/sys/kernel/keys/gc_delay

first will speed things up.

If we do fall off of the top of the tree, we get the following oops:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000018
IP: [<ffffffff8136cea7>] assoc_array_gc+0x2f7/0x540
PGD dae15067 PUD cfc24067 PMD 0
Oops: 0000 [#1] SMP
Modules linked in: xt_nat xt_mark nf_conntrack_netbios_ns nf_conntrack_broadcast ip6t_rpfilter ip6t_REJECT xt_conntrack ebtable_nat ebtable_broute bridge stp llc ebtable_filter ebtables ip6table_ni
CPU: 0 PID: 26011 Comm: kworker/0:1 Not tainted 3.14.9-200.fc20.x86_64 #1
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
Workqueue: events key_garbage_collector
task: ffff8800918bd580 ti: ffff8800aac14000 task.ti: ffff8800aac14000
RIP: 0010:[<ffffffff8136cea7>] [<ffffffff8136cea7>] assoc_array_gc+0x2f7/0x540
RSP: 0018:ffff8800aac15d40  EFLAGS: 00010206
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff8800aaecacc0
RDX: ffff8800daecf440 RSI: 0000000000000001 RDI: ffff8800aadc2bc0
RBP: ffff8800aac15da8 R08: 0000000000000001 R09: 0000000000000003
R10: ffffffff8136ccc7 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000070 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff88011fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 0000000000000018 CR3: 00000000db10d000 CR4: 00000000000006f0
Stack:
 ffff8800aac15d50 0000000000000011 ffff8800aac15db8 ffffffff812e2a70
 ffff880091a00600 0000000000000000 ffff8800aadc2bc3 00000000cd42c987
 ffff88003702df20 ffff88003702dfa0 0000000053b65c09 ffff8800aac15fd8
Call Trace:
 [<ffffffff812e2a70>] ? keyring_detect_cycle_iterator+0x30/0x30
 [<ffffffff812e3e75>] keyring_gc+0x75/0x80
 [<ffffffff812e1424>] key_garbage_collector+0x154/0x3c0
 [<ffffffff810a67b6>] process_one_work+0x176/0x430
 [<ffffffff810a744b>] worker_thread+0x11b/0x3a0
 [<ffffffff810a7330>] ? rescuer_thread+0x3b0/0x3b0
 [<ffffffff810ae1a8>] kthread+0xd8/0xf0
 [<ffffffff810ae0d0>] ? insert_kthread_work+0x40/0x40
 [<ffffffff816ffb7c>] ret_from_fork+0x7c/0xb0
 [<ffffffff810ae0d0>] ? insert_kthread_work+0x40/0x40
Code: 08 4c 8b 22 0f 84 bf 00 00 00 41 83 c7 01 49 83 e4 fc 41 83 ff 0f 4c 89 65 c0 0f 8f 5a fe ff ff 48 8b 45 c0 4d 63 cf 49 83 c1 02 <4e> 8b 34 c8 4d 85 f6 0f 84 be 00 00 00 41 f6 c6 01 0f 84 92
RIP  [<ffffffff8136cea7>] assoc_array_gc+0x2f7/0x540
 RSP <ffff8800aac15d40>
CR2: 0000000000000018
---[ end trace 1129028a088c0cbd ]---

Signed-off-by: David Howells <[email protected]>
Acked-by: Don Zickus <[email protected]>
Signed-off-by: James Morris <[email protected]>
alexander-zimmermann pushed a commit that referenced this pull request Nov 20, 2014
The problem is that the slave is first linked and slave_cnt is
incremented afterwards leading to a div by zero in the modes that use it
as a modulus. What happens is that in bond_start_xmit()
bond_has_slaves() is used to evaluate further transmission and it becomes
true after the slave is linked in, but when slave_cnt is used in the xmit
path it is still 0, so fetch it once and transmit based on that. Since
it is used only in round-robin and XOR modes, the fix is only for them.
Thanks to Eric Dumazet for pointing out the fault in my first try to fix
this.

Call trace (took it out of net-next kernel, but it's the same with net):
[46934.330038] divide error: 0000 [#1] SMP
[46934.330041] Modules linked in: bonding(O) 9p fscache
snd_hda_codec_generic crct10dif_pclmul
[46934.330041] bond0: Enslaving eth1 as an active interface with an up
link
[46934.330051]  ppdev joydev crc32_pclmul crc32c_intel 9pnet_virtio
ghash_clmulni_intel snd_hda_intel 9pnet snd_hda_controller parport_pc
serio_raw pcspkr snd_hda_codec parport virtio_balloon virtio_console
snd_hwdep snd_pcm pvpanic i2c_piix4 snd_timer i2ccore snd soundcore
virtio_blk virtio_net virtio_pci virtio_ring virtio ata_generic
pata_acpi floppy [last unloaded: bonding]
[46934.330053] CPU: 1 PID: 3382 Comm: ping Tainted: G           O
3.17.0-rc4+ torvalds#27
[46934.330053] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[46934.330054] task: ffff88005aebf2c0 ti: ffff88005b728000 task.ti:
ffff88005b728000
[46934.330059] RIP: 0010:[<ffffffffa0198c33>]  [<ffffffffa0198c33>]
bond_start_xmit+0x1c3/0x450 [bonding]
[46934.330060] RSP: 0018:ffff88005b72b7f8  EFLAGS: 00010246
[46934.330060] RAX: 0000000000000679 RBX: ffff88004b077000 RCX:
000000000000002a
[46934.330061] RDX: 0000000000000000 RSI: ffff88004b3f0500 RDI:
ffff88004b077940
[46934.330061] RBP: ffff88005b72b830 R08: 00000000000000c0 R09:
ffff88004a83e000
[46934.330062] R10: 000000000000ffff R11: ffff88004b1f12c0 R12:
ffff88004b3f0500
[46934.330062] R13: ffff88004b3f0500 R14: 000000000000002a R15:
ffff88004b077940
[46934.330063] FS:  00007fbd91a4c740(0000) GS:ffff88005f080000(0000)
knlGS:0000000000000000
[46934.330064] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[46934.330064] CR2: 00007f803a8bb000 CR3: 000000004b2c9000 CR4:
00000000000406e0
[46934.330069] Stack:
[46934.330071]  ffffffff811e6169 00000000e772fa05 ffff88004b077000
ffff88004b3f0500
[46934.330072]  ffffffff81d17d18 000000000000002a 0000000000000000
ffff88005b72b8a0
[46934.330073]  ffffffff81620108 ffffffff8161fe0e ffff88005b72b8c4
ffff88005b302000
[46934.330073] Call Trace:
[46934.330077]  [<ffffffff811e6169>] ?
__kmalloc_node_track_caller+0x119/0x300
[46934.330084]  [<ffffffff81620108>] dev_hard_start_xmit+0x188/0x410
[46934.330086]  [<ffffffff8161fe0e>] ? harmonize_features+0x2e/0x90
[46934.330088]  [<ffffffff81620b06>] __dev_queue_xmit+0x456/0x590
[46934.330089]  [<ffffffff81620c50>] dev_queue_xmit+0x10/0x20
[46934.330090]  [<ffffffff8168f022>] arp_xmit+0x22/0x60
[46934.330091]  [<ffffffff8168f090>] arp_send.part.16+0x30/0x40
[46934.330092]  [<ffffffff8168f1e5>] arp_solicit+0x115/0x2b0
[46934.330094]  [<ffffffff8160b5d7>] ? copy_skb_header+0x17/0xa0
[46934.330096]  [<ffffffff8162875a>] neigh_probe+0x4a/0x70
[46934.330097]  [<ffffffff8162979c>] __neigh_event_send+0xac/0x230
[46934.330098]  [<ffffffff8162a00b>] neigh_resolve_output+0x13b/0x220
[46934.330100]  [<ffffffff8165f120>] ? ip_forward_options+0x1c0/0x1c0
[46934.330101]  [<ffffffff81660478>] ip_finish_output+0x1f8/0x860
[46934.330102]  [<ffffffff81661f08>] ip_output+0x58/0x90
[46934.330103]  [<ffffffff81661602>] ? __ip_local_out+0xa2/0xb0
[46934.330104]  [<ffffffff81661640>] ip_local_out_sk+0x30/0x40
[46934.330105]  [<ffffffff81662a66>] ip_send_skb+0x16/0x50
[46934.330106]  [<ffffffff81662ad3>] ip_push_pending_frames+0x33/0x40
[46934.330107]  [<ffffffff8168854c>] raw_sendmsg+0x88c/0xa30
[46934.330110]  [<ffffffff81612b31>] ? skb_recv_datagram+0x41/0x60
[46934.330111]  [<ffffffff816875a9>] ? raw_recvmsg+0xa9/0x1f0
[46934.330113]  [<ffffffff816978d4>] inet_sendmsg+0x74/0xc0
[46934.330114]  [<ffffffff81697a9b>] ? inet_recvmsg+0x8b/0xb0
[46934.330115] bond0: Adding slave eth2
[46934.330116]  [<ffffffff8160357c>] sock_sendmsg+0x9c/0xe0
[46934.330118]  [<ffffffff81603248>] ?
move_addr_to_kernel.part.20+0x28/0x80
[46934.330121]  [<ffffffff811b4477>] ? might_fault+0x47/0x50
[46934.330122]  [<ffffffff816039b9>] ___sys_sendmsg+0x3a9/0x3c0
[46934.330125]  [<ffffffff8144a14a>] ? n_tty_write+0x3aa/0x530
[46934.330127]  [<ffffffff810d1ae4>] ? __wake_up+0x44/0x50
[46934.330129]  [<ffffffff81242b38>] ? fsnotify+0x238/0x310
[46934.330130]  [<ffffffff816048a1>] __sys_sendmsg+0x51/0x90
[46934.330131]  [<ffffffff816048f2>] SyS_sendmsg+0x12/0x20
[46934.330134]  [<ffffffff81738b29>] system_call_fastpath+0x16/0x1b
[46934.330144] Code: 48 8b 10 4c 89 ee 4c 89 ff e8 aa bc ff ff 31 c0 e9
1a ff ff ff 0f 1f 00 4c 89 ee 4c 89 ff e8 65 fb ff ff 31 d2 4c 89 ee 4c
89 ff <f7> b3 64 09 00 00 e8 02 bd ff ff 31 c0 e9 f2 fe ff ff 0f 1f 00
[46934.330146] RIP  [<ffffffffa0198c33>] bond_start_xmit+0x1c3/0x450
[bonding]
[46934.330146]  RSP <ffff88005b72b7f8>

CC: Eric Dumazet <[email protected]>
CC: Andy Gospodarek <[email protected]>
CC: Jay Vosburgh <[email protected]>
CC: Veaceslav Falico <[email protected]>
Fixes: 278b208 ("bonding: initial RCU conversion")
Signed-off-by: Nikolay Aleksandrov <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
alexander-zimmermann pushed a commit that referenced this pull request Nov 20, 2014
In rare cases under heavy VMA pressure the ref count for a fscache cookie
becomes corrupt. In this case we decrement ref count even if we fail before
incrementing the refcount.

FS-Cache: Assertion failed bnode-eca5f9c6/syslog
0 > 0 is false
------------[ cut here ]------------
kernel BUG at fs/fscache/cookie.c:519!
invalid opcode: 0000 [#1] SMP
Call Trace:
[<ffffffffa01ba060>] __fscache_relinquish_cookie+0x50/0x220 [fscache]
[<ffffffffa02d64ce>] ceph_fscache_unregister_inode_cookie+0x3e/0x50 [ceph]
[<ffffffffa02ae1d3>] ceph_destroy_inode+0x33/0x200 [ceph]
[<ffffffff811cf67e>] ? __fsnotify_inode_delete+0xe/0x10
[<ffffffff811a9e0c>] destroy_inode+0x3c/0x70
[<ffffffff811a9f51>] evict+0x111/0x180
[<ffffffff811aa763>] iput+0x103/0x190
[<ffffffff811a5de8>] __dentry_kill+0x1c8/0x220
[<ffffffff811a5f31>] shrink_dentry_list+0xf1/0x250
[<ffffffff811a762c>] prune_dcache_sb+0x4c/0x60
[<ffffffff811930af>] super_cache_scan+0xff/0x170
[<ffffffff8113d7a0>] shrink_slab_node+0x140/0x2c0
[<ffffffff8113f2da>] shrink_slab+0x8a/0x130
[<ffffffff81142572>] balance_pgdat+0x3e2/0x5d0
[<ffffffff811428ca>] kswapd+0x16a/0x4a0
[<ffffffff810a43f0>] ? __wake_up_sync+0x20/0x20
[<ffffffff81142760>] ? balance_pgdat+0x5d0/0x5d0
[<ffffffff81083e09>] kthread+0xc9/0xe0
[<ffffffff81010000>] ? ftrace_raw_event_xen_mmu_release_ptpage+0x70/0x90
[<ffffffff81083d40>] ? flush_kthread_worker+0xb0/0xb0
[<ffffffff8159f63c>] ret_from_fork+0x7c/0xb0
[<ffffffff81083d40>] ? flush_kthread_worker+0xb0/0xb0
RIP [<ffffffffa01b984b>] __fscache_disable_cookie+0x1db/0x210 [fscache]
RSP <ffff8803bc85f9b8>
---[ end trace 254d0d7c74a01f25 ]---

Signed-off-by: Milosz Tanski <[email protected]>
Signed-off-by: David Howells <[email protected]>
alexander-zimmermann pushed a commit that referenced this pull request Nov 20, 2014
This reverts commit fc1b253 ("PCI: Don't scan random busses in
pci_scan_bridge()") because it breaks CardBus on some machines.

David tested a Dell Latitude D505 that worked like this prior to
fc1b253:

    pci 0000:00:1e.0: PCI bridge to [bus 01]
    pci 0000:01:01.0: CardBus bridge to [bus 02-05]

Note that the 01:01.0 CardBus bridge has a bus number aperture of
[bus 02-05], but those buses are all outside the 00:1e.0 PCI bridge bus
number aperture, so accesses to buses 02-05 never reach CardBus.  This is
later patched up by yenta_fixup_parent_bridge(), which changes the
subordinate bus number of the 00:1e.0 PCI bridge:

    pci_bus 0000:01: Raising subordinate bus# of parent bus (#1) from #1 to #05

With fc1b253, pci_scan_bridge() fails immediately when it notices that
we can't allocate a valid secondary bus number for the CardBus bridge, and
CardBus doesn't work at all:

    pci 0000:01:01.0: can't allocate child bus 01 from [bus 01]

I'd prefer to fix this by integrating the yenta_fixup_parent_bridge() logic
into pci_scan_bridge() so we fix the bus number apertures up front.  But
I don't think we can do that before v3.17, so I'm going to revert this to
avoid the problem while we're working on the long-term fix.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=83441
Link: http://lkml.kernel.org/r/[email protected]
Reported-by: David Henningsson <[email protected]>
Tested-by: David Henningsson <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
CC: [email protected]	# v3.15+
alexander-zimmermann pushed a commit that referenced this pull request Nov 20, 2014
…om_pages

sg_alloc_table_from_pages() only allocates a sg_table, so it should just use
GFP_KERNEL, not gfp_flags. If gfp_flags contains __GFP_DMA32 then mm/sl[au]b.c
will call BUG_ON:

[  358.027515] ------------[ cut here ]------------
[  358.027546] kernel BUG at mm/slub.c:1416!
[  358.027558] invalid opcode: 0000 [#1] PREEMPT SMP
[  358.027576] Modules linked in: mt2131 s5h1409 tda8290 tuner cx25840 cx23885 btcx_risc altera_ci tda18271 altera_stapl videobuf2_dvb tveeprom cx2341x videobuf2_dma_sg dvb_core rc_core videobuf2_memops videobuf2_core nouveau zr36067 videocodec v4l2_common videodev media x86_pkg_temp_thermal cfbfillrect cfbimgblt cfbcopyarea ttm drm_kms_helper processor button isci
[  358.027712] CPU: 19 PID: 3654 Comm: cat Not tainted 3.16.0-rc6-telek torvalds#167
[  358.027723] Hardware name: ASUSTeK COMPUTER INC. Z9PE-D8 WS/Z9PE-D8 WS, BIOS 5404 02/10/2014
[  358.027741] task: ffff880897c7d960 ti: ffff88089b4d4000 task.ti: ffff88089b4d4000
[  358.027753] RIP: 0010:[<ffffffff81196040>]  [<ffffffff81196040>] new_slab+0x280/0x320
[  358.027776] RSP: 0018:ffff88089b4d7ae8  EFLAGS: 00010002
[  358.027787] RAX: ffff880897c7d960 RBX: 0000000000000000 RCX: ffff88089b4d7b50
[  358.027798] RDX: 00000000ffffffff RSI: 0000000000000004 RDI: ffff88089f803b00
[  358.027809] RBP: ffff88089b4d7bb8 R08: 0000000000000000 R09: 0000000100400040
[  358.027821] R10: 0000160000000000 R11: ffff88109bc02c40 R12: 0000000000000001
[  358.027832] R13: ffff88089f8000c0 R14: ffff88089f803b00 R15: ffff8810bfcf4be0
[  358.027845] FS:  00007f83fe5c0700(0000) GS:ffff8810bfce0000(0000) knlGS:0000000000000000
[  358.027858] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  358.027868] CR2: 0000000001dfd568 CR3: 0000001097d5a000 CR4: 00000000000407e0
[  358.027878] Stack:
[  358.027885]  ffffffff81198860 ffff8810bfcf4be0 ffff880897c7d960 0000000000001b00
[  358.027905]  ffff880897c7d960 0000000000000000 ffff8810bfcf4bf0 0000000000000000
[  358.027924]  0000000000000000 0000000100000100 ffffffff813ef84a 00000004ffffffff
[  358.027944] Call Trace:
[  358.027956]  [<ffffffff81198860>] ? __slab_alloc+0x400/0x4e0
[  358.027973]  [<ffffffff813ef84a>] ? sg_kmalloc+0x1a/0x30
[  358.027985]  [<ffffffff81198f17>] __kmalloc+0x127/0x150
[  358.027997]  [<ffffffff813ef84a>] ? sg_kmalloc+0x1a/0x30
[  358.028009]  [<ffffffff813ef84a>] sg_kmalloc+0x1a/0x30
[  358.028023]  [<ffffffff813eff84>] __sg_alloc_table+0x74/0x180
[  358.028035]  [<ffffffff813ef830>] ? sg_kfree+0x20/0x20
[  358.028048]  [<ffffffff813f00af>] sg_alloc_table+0x1f/0x60
[  358.028061]  [<ffffffff813f0174>] sg_alloc_table_from_pages+0x84/0x1f0
[  358.028077]  [<ffffffffa007c3f9>] vb2_dma_sg_alloc+0x159/0x230 [videobuf2_dma_sg]
[  358.028095]  [<ffffffffa003d55a>] __vb2_queue_alloc+0x10a/0x680 [videobuf2_core]
[  358.028113]  [<ffffffffa003e110>] __reqbufs.isra.14+0x220/0x3e0 [videobuf2_core]
[  358.028130]  [<ffffffffa003e79d>] __vb2_init_fileio+0xbd/0x380 [videobuf2_core]
[  358.028147]  [<ffffffffa003f563>] __vb2_perform_fileio+0x5b3/0x6e0 [videobuf2_core]
[  358.028164]  [<ffffffffa003f871>] vb2_fop_read+0xb1/0x100 [videobuf2_core]
[  358.028184]  [<ffffffffa06dd2e5>] v4l2_read+0x65/0xb0 [videodev]
[  358.028198]  [<ffffffff811a243f>] vfs_read+0x8f/0x170
[  358.028210]  [<ffffffff811a30a1>] SyS_read+0x41/0xb0
[  358.028224]  [<ffffffff818f02e9>] system_call_fastpath+0x16/0x1b
[  358.028234] Code: 66 90 e9 dc fd ff ff 0f 1f 40 00 41 8b 4d 68 e9 d5 fe ff ff 0f 1f 80 00 00 00 00 f0 41 80 4d 00 40 e9 03 ff ff ff 0f 1f 44 00 00 <0f> 0b 66 0f 1f 44 00 00 44 89 c6 4c 89 45 d0 e8 0c 82 ff ff 48
[  358.028415] RIP  [<ffffffff81196040>] new_slab+0x280/0x320
[  358.028432]  RSP <ffff88089b4d7ae8>
[  358.032208] ---[ end trace 6443240199c706e4 ]---

Signed-off-by: Hans Verkuil <[email protected]>
Cc: [email protected]      # for v3.13 and up
Acked-by: Marek Szyprowski <[email protected]>
Signed-off-by: Mauro Carvalho Chehab <[email protected]>
alexander-zimmermann pushed a commit that referenced this pull request Nov 20, 2014
When I try to set the TV standard to e.g. PAL on my Hauppauge WinTV-HVR3000 I get
the following oops:

 9464.262345] CX24123: detected CX24123
[ 9464.262526] BUG: unable to handle kernel NULL pointer dereference at 0000000000000230
[ 9464.262555] IP: [<ffffffff816676b5>] acpi_i2c_install_space_handler+0x15/0xc0
[ 9464.262576] PGD 0
[ 9464.262584] Oops: 0000 [#1] PREEMPT SMP
[ 9464.262597] Modules linked in: cx24123 cx22702 cx88_dvb(+) videobuf_dvb cx88_vp3054_i2c cx88_blackbird cx8802 ir_lirc_codec ir_xmp_decoder ir_sanyo_decoder ir_jvc_decoder ir_mce_kbd_decoder ir_sharp_decoder lirc_dev ir_sony_decoder ir_rc6_decoder ir_nec_decoder ir_rc5_decoder rc_hauppauge wm8775 tuner_simple tuner_types tda9887 cx8800 cx88xx btcx_risc videobuf_dma_sg videobuf_core mt2131 s5h1409 tda8290 tuner cx25840 cx23885 altera_ci tda18271 altera_stapl videobuf2_dvb tveeprom cx2341x videobuf2_dma_sg dvb_core rc_core videobuf2_memops videobuf2_core v4l2_common videodev media nouveau x86_pkg_temp_thermal cfbfillrect cfbimgblt cfbcopyarea ttm drm_kms_helper processor button isci
[ 9464.262786] CPU: 2 PID: 2417 Comm: modprobe Not tainted 3.17.0-rc1-telek torvalds#322
[ 9464.262796] Hardware name: ASUSTeK COMPUTER INC. Z9PE-D8 WS/Z9PE-D8 WS, BIOS 5404 02/10/2014
[ 9464.262807] task: ffff881097959ad0 ti: ffff88109967c000 task.ti: ffff88109967c000
[ 9464.262817] RIP: 0010:[<ffffffff816676b5>]  [<ffffffff816676b5>] acpi_i2c_install_space_handler+0x15/0xc0
[ 9464.262834] RSP: 0018:ffff88109967fbd8  EFLAGS: 00010246
[ 9464.262843] RAX: 0000000000000000 RBX: ffff880892a89540 RCX: 0000000000000000
[ 9464.262853] RDX: 0000000080000001 RSI: ffff880892e75870 RDI: ffff880892a89540
[ 9464.262862] RBP: ffff88109967fbf8 R08: ffff881099b2ccc0 R09: ffff880891efa088
[ 9464.262872] R10: 0000000000000000 R11: 0000000000000022 R12: 0000000000000000
[ 9464.262883] R13: ffff880892a895b0 R14: 00000000ffffffed R15: ffff88089b48f800
[ 9464.262893] FS:  00007fe42b6d7700(0000) GS:ffff88089fc40000(0000) knlGS:0000000000000000
[ 9464.262904] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 9464.262912] CR2: 0000000000000230 CR3: 0000001094078000 CR4: 00000000000407e0
[ 9464.262922] Stack:
[ 9464.262927]  ffff880892a89540 0000000000000000 ffff880892a895b0 ffff88109a155a80
[ 9464.262944]  ffff88109967fc20 ffffffff81666a36 0000000000000020 ffff880892a89540
[ 9464.262960]  ffffffffa01c8d40 ffff88109967fc40 ffffffff81666c67 ffff880892a89000
[ 9464.262977] Call Trace:
[ 9464.262987]  [<ffffffff81666a36>] i2c_register_adapter+0x166/0x340
[ 9464.262998]  [<ffffffff81666c67>] i2c_add_adapter+0x57/0x60
[ 9464.263011]  [<ffffffffa01e2c58>] cx24123_attach+0x108/0x1ba [cx24123]
[ 9464.263025]  [<ffffffffa01c5a76>] dvb_register+0x404/0x245b [cx88_dvb]
[ 9464.263039]  [<ffffffffa0059183>] ? videobuf_queue_core_init+0xe3/0x140 [videobuf_core]
[ 9464.263052]  [<ffffffffa01c54b1>] cx8802_dvb_probe+0x1e1/0x261 [cx88_dvb]
[ 9464.263066]  [<ffffffffa01a3b00>] cx8802_register_driver+0x190/0x20d [cx8802]
[ 9464.263077]  [<ffffffffa01cc000>] ? 0xffffffffa01cc000
[ 9464.263089]  [<ffffffffa01cc025>] dvb_init+0x25/0x27 [cx88_dvb]
[ 9464.263101]  [<ffffffff810002c4>] do_one_initcall+0x84/0x1c0
[ 9464.263113]  [<ffffffff811893fa>] ? __vunmap+0x9a/0x100
[ 9464.263125]  [<ffffffff81122a66>] load_module+0x1216/0x1790
[ 9464.263134]  [<ffffffff8111ff70>] ? __symbol_put+0x70/0x70
[ 9464.263145]  [<ffffffff811aa8cc>] ? vfs_read+0x11c/0x170
[ 9464.263156]  [<ffffffff811201d9>] ? copy_module_from_fd.isra.53+0x119/0x170
[ 9464.263168]  [<ffffffff81123116>] SyS_finit_module+0x76/0x80
[ 9464.263181]  [<ffffffff818d19e9>] system_call_fastpath+0x16/0x1b
[ 9464.263190] Code: 81 31 c0 e8 2e f6 e8 ff 48 83 c4 08 5b 5d eb de 66 0f 1f 44 00 00 55 48 89 e5 41 56 41 55 41 54 53 41 be ed ff ff ff 48 8b 47 70 <48> 8b 80 30 02 00 00 48 85 c0 74 58 4c 8b 68 08 4d 85 ed 74 4f
[ 9464.263347] RIP  [<ffffffff816676b5>] acpi_i2c_install_space_handler+0x15/0xc0
[ 9464.263361]  RSP <ffff88109967fbd8>
[ 9464.263367] CR2: 0000000000000230
[ 9464.266919] ---[ end trace 57fd490bdb72e733 ]---

I traced this to a NULL i2c_adapter parent pointer when cx24123 creates its own
i2c adapter. The acpi_i2c_install_space_handler function appeared in 3.17, so
that's probably why this hasn't been seen before.

Signed-off-by: Hans Verkuil <[email protected]>
Signed-off-by: Mauro Carvalho Chehab <[email protected]>
alexander-zimmermann pushed a commit that referenced this pull request Nov 20, 2014
While debugging a cpufreq-related hardware failure on a system I saw the
following lockdep warning:

 =========================
 [ BUG: held lock freed! ] 3.17.0-rc4+ #1 Tainted: G            E
 -------------------------
 insmod/2247 is freeing memory ffff88006e1b1400-ffff88006e1b17ff, with a lock still held there!
  (&policy->rwsem){+.+...}, at: [<ffffffff8156d37d>] __cpufreq_add_dev.isra.21+0x47d/0xb80
 3 locks held by insmod/2247:
  #0:  (subsys mutex#5){+.+.+.}, at: [<ffffffff81485579>] subsys_interface_register+0x69/0x120
  #1:  (cpufreq_rwsem){.+.+.+}, at: [<ffffffff8156cf73>] __cpufreq_add_dev.isra.21+0x73/0xb80
  #2:  (&policy->rwsem){+.+...}, at: [<ffffffff8156d37d>] __cpufreq_add_dev.isra.21+0x47d/0xb80

 stack backtrace:
 CPU: 0 PID: 2247 Comm: insmod Tainted: G            E  3.17.0-rc4+ #1
 Hardware name: HP ProLiant MicroServer Gen8, BIOS J06 08/24/2013
  0000000000000000 000000008f3063c4 ffff88006f87bb30 ffffffff8171b358
  ffff88006bcf3750 ffff88006f87bb68 ffffffff810e09e1 ffff88006e1b1400
  ffffea0001b86c00 ffffffff8156d327 ffff880073003500 0000000000000246
 Call Trace:
  [<ffffffff8171b358>] dump_stack+0x4d/0x66
  [<ffffffff810e09e1>] debug_check_no_locks_freed+0x171/0x180
  [<ffffffff8156d327>] ? __cpufreq_add_dev.isra.21+0x427/0xb80
  [<ffffffff8121412b>] kfree+0xab/0x2b0
  [<ffffffff8156d327>] __cpufreq_add_dev.isra.21+0x427/0xb80
  [<ffffffff81724cf7>] ? _raw_spin_unlock+0x27/0x40
  [<ffffffffa003517f>] ? pcc_cpufreq_do_osc+0x17f/0x17f [pcc_cpufreq]
  [<ffffffff8156da8e>] cpufreq_add_dev+0xe/0x10
  [<ffffffff814855d1>] subsys_interface_register+0xc1/0x120
  [<ffffffff8156bcf2>] cpufreq_register_driver+0x112/0x340
  [<ffffffff8121415a>] ? kfree+0xda/0x2b0
  [<ffffffffa003517f>] ? pcc_cpufreq_do_osc+0x17f/0x17f [pcc_cpufreq]
  [<ffffffffa003562e>] pcc_cpufreq_init+0x4af/0xe81 [pcc_cpufreq]
  [<ffffffffa003517f>] ? pcc_cpufreq_do_osc+0x17f/0x17f [pcc_cpufreq]
  [<ffffffff81002144>] do_one_initcall+0xd4/0x210
  [<ffffffff811f7472>] ? __vunmap+0xd2/0x120
  [<ffffffff81127155>] load_module+0x1315/0x1b70
  [<ffffffff811222a0>] ? store_uevent+0x70/0x70
  [<ffffffff811229d9>] ? copy_module_from_fd.isra.44+0x129/0x180
  [<ffffffff81127b86>] SyS_finit_module+0xa6/0xd0
  [<ffffffff81725b69>] system_call_fastpath+0x16/0x1b
 cpufreq: __cpufreq_add_dev: ->get() failed
insmod: ERROR: could not insert module pcc-cpufreq.ko: No such device

The warning occurs in the __cpufreq_add_dev() code which does

        down_write(&policy->rwsem);
	...
        if (cpufreq_driver->get && !cpufreq_driver->setpolicy) {
                policy->cur = cpufreq_driver->get(policy->cpu);
                if (!policy->cur) {
                        pr_err("%s: ->get() failed\n", __func__);
                        goto err_get_freq;
                }

If cpufreq_driver->get(policy->cpu) returns an error we execute the
code at err_get_freq, which does not up the policy->rwsem.  This causes
the lockdep warning.

Trivial patch to up the policy->rwsem in the error path.

After the patch has been applied, and an error occurs in the
cpufreq_driver->get(policy->cpu) call we will now see

cpufreq: __cpufreq_add_dev: ->get() failed
cpufreq: __cpufreq_add_dev: ->get() failed
modprobe: ERROR: could not insert 'pcc_cpufreq': No such device

Fixes: 4e97b63 (cpufreq: Initialize governor for a new policy under policy->rwsem)
Signed-off-by: Prarit Bhargava <[email protected]>
Acked-by: Viresh Kumar <[email protected]>
Cc: 3.14+ <[email protected]> # 3.14+
Signed-off-by: Rafael J. Wysocki <[email protected]>
alexander-zimmermann pushed a commit that referenced this pull request Nov 20, 2014
…sp_free()"

Revert commit 6efde38 (PM / Hibernate: Iterate over set bits
instead of PFNs in swsusp_free()) that introduced a NULL pointer
dereference during system resume from hibernation:

BUG: unable to handle kernel NULL pointer dereference at (null)
IP: [<ffffffff810a8cc1>] swsusp_free+0x21/0x190
PGD b39c2067 PUD b39c1067 PMD 0
Oops: 0000 [#1] SMP
Modules linked in: <irrelevant list of modules>
CPU: 1 PID: 4898 Comm: s2disk Tainted: G         C     3.17-rc5-amd64 #1 Debian 3.17~rc5-1~exp1
Hardware name: LENOVO 2776LEG/2776LEG, BIOS 6EET55WW (3.15 ) 12/19/2011
task: ffff88023155ea40 ti: ffff8800b3b14000 task.ti: ffff8800b3b14000
RIP: 0010:[<ffffffff810a8cc1>]  [<ffffffff810a8cc1>]
swsusp_free+0x21/0x190
RSP: 0018:ffff8800b3b17ea8  EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff8800b39bab00 RCX: 0000000000000001
RDX: ffff8800b39bab10 RSI: ffff8800b39bab00 RDI: 0000000000000000
RBP: 0000000000000010 R08: 0000000000000000 R09: 0000000000000000
R10: ffff8800b39bab10 R11: 0000000000000246 R12: ffffea0000000000
R13: ffff880232f485a0 R14: ffff88023ac27cd8 R15: ffff880232927590
FS:  00007f406d83b700(0000) GS:ffff88023bc80000(0000)
knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 0000000000000000 CR3: 00000000b3a62000 CR4: 00000000000007e0
Stack:
 ffff8800b39bab00 0000000000000010 ffff880232927590 ffffffff810acb4a
 ffff8800b39bab00 ffffffff811a955a ffff8800b39bab10 0000000000000000
 ffff88023155f098 ffffffff81a6b8c0 ffff88023155ea40 0000000000000007
Call Trace:
 [<ffffffff810acb4a>] ? snapshot_release+0x2a/0xb0
 [<ffffffff811a955a>] ? __fput+0xca/0x1d0
 [<ffffffff81080627>] ? task_work_run+0x97/0xd0
 [<ffffffff81012d89>] ? do_notify_resume+0x69/0xa0
 [<ffffffff8151452a>] ? int_signal+0x12/0x17
Code: 66 2e 0f 1f 84 00 00 00 00 00 66 66 66 66 90 41 54 48 8b 05 ba 62 9c 00 49 bc 00 00 00 00 00 ea ff ff 48 8b 3d a1 62 9c 00 55 53 <48> 8b 10 48 89 50 18 48 8b 52 20 48 c7 40 28 00 00 00 00 c7 40
RIP  [<ffffffff810a8cc1>] swsusp_free+0x21/0x190
 RSP <ffff8800b3b17ea8>
CR2: 0000000000000000
---[ end trace f02be86a1ec0cccb ]---

due to forbidden_pages_map being NULL in swsusp_free().

Fixes: 6efde38 "PM / Hibernate: Iterate over set bits instead of PFNs in swsusp_free()"
Reported-by: Bjørn Mork <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>
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