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Support restoring B/C OA counter config in RC6 WA BB #4

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rib opened this issue Jan 14, 2016 · 0 comments
Open

Support restoring B/C OA counter config in RC6 WA BB #4

rib opened this issue Jan 14, 2016 · 0 comments

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@rib
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rib commented Jan 14, 2016

So we can aim to leave RC6 enabled while capturing OA metrics, the i915 perf driver needs to support adding the the B/C counter configuration to the RC6 Workaround Batch Buffer.

Note: Gen 9 has an Errata where the RC6 WA BB is not always being executed, whereby the MUX config won't be restored. Userspace may need to be involved in recognising when the metrics configuration isn't correctly restored and request a re-configuration.

rib pushed a commit that referenced this issue Feb 22, 2016
Fixes segmentation fault using, for instance:

  (gdb) run record -I -e intel_pt/tsc=1,noretcomp=1/u /bin/ls
  Starting program: /home/acme/bin/perf record -I -e intel_pt/tsc=1,noretcomp=1/u /bin/ls
  Missing separate debuginfos, use: dnf debuginfo-install glibc-2.22-7.fc23.x86_64
  [Thread debugging using libthread_db enabled]
  Using host libthread_db library "/lib64/libthread_db.so.1".

 Program received signal SIGSEGV, Segmentation fault.
  0 x00000000004b9ea5 in tracepoint_error (e=0x0, err=13, sys=0x19b1370 "sched", name=0x19a5d00 "sched_switch") at util/parse-events.c:410
  (gdb) bt
  #0  0x00000000004b9ea5 in tracepoint_error (e=0x0, err=13, sys=0x19b1370 "sched", name=0x19a5d00 "sched_switch") at util/parse-events.c:410
  #1  0x00000000004b9fc5 in add_tracepoint (list=0x19a5d20, idx=0x7fffffffb8c0, sys_name=0x19b1370 "sched", evt_name=0x19a5d00 "sched_switch", err=0x0, head_config=0x0)
      at util/parse-events.c:433
  #2  0x00000000004ba334 in add_tracepoint_event (list=0x19a5d20, idx=0x7fffffffb8c0, sys_name=0x19b1370 "sched", evt_name=0x19a5d00 "sched_switch", err=0x0, head_config=0x0)
      at util/parse-events.c:498
  #3  0x00000000004bb699 in parse_events_add_tracepoint (list=0x19a5d20, idx=0x7fffffffb8c0, sys=0x19b1370 "sched", event=0x19a5d00 "sched_switch", err=0x0, head_config=0x0)
      at util/parse-events.c:936
  #4  0x00000000004f6eda in parse_events_parse (_data=0x7fffffffb8b0, scanner=0x19a49d0) at util/parse-events.y:391
  #5  0x00000000004bc8e5 in parse_events__scanner (str=0x663ff2 "sched:sched_switch", data=0x7fffffffb8b0, start_token=258) at util/parse-events.c:1361
  #6  0x00000000004bca57 in parse_events (evlist=0x19a5220, str=0x663ff2 "sched:sched_switch", err=0x0) at util/parse-events.c:1401
  #7  0x0000000000518d5f in perf_evlist__can_select_event (evlist=0x19a3b90, str=0x663ff2 "sched:sched_switch") at util/record.c:253
  #8  0x0000000000553c42 in intel_pt_track_switches (evlist=0x19a3b90) at arch/x86/util/intel-pt.c:364
  #9  0x00000000005549d1 in intel_pt_recording_options (itr=0x19a2c40, evlist=0x19a3b90, opts=0x8edf68 <record+232>) at arch/x86/util/intel-pt.c:664
  #10 0x000000000051e076 in auxtrace_record__options (itr=0x19a2c40, evlist=0x19a3b90, opts=0x8edf68 <record+232>) at util/auxtrace.c:539
  #11 0x0000000000433368 in cmd_record (argc=1, argv=0x7fffffffde60, prefix=0x0) at builtin-record.c:1264
  #12 0x000000000049bec2 in run_builtin (p=0x8fa2a8 <commands+168>, argc=5, argv=0x7fffffffde60) at perf.c:390
  #13 0x000000000049c12a in handle_internal_command (argc=5, argv=0x7fffffffde60) at perf.c:451
  #14 0x000000000049c278 in run_argv (argcp=0x7fffffffdcbc, argv=0x7fffffffdcb0) at perf.c:495
  #15 0x000000000049c60a in main (argc=5, argv=0x7fffffffde60) at perf.c:618
(gdb)

Intel PT attempts to find the sched:sched_switch tracepoint but that seg
faults if tracefs is not readable, because the error reporting structure
is null, as errors are not reported when automatically adding
tracepoints.  Fix by checking before using.

Committer note:

This doesn't take place in a kernel that supports
perf_event_attr.context_switch, that is the default way that will be
used for tracking context switches, only in older kernels, like 4.2, in
a machine with Intel PT (e.g. Broadwell) for non-priviledged users.

Further info from a similar patch by Wang:

The error is in tracepoint_error: it assumes the 'e' parameter is valid.

However, there are many situation a parse_event() can be called without
parse_events_error. See result of

  $ grep 'parse_events(.*NULL)' ./tools/perf/ -r'

Signed-off-by: Adrian Hunter <[email protected]>
Tested-by: Arnaldo Carvalho de Melo <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Josh Poimboeuf <[email protected]>
Cc: Tong Zhang <[email protected]>
Cc: Wang Nan <[email protected]>
Cc: [email protected] # v4.4+
Fixes: 1965817 ("perf tools: Enhance parsing events tracepoint error output")
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
rib pushed a commit that referenced this issue Feb 22, 2016
This patch address a possible security issue:

The request field in client notify request ioctl comes from user space
as u32 and is downcasted to u8 with out validation.
Check request field to have approved values
MEI_HBM_NOTIFICATION_STAR/STOP

Cc: <[email protected]> #4.3+
Signed-off-by: Alexander Usyskin <[email protected]>
Signed-off-by: Tomas Winkler <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Feb 29, 2016
Or Gerlitz says:

====================
Mellanox 10/40G mlx4 driver fixes for 4.5-rc

Bunch of fixes from the team to the mlx4 Eth and core drivers.

Series generated against net commit aac8d3c "qmi_wwan: add "4G LTE usb-modem U901""

Please push patches 1,2 and 6 to -stable  as well

changes from v0:
 - handled another wrongly accounted HW counter in patch rib#1 (Rick)
 - fixed coding style issues in patch rib#4 (Sergei)
====================

Signed-off-by: David S. Miller <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Mar 15, 2016
If we use USB ID pin as wakeup source, and there is a USB block
device on this USB OTG (ID) cable, the system will be deadlock
after system resume.

The root cause for this problem is: the workqueue ci_otg may try
to remove hcd before the driver resume has finished, and hcd will
disconnect the device on it, then, it will call device_release_driver,
and holds the device lock "dev->mutex", but it is never unlocked since
it waits workqueue writeback to run to flush the block information, but
the workqueue writeback is freezable, it is not thawed before driver
resume has finished.

When the driver (device: sd 0:0:0:0:) resume goes to dpm_complete, it
tries to get its device lock "dev->mutex", but it can't get it forever,
then the deadlock occurs. Below call stacks show the situation.

So, in order to fix this problem, we need to change workqueue ci_otg
as freezable, then the work item in this workqueue will be run after
driver's resume, this workqueue will not be blocked forever like above
case since the workqueue writeback has been thawed too.

Tested at: i.mx6qdl-sabresd and i.mx6sx-sdb.

[  555.178869] kworker/u2:13   D c07de74c     0   826      2 0x00000000
[  555.185310] Workqueue: ci_otg ci_otg_work
[  555.189353] Backtrace:
[  555.191849] [<c07de4fc>] (__schedule) from [<c07dec6c>] (schedule+0x48/0xa0)
[  555.198912]  r10:ee471ba0 r9:00000000 r8:00000000 r7:00000002 r6:ee470000 r5:ee471ba4
[  555.206867]  r4:ee470000
[  555.209453] [<c07dec24>] (schedule) from [<c07e2fc4>] (schedule_timeout+0x15c/0x1e0)
[  555.217212]  r4:7fffffff r3:edc2b000
[  555.220862] [<c07e2e68>] (schedule_timeout) from [<c07df6c8>] (wait_for_common+0x94/0x144)
[  555.229140]  r8:00000000 r7:00000002 r6:ee470000 r5:ee471ba4 r4:7fffffff
[  555.235980] [<c07df634>] (wait_for_common) from [<c07df790>] (wait_for_completion+0x18/0x1c)
[  555.244430]  r10:00000001 r9:c0b5563c r8:c0042e48 r7:ef086000 r6:eea4372c r5:ef131b00
[  555.252383]  r4:00000000
[  555.254970] [<c07df778>] (wait_for_completion) from [<c0043cb8>] (flush_work+0x19c/0x234)
[  555.263177] [<c0043b1c>] (flush_work) from [<c0043fac>] (flush_delayed_work+0x48/0x4c)
[  555.271106]  r8:ed5b5000 r7:c0b38a3c r6:eea439cc r5:eea4372c r4:eea4372c
[  555.277958] [<c0043f64>] (flush_delayed_work) from [<c00eae18>] (bdi_unregister+0x84/0xec)
[  555.286236]  r4:eea43520 r3:20000153
[  555.289885] [<c00ead94>] (bdi_unregister) from [<c02c2154>] (blk_cleanup_queue+0x180/0x29c)
[  555.298250]  r5:eea43808 r4:eea43400
[  555.301909] [<c02c1fd4>] (blk_cleanup_queue) from [<c0417914>] (__scsi_remove_device+0x48/0xb8)
[  555.310623]  r7:00000000 r6:20000153 r5:ededa950 r4:ededa800
[  555.316403] [<c04178cc>] (__scsi_remove_device) from [<c0415e90>] (scsi_forget_host+0x64/0x68)
[  555.325028]  r5:ededa800 r4:ed5b5000
[  555.328689] [<c0415e2c>] (scsi_forget_host) from [<c0409828>] (scsi_remove_host+0x78/0x104)
[  555.337054]  r5:ed5b5068 r4:ed5b5000
[  555.340709] [<c04097b0>] (scsi_remove_host) from [<c04cdfcc>] (usb_stor_disconnect+0x50/0xb4)
[  555.349247]  r6:ed5b56e4 r5:ed5b5818 r4:ed5b5690 r3:00000008
[  555.355025] [<c04cdf7c>] (usb_stor_disconnect) from [<c04b3bc8>] (usb_unbind_interface+0x78/0x25c)
[  555.363997]  r8:c13919b4 r7:edd3c000 r6:edd3c020 r5:ee551c68 r4:ee551c00 r3:c04cdf7c
[  555.371892] [<c04b3b50>] (usb_unbind_interface) from [<c03dc248>] (__device_release_driver+0x8c/0x118)
[  555.381213]  r10:00000001 r9:edd90c00 r8:c13919b4 r7:ee551c68 r6:c0b546e0 r5:c0b5563c
[  555.389167]  r4:edd3c020
[  555.391752] [<c03dc1bc>] (__device_release_driver) from [<c03dc2fc>] (device_release_driver+0x28/0x34)
[  555.401071]  r5:edd3c020 r4:edd3c054
[  555.404721] [<c03dc2d4>] (device_release_driver) from [<c03db304>] (bus_remove_device+0xe0/0x110)
[  555.413607]  r5:edd3c020 r4:ef17f04c
[  555.417253] [<c03db224>] (bus_remove_device) from [<c03d8128>] (device_del+0x114/0x21c)
[  555.425270]  r6:edd3c028 r5:edd3c020 r4:ee551c00 r3:00000000
[  555.431045] [<c03d8014>] (device_del) from [<c04b1560>] (usb_disable_device+0xa4/0x1e8)
[  555.439061]  r8:edd3c000 r7:eded8000 r6:00000000 r5:00000001 r4:ee551c00
[  555.445906] [<c04b14bc>] (usb_disable_device) from [<c04a8e54>] (usb_disconnect+0x74/0x224)
[  555.454271]  r9:edd90c00 r8:ee551000 r7:ee551c68 r6:ee551c9c r5:ee551c00 r4:00000001
[  555.462156] [<c04a8de0>] (usb_disconnect) from [<c04a8fb8>] (usb_disconnect+0x1d8/0x224)
[  555.470259]  r10:00000001 r9:edd90000 r8:ee471e2c r7:ee551468 r6:ee55149c r5:ee551400
[  555.478213]  r4:00000001
[  555.480797] [<c04a8de0>] (usb_disconnect) from [<c04ae5ec>] (usb_remove_hcd+0xa0/0x1ac)
[  555.488813]  r10:00000001 r9:ee471eb0 r8:00000000 r7:ef3d9500 r6:eded810c r5:eded80b0
[  555.496765]  r4:eded8000
[  555.499351] [<c04ae54c>] (usb_remove_hcd) from [<c04d4158>] (host_stop+0x28/0x64)
[  555.506847]  r6:eeb50010 r5:eded8000 r4:eeb51010
[  555.511563] [<c04d4130>] (host_stop) from [<c04d09b8>] (ci_otg_work+0xc4/0x124)
[  555.518885]  r6:00000001 r5:eeb50010 r4:eeb502a0 r3:c04d4130
[  555.524665] [<c04d08f4>] (ci_otg_work) from [<c00454f0>] (process_one_work+0x194/0x420)
[  555.532682]  r6:ef086000 r5:eeb502a0 r4:edc44480
[  555.537393] [<c004535c>] (process_one_work) from [<c00457b0>] (worker_thread+0x34/0x514)
[  555.545496]  r10:edc44480 r9:ef086000 r8:c0b1a100 r7:ef086034 r6:00000088 r5:edc44498
[  555.553450]  r4:ef086000
[  555.556032] [<c004577c>] (worker_thread) from [<c004bab4>] (kthread+0xdc/0xf8)
[  555.563268]  r10:00000000 r9:00000000 r8:00000000 r7:c004577c r6:edc44480 r5:eddc15c0
[  555.571221]  r4:00000000
[  555.573804] [<c004b9d8>] (kthread) from [<c000fef0>] (ret_from_fork+0x14/0x24)
[  555.581040]  r7:00000000 r6:00000000 r5:c004b9d8 r4:eddc15c0

[  553.429383] sh              D c07de74c     0   694    691 0x00000000
[  553.435801] Backtrace:
[  553.438295] [<c07de4fc>] (__schedule) from [<c07dec6c>] (schedule+0x48/0xa0)
[  553.445358]  r10:edd3c054 r9:edd3c078 r8:edddbd50 r7:edcbbc00 r6:c1377c34 r5:60000153
[  553.453313]  r4:eddda000
[  553.455896] [<c07dec24>] (schedule) from [<c07deff8>] (schedule_preempt_disabled+0x10/0x14)
[  553.464261]  r4:edd3c058 r3:0000000a
[  553.467910] [<c07defe8>] (schedule_preempt_disabled) from [<c07e0bbc>] (mutex_lock_nested+0x1a0/0x3e8)
[  553.477254] [<c07e0a1c>] (mutex_lock_nested) from [<c03e927c>] (dpm_complete+0xc0/0x1b0)
[  553.485358]  r10:00561408 r9:edd3c054 r8:c0b4863c r7:edddbd90 r6:c0b485d8 r5:edd3c020
[  553.493313]  r4:edd3c0d0
[  553.495896] [<c03e91bc>] (dpm_complete) from [<c03e9388>] (dpm_resume_end+0x1c/0x20)
[  553.503652]  r9:00000000 r8:c0b1a9d0 r7:c1334ec0 r6:c1334edc r5:00000003 r4:00000010
[  553.511544] [<c03e936c>] (dpm_resume_end) from [<c0079894>] (suspend_devices_and_enter+0x158/0x504)
[  553.520604]  r4:00000000 r3:c1334efc
[  553.524250] [<c007973c>] (suspend_devices_and_enter) from [<c0079e74>] (pm_suspend+0x234/0x2cc)
[  553.532961]  r10:00561408 r9:ed6b7300 r8:00000004 r7:c1334eec r6:00000000 r5:c1334ee8
[  553.540914]  r4:00000003
[  553.543493] [<c0079c40>] (pm_suspend) from [<c0078a6c>] (state_store+0x6c/0xc0)

[  555.703684] 7 locks held by kworker/u2:13/826:
[  555.708140]  #0:  ("%s""ci_otg"){++++.+}, at: [<c0045484>] process_one_work+0x128/0x420
[  555.716277]  rib#1:  ((&ci->work)){+.+.+.}, at: [<c0045484>] process_one_work+0x128/0x420
[  555.724317]  rib#2:  (usb_bus_list_lock){+.+.+.}, at: [<c04ae5e4>] usb_remove_hcd+0x98/0x1ac
[  555.732626]  rib#3:  (&dev->mutex){......}, at: [<c04a8e28>] usb_disconnect+0x48/0x224
[  555.740403]  rib#4:  (&dev->mutex){......}, at: [<c04a8e28>] usb_disconnect+0x48/0x224
[  555.748179]  rib#5:  (&dev->mutex){......}, at: [<c03dc2f4>] device_release_driver+0x20/0x34
[  555.756487]  rib#6:  (&shost->scan_mutex){+.+.+.}, at: [<c04097d0>] scsi_remove_host+0x20/0x104

Cc: <[email protected]> #v3.14+
Cc: Jun Li <[email protected]>
Signed-off-by: Peter Chen <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Mar 15, 2016
When computing the residue we need two pieces of information: the current
descriptor and the remaining data of the current descriptor. To get
that information, we need to read consecutively two registers but we
can't do it in an atomic way. For that reason, we have to check manually
that current descriptor has not changed.

Signed-off-by: Ludovic Desroches <[email protected]>
Suggested-by: Cyrille Pitchen <[email protected]>
Reported-by: David Engraf <[email protected]>
Tested-by: David Engraf <[email protected]>
Fixes: e1f7c9e ("dmaengine: at_xdmac: creation of the atmel
eXtended DMA Controller driver")
Cc: [email protected] rib#4.1 and later
Signed-off-by: Vinod Koul <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue May 9, 2016
Both socfpga_dwmac_parse_data() in dwmac-socfpga.c and stmmac_dvr_probe()
in stmmac_main.c functions call devm_reset_control_get() to register an
reset controller for the stmmac. This results in an attempt to register
two reset controllers for the same non-shared reset line.

The first attempt to register the reset controller works fine. The second
attempt fails with warning from the reset controller core, see below.
The warning is produced because the reset line is non-shared and thus
it is allowed to have only up-to one reset controller associated with
that reset line, not two or more.

The solution has multiple parts. First, the original socfpga_dwmac_init()
is tweaked to use reset controller pointer from the stmmac_priv (private
data of the stmmac core) instead of the local instance, which was used
before. The local re-registration of the reset controller is removed.

Next, the socfpga_dwmac_init() is moved after stmmac_dvr_probe() in the
probe function. This order is legal according to Altera and it makes the
code much easier, since there is no need to temporarily register and
unregister the reset controller ; the reset controller is already registered
by the stmmac_dvr_probe().

Finally, plat_dat->exit and socfpga_dwmac_exit() is no longer necessary,
since the functionality is already performed by the stmmac core.

------------[ cut here ]------------
WARNING: CPU: 0 PID: 1 at drivers/reset/core.c:187 __of_reset_control_get+0x218/0x270
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.6.0-rc4-next-20160419-00015-gabb2477-dirty rib#4
Hardware name: Altera SOCFPGA
[<c010f290>] (unwind_backtrace) from [<c010b82c>] (show_stack+0x10/0x14)
[<c010b82c>] (show_stack) from [<c0373da4>] (dump_stack+0x94/0xa8)
[<c0373da4>] (dump_stack) from [<c011bcc0>] (__warn+0xec/0x104)
[<c011bcc0>] (__warn) from [<c011bd88>] (warn_slowpath_null+0x20/0x28)
[<c011bd88>] (warn_slowpath_null) from [<c03a6eb4>] (__of_reset_control_get+0x218/0x270)
[<c03a6eb4>] (__of_reset_control_get) from [<c03a701c>] (__devm_reset_control_get+0x54/0x90)
[<c03a701c>] (__devm_reset_control_get) from [<c041fa30>] (stmmac_dvr_probe+0x1b4/0x8e8)
[<c041fa30>] (stmmac_dvr_probe) from [<c04298c8>] (socfpga_dwmac_probe+0x1b8/0x28c)
[<c04298c8>] (socfpga_dwmac_probe) from [<c03d6ffc>] (platform_drv_probe+0x4c/0xb0)
[<c03d6ffc>] (platform_drv_probe) from [<c03d54ec>] (driver_probe_device+0x224/0x2bc)
[<c03d54ec>] (driver_probe_device) from [<c03d5630>] (__driver_attach+0xac/0xb0)
[<c03d5630>] (__driver_attach) from [<c03d382c>] (bus_for_each_dev+0x6c/0xa0)
[<c03d382c>] (bus_for_each_dev) from [<c03d4ad4>] (bus_add_driver+0x1a4/0x21c)
[<c03d4ad4>] (bus_add_driver) from [<c03d60ac>] (driver_register+0x78/0xf8)
[<c03d60ac>] (driver_register) from [<c0101760>] (do_one_initcall+0x40/0x170)
[<c0101760>] (do_one_initcall) from [<c0800e38>] (kernel_init_freeable+0x1dc/0x27c)
[<c0800e38>] (kernel_init_freeable) from [<c05d1bd4>] (kernel_init+0x8/0x114)
[<c05d1bd4>] (kernel_init) from [<c01076f8>] (ret_from_fork+0x14/0x3c)
---[ end trace 059d2fbe87608fa9 ]---

Signed-off-by: Marek Vasut <[email protected]>
Cc: Matthew Gerlach <[email protected]>
Cc: Dinh Nguyen <[email protected]>
Cc: David S. Miller <[email protected]>
Tested-by: Dinh Nguyen <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Jul 18, 2016
Nicolas Dichtel says:

====================
ovs: fix rtnl notifications on interface deletion

There was no rtnl notifications for interfaces (gre, vxlan, geneve) created
by ovs. This problem is fixed by adjusting the creation path.

v1 -> v2:
 - add patch rib#1 and rib#4
 - rework error handling in patch rib#2
====================

Acked-by: Pravin B Shelar <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Jul 18, 2016
When the core THP code is modifying the permissions of a huge page it
calls pmd_modify(), which unfortunately was clearing the _PAGE_HUGE bit
of the page table entry.  The result can be kernel messages like:

mm/memory.c:397: bad pmd 000000040080004d.
mm/memory.c:397: bad pmd 00000003ff00004d.
mm/memory.c:397: bad pmd 000000040100004d.

or:

------------[ cut here ]------------
WARNING: at mm/mmap.c:3200 exit_mmap+0x150/0x158()
Modules linked in: ipv6 at24 octeon3_ethernet octeon_srio_nexus m25p80
CPU: 12 PID: 1295 Comm: pmderr Not tainted 3.10.87-rt80-Cavium-Octeon rib#4
Stack : 0000000040808000 0000000014009ce1 0000000000400004 ffffffff81076ba0
          0000000000000000 0000000000000000 ffffffff85110000 0000000000000119
          0000000000000004 0000000000000000 0000000000000119 43617669756d2d4f
          0000000000000000 ffffffff850fda40 ffffffff85110000 0000000000000000
          0000000000000000 0000000000000009 ffffffff809207a0 0000000000000c80
          ffffffff80f1bf20 0000000000000001 000000ffeca36828 0000000000000001
          0000000000000000 0000000000000001 000000ffeca7e700 ffffffff80886924
          80000003fd7a0000 80000003fd7a39b0 80000003fdea8000 ffffffff80885780
          80000003fdea8000 ffffffff80f12218 000000000000000c 000000000000050f
          0000000000000000 ffffffff80865c4c 0000000000000000 0000000000000000
          ...
Call Trace:
[<ffffffff80865c4c>] show_stack+0x6c/0xf8
[<ffffffff80885780>] warn_slowpath_common+0x78/0xa8
[<ffffffff809207a0>] exit_mmap+0x150/0x158
[<ffffffff80882d44>] mmput+0x5c/0x110
[<ffffffff8088b450>] do_exit+0x230/0xa68
[<ffffffff8088be34>] do_group_exit+0x54/0x1d0
[<ffffffff8088bfc0>] __wake_up_parent+0x0/0x18

---[ end trace c7b38293191c57dc ]---
BUG: Bad rss-counter state mm:80000003fa168000 idx:1 val:1536

Fix by not clearing _PAGE_HUGE bit.

Signed-off-by: David Daney <[email protected]>
Tested-by: Aaro Koskinen <[email protected]>
Cc: [email protected]
Cc: [email protected]
Patchwork: https://patchwork.linux-mips.org/patch/13687/
Signed-off-by: Ralf Baechle <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Sep 2, 2016
|  CC      mm/memory.o
| In file included from ../mm/memory.c:53:0:
| ../include/linux/pfn_t.h: In function ‘pfn_t_pte’:
| ../include/linux/pfn_t.h:78:2: error: conversion to non-scalar type requested
|  return pfn_pte(pfn_t_to_pfn(pfn), pgprot);

With STRICT_MM_TYPECHECKS pte_t is a struct and the offending code
forces a cast which ends up shifting a struct and hence the gcc warning.

Note that in recent past some of the arches (aarch64, s390) made
STRICT_MM_TYPECHECKS default, but we don't for ARC as this leads to slightly
worse generated code, given ARC ABI definition of returning structs
(which pte_t would become)

Quoting from ARC ABI...

  "Results of type struct are returned in a caller-supplied temporary
  variable whose address is passed in r0.
  For such functions, the arguments are shifted so that they are
  passed in r1 and up."

So
 - struct to be returned would be allocated on stack requiring extra
   code at call sites
 - callee updates stack memory to facilitate the return (vs. simple
   MOV into return reg r0)

Hence STRICT_MM_TYPECHECKS is not enabled by default for ARC

Cc: <[email protected]>   rib#4.4+
Signed-off-by: Vineet Gupta <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Sep 16, 2016
Sunrise Point PCH with SPS Firmware doesn't expose working
MEI interface, we need to quirk it out.
The SPS Firmware is identifiable only on the first PCI function
of the device.

Cc: <[email protected]> rib#4.6+
Tested-by: Sujith Pandel <[email protected]>
Signed-off-by: Tomas Winkler <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Sep 19, 2016
Problems with the signal integrity of the high speed USB data lines or
noise on reference ground lines can cause the i.MX6 USB controller to
violate USB specs and exhibit unexpected behavior.

It was observed that USBi_UI interrupts were triggered first and when
isr_setup_status_phase was called, ci->status was NULL, which lead to a
NULL pointer dereference kernel panic.

This patch fixes the kernel panic, emits a warning once and returns
-EPIPE to halt the device and let the host get stalled.
It also adds a comment to point people, who are experiencing this issue,
to their USB hardware design.

Cc: <[email protected]> rib#4.1+
Signed-off-by: Clemens Gruber <[email protected]>
Signed-off-by: Peter Chen <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Nov 8, 2016
After commit 1cf6e8f ("tty/serial: at91: fix RTS line management
when hardware handshake is enabled"), the hardware handshake wasn't
functional anymore on Atmel platforms (beside SAMA5D2).

To understand why, one has to understand the flag ATMEL_US_USMODE_HWHS
first:
Before commit 1cf6e8f ("tty/serial: at91: fix RTS line management
when hardware handshake is enabled"), this flag was never set.
Thus, the CTS/RTS where only handled by serial_core (and everything
worked just fine).

This commit introduced the use of the ATMEL_US_USMODE_HWHS flag,
enabling it for all boards when the user space enables flow control.

When the ATMEL_US_USMODE_HWHS is set, the Atmel USART controller
handles a part of the flow control job:
- disable the transmitter when the CTS pin gets high.
- drive the RTS pin high when the DMA buffer transfer is completed or
  PDC RX buffer full or RX FIFO is beyond threshold. (depending on the
  controller version).

NB: This feature is *not* mandatory for the flow control to work.
(Nevertheless, it's very useful if low latencies are needed.)

Now, the specifics of the ATMEL_US_USMODE_HWHS flag:

- For platforms with DMAC and no FIFOs (sam9x25, sam9x35, sama5D3,
sama5D4, sam9g15, sam9g25, sam9g35)* this feature simply doesn't work.
( source: https://lkml.org/lkml/2016/9/7/598 )
Tested it on sam9g35, the RTS pins always stays up, even when RXEN=1
or a new DMA transfer descriptor is set.
=> ATMEL_US_USMODE_HWHS must not be used for those platforms

- For platforms with a PDC (sam926{0,1,3}, sam9g10, sam9g20, sam9g45,
sam9g46)*, there's another kind of problem. Once the flag
ATMEL_US_USMODE_HWHS is set, the RTS pin can't be driven anymore via
RTSEN/RTSDIS in USART Control Register. The RTS pin can only be driven
by enabling/disabling the receiver or setting RCR=RNCR=0 in the PDC
(Receive (Next) Counter Register).
=> Doing this is beyond the scope of this patch and could add other
bugs, so the original (and working) behaviour should be set for those
platforms (meaning ATMEL_US_USMODE_HWHS flag should be unset).

- For platforms with a FIFO (sama5d2)*, the RTS pin is driven according
to the RX FIFO thresholds, and can be also driven by RTSEN/RTSDIS in
USART Control Register. No problem here.
(This was the use case of commit 1cf6e8f ("tty/serial: at91: fix
RTS line management when hardware handshake is enabled"))
NB: If the CTS pin declared as a GPIO in the DTS, (for instance
cts-gpios = <&pioA PIN_PB31 GPIO_ACTIVE_LOW>), the transmitter will be
disabled.
=> ATMEL_US_USMODE_HWHS flag can be set for this platform ONLY IF the
CTS pin is not a GPIO.

So, the only case when ATMEL_US_USMODE_HWHS can be enabled is when
(atmel_use_fifo(port) &&
 !mctrl_gpio_to_gpiod(atmel_port->gpios, UART_GPIO_CTS))

Tested on all Atmel USART controller flavours:
AT91SAM9G35-CM (DMAC flavour), AT91SAM9G20-EK (PDC flavour),
SAMA5D2xplained (FIFO flavour).

* the list may not be exhaustive

Cc: <[email protected]> rib#4.4+ (beware, missing atmel_port variable)
Fixes: 1cf6e8f ("tty/serial: at91: fix RTS line management when hardware handshake is enabled")
Signed-off-by: Richard Genoud <[email protected]>
Acked-by: Alexandre Belloni <[email protected]>
Acked-by: Cyrille Pitchen <[email protected]>
Acked-by: Uwe Kleine-König <[email protected]>
Acked-by: Nicolas Ferre <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Dec 6, 2016
We used to use generic implementation of dma_map_ops.mmap which is
dma_common_mmap() but that only worked for simpler cached mappings when
vaddr = paddr.

If a driver requests uncached DMA buffer kernel maps it to virtual
address so that MMU gets involved and page uncached status takes into
account. In that case usage of dma_common_mmap() lead to mapping of
vaddr to vaddr for user-space which is obviously wrong. For more detals
please refer to verbose explanation here [1].

So here we implement our own version of mmap() which always deals
with dma_addr and maps underlying memory to user-space properly
(note that DMA buffer mapped to user-space is always uncached
because there's no way to properly manage cache from user-space).

[1] https://lkml.org/lkml/2016/10/26/973

Reviewed-by: Catalin Marinas <[email protected]>
Cc: Marek Szyprowski <[email protected]>
Cc: <[email protected]>  rib#4.5+
Signed-off-by: Alexey Brodkin <[email protected]>
Signed-off-by: Vineet Gupta <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Dec 6, 2016
The current code doesn't even compile as somehow the inline assembly
can't see the register names defined as ARC_RTC_*
I'm pretty sure It worked when I first got it merged, but the tools were
definitely different then.

So better to write this in "C" anyways.

CC: [email protected]	rib#4.2+
Acked-by: Daniel Lezcano <[email protected]>
Signed-off-by: Vineet Gupta <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Dec 6, 2016
Both ACPI and MP specifications require that the APIC id in the respective
tables must be the same as the APIC id in CPUID.

The kernel retrieves the physical package id from the APIC id during the
ACPI/MP table scan and builds the physical to logical package map. The
physical package id which is used after a CPU comes up is retrieved from
CPUID. So we rely on ACPI/MP tables and CPUID agreeing in that respect.

There exist VMware and XEN implementations which violate the spec. As a
result the physical to logical package map, which relies on the ACPI/MP
tables does not work on those systems, because the CPUID initialized
physical package id does not match the firmware id. This causes system
crashes and malfunction due to invalid package mappings.

The only way to cure this is to sanitize the physical package id after the
CPUID enumeration and yell when the APIC ids are different. Fix up the
initial APIC id, which is fine as it is only used printout purposes.

If the physical package IDs differ yell and use the package information
from the ACPI/MP tables so the existing logical package map just works.

Chas provided the resulting dmesg output for his affected 4 virtual
sockets, 1 core per socket VM:

[Firmware Bug]: CPU1: APIC id mismatch. Firmware: 1 CPUID: 2
[Firmware Bug]: CPU1: Using firmware package id 1 instead of 2
....

Reported-and-tested-by: "Charles (Chas) Williams" <[email protected]>,
Reported-by: M. Vefa Bicakci <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Sebastian Andrzej Siewior <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Alok Kataria <[email protected]>
Cc: Boris Ostrovsky <[email protected]>
Cc: rib#4.6+ <stable@vger,kernel.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1611091613540.3501@nanos
Signed-off-by: Thomas Gleixner <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Dec 6, 2016
When booting up LDOM, find_node() warns that a physical address
doesn't match a NUMA node.

WARNING: CPU: 0 PID: 0 at arch/sparc/mm/init_64.c:835
find_node+0xf4/0x120 find_node: A physical address doesn't
match a NUMA node rule. Some physical memory will be
owned by node 0.Modules linked in:

CPU: 0 PID: 0 Comm: swapper Not tainted 4.9.0-rc3 rib#4
Call Trace:
 [0000000000468ba0] __warn+0xc0/0xe0
 [0000000000468c74] warn_slowpath_fmt+0x34/0x60
 [00000000004592f4] find_node+0xf4/0x120
 [0000000000dd0774] add_node_ranges+0x38/0xe4
 [0000000000dd0b1c] numa_parse_mdesc+0x268/0x2e4
 [0000000000dd0e9c] bootmem_init+0xb8/0x160
 [0000000000dd174c] paging_init+0x808/0x8fc
 [0000000000dcb0d0] setup_arch+0x2c8/0x2f0
 [0000000000dc68a0] start_kernel+0x48/0x424
 [0000000000dcb374] start_early_boot+0x27c/0x28c
 [0000000000a32c08] tlb_fixup_done+0x4c/0x64
 [0000000000027f08] 0x27f08

It is because linux use an internal structure node_masks[] to
keep the best memory latency node only. However, LDOM mdesc can
contain single latency-group with multiple memory latency nodes.

If the address doesn't match the best latency node within
node_masks[], it should check for an alternative via mdesc.
The warning message should only be printed if the address
doesn't match any node_masks[] nor within mdesc. To minimize
the impact of searching mdesc every time, the last matched
mask and index is stored in a variable.

Signed-off-by: Thomas Tai <[email protected]>
Reviewed-by: Chris Hyser <[email protected]>
Reviewed-by: Liam Merwick <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Dec 6, 2016
commit 1c3c909 broke PAE40. Macro pfn_pte(pfn, prot) creates paddr
from pfn, but the page shift was getting truncated to 32 bits since we lost
the proper cast to 64 bits (for PAE400

Instead of reverting that commit, use a better helper which is 32/64 bits
safe just like ARM implementation.

Fixes: 1c3c909 ("ARC: mm: fix build breakage with STRICT_MM_TYPECHECKS")
Cc: <[email protected]>   rib#4.4+
Signed-off-by: Yuriy Kolerov <[email protected]>
[vgupta: massaged changelog]
Signed-off-by: Vineet Gupta <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Jan 26, 2017
commit d65283f added mod->arch.secstr under
CONFIG_ARC_DW2_UNWIND, but used it unconditionally which broke builds
when the option was disabled. Fix that by adjusting the #ifdef guard.

And while at it add a missing guard (for unwinder) in module.c as well

Reported-by: Waldemar Brodkorb <[email protected]>
Cc: [email protected]    rib#4.9
Fixes: d65283f ("ARC: module: elide loop to save reference to .eh_frame")
Tested-by: Anton Kolesov <[email protected]>
Reviewed-by: Alexey Brodkin <[email protected]>
[abrodkin: provided fixlet to Kconfig per failure in allnoconfig build]
Signed-off-by: Vineet Gupta <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Feb 16, 2017
…_EXT

If there is no OPREGION_ASLE_EXT then a VBT stored in mailbox rib#4 may
use the ASLE_EXT parts of the opregion. Adjust the vbt_size calculation
for a vbt in mailbox rib#4 for this.

This fixes the driver not finding the VBT on a jumper ezpad mini3
cherrytrail tablet and on a ACER SW5_017 machine.

Cc: [email protected]
Signed-off-by: Hans de Goede <[email protected]>
Signed-off-by: Jani Nikula <[email protected]>
Link: http://patchwork.freedesktop.org/patch/msgid/[email protected]
matt-auld pushed a commit to matt-auld/linux that referenced this issue Feb 16, 2017
…_EXT

If there is no OPREGION_ASLE_EXT then a VBT stored in mailbox rib#4 may
use the ASLE_EXT parts of the opregion. Adjust the vbt_size calculation
for a vbt in mailbox rib#4 for this.

This fixes the driver not finding the VBT on a jumper ezpad mini3
cherrytrail tablet and on a ACER SW5_017 machine.

Cc: [email protected]
Signed-off-by: Hans de Goede <[email protected]>
Signed-off-by: Jani Nikula <[email protected]>
Link: http://patchwork.freedesktop.org/patch/msgid/[email protected]
(cherry picked from commit dfb65e7)
Signed-off-by: Jani Nikula <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Feb 16, 2017
…_EXT

If there is no OPREGION_ASLE_EXT then a VBT stored in mailbox rib#4 may
use the ASLE_EXT parts of the opregion. Adjust the vbt_size calculation
for a vbt in mailbox rib#4 for this.

This fixes the driver not finding the VBT on a jumper ezpad mini3
cherrytrail tablet and on a ACER SW5_017 machine.

Cc: [email protected]
Signed-off-by: Hans de Goede <[email protected]>
Signed-off-by: Jani Nikula <[email protected]>
Link: http://patchwork.freedesktop.org/patch/msgid/[email protected]
(cherry picked from commit dfb65e7)
Signed-off-by: Jani Nikula <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Feb 21, 2017
We cannot do printk() from tk_debug_account_sleep_time(), because
tk_debug_account_sleep_time() is called under tk_core seq lock.
The reason why printk() is unsafe there is that console_sem may
invoke scheduler (up()->wake_up_process()->activate_task()), which,
in turn, can return back to timekeeping code, for instance, via
get_time()->ktime_get(), deadlocking the system on tk_core seq lock.

[   48.950592] ======================================================
[   48.950622] [ INFO: possible circular locking dependency detected ]
[   48.950622] 4.10.0-rc7-next-20170213+ torvalds#101 Not tainted
[   48.950622] -------------------------------------------------------
[   48.950622] kworker/0:0/3 is trying to acquire lock:
[   48.950653]  (tk_core){----..}, at: [<c01cc624>] retrigger_next_event+0x4c/0x90
[   48.950683]
               but task is already holding lock:
[   48.950683]  (hrtimer_bases.lock){-.-...}, at: [<c01cc610>] retrigger_next_event+0x38/0x90
[   48.950714]
               which lock already depends on the new lock.

[   48.950714]
               the existing dependency chain (in reverse order) is:
[   48.950714]
               -> rib#5 (hrtimer_bases.lock){-.-...}:
[   48.950744]        _raw_spin_lock_irqsave+0x50/0x64
[   48.950775]        lock_hrtimer_base+0x28/0x58
[   48.950775]        hrtimer_start_range_ns+0x20/0x5c8
[   48.950775]        __enqueue_rt_entity+0x320/0x360
[   48.950805]        enqueue_rt_entity+0x2c/0x44
[   48.950805]        enqueue_task_rt+0x24/0x94
[   48.950836]        ttwu_do_activate+0x54/0xc0
[   48.950836]        try_to_wake_up+0x248/0x5c8
[   48.950836]        __setup_irq+0x420/0x5f0
[   48.950836]        request_threaded_irq+0xdc/0x184
[   48.950866]        devm_request_threaded_irq+0x58/0xa4
[   48.950866]        omap_i2c_probe+0x530/0x6a0
[   48.950897]        platform_drv_probe+0x50/0xb0
[   48.950897]        driver_probe_device+0x1f8/0x2cc
[   48.950897]        __driver_attach+0xc0/0xc4
[   48.950927]        bus_for_each_dev+0x6c/0xa0
[   48.950927]        bus_add_driver+0x100/0x210
[   48.950927]        driver_register+0x78/0xf4
[   48.950958]        do_one_initcall+0x3c/0x16c
[   48.950958]        kernel_init_freeable+0x20c/0x2d8
[   48.950958]        kernel_init+0x8/0x110
[   48.950988]        ret_from_fork+0x14/0x24
[   48.950988]
               -> rib#4 (&rt_b->rt_runtime_lock){-.-...}:
[   48.951019]        _raw_spin_lock+0x40/0x50
[   48.951019]        rq_offline_rt+0x9c/0x2bc
[   48.951019]        set_rq_offline.part.2+0x2c/0x58
[   48.951049]        rq_attach_root+0x134/0x144
[   48.951049]        cpu_attach_domain+0x18c/0x6f4
[   48.951049]        build_sched_domains+0xba4/0xd80
[   48.951080]        sched_init_smp+0x68/0x10c
[   48.951080]        kernel_init_freeable+0x160/0x2d8
[   48.951080]        kernel_init+0x8/0x110
[   48.951080]        ret_from_fork+0x14/0x24
[   48.951110]
               -> rib#3 (&rq->lock){-.-.-.}:
[   48.951110]        _raw_spin_lock+0x40/0x50
[   48.951141]        task_fork_fair+0x30/0x124
[   48.951141]        sched_fork+0x194/0x2e0
[   48.951141]        copy_process.part.5+0x448/0x1a20
[   48.951171]        _do_fork+0x98/0x7e8
[   48.951171]        kernel_thread+0x2c/0x34
[   48.951171]        rest_init+0x1c/0x18c
[   48.951202]        start_kernel+0x35c/0x3d4
[   48.951202]        0x8000807c
[   48.951202]
               -> rib#2 (&p->pi_lock){-.-.-.}:
[   48.951232]        _raw_spin_lock_irqsave+0x50/0x64
[   48.951232]        try_to_wake_up+0x30/0x5c8
[   48.951232]        up+0x4c/0x60
[   48.951263]        __up_console_sem+0x2c/0x58
[   48.951263]        console_unlock+0x3b4/0x650
[   48.951263]        vprintk_emit+0x270/0x474
[   48.951293]        vprintk_default+0x20/0x28
[   48.951293]        printk+0x20/0x30
[   48.951324]        kauditd_hold_skb+0x94/0xb8
[   48.951324]        kauditd_thread+0x1a4/0x56c
[   48.951324]        kthread+0x104/0x148
[   48.951354]        ret_from_fork+0x14/0x24
[   48.951354]
               -> rib#1 ((console_sem).lock){-.....}:
[   48.951385]        _raw_spin_lock_irqsave+0x50/0x64
[   48.951385]        down_trylock+0xc/0x2c
[   48.951385]        __down_trylock_console_sem+0x24/0x80
[   48.951385]        console_trylock+0x10/0x8c
[   48.951416]        vprintk_emit+0x264/0x474
[   48.951416]        vprintk_default+0x20/0x28
[   48.951416]        printk+0x20/0x30
[   48.951446]        tk_debug_account_sleep_time+0x5c/0x70
[   48.951446]        __timekeeping_inject_sleeptime.constprop.3+0x170/0x1a0
[   48.951446]        timekeeping_resume+0x218/0x23c
[   48.951477]        syscore_resume+0x94/0x42c
[   48.951477]        suspend_enter+0x554/0x9b4
[   48.951477]        suspend_devices_and_enter+0xd8/0x4b4
[   48.951507]        enter_state+0x934/0xbd4
[   48.951507]        pm_suspend+0x14/0x70
[   48.951507]        state_store+0x68/0xc8
[   48.951538]        kernfs_fop_write+0xf4/0x1f8
[   48.951538]        __vfs_write+0x1c/0x114
[   48.951538]        vfs_write+0xa0/0x168
[   48.951568]        SyS_write+0x3c/0x90
[   48.951568]        __sys_trace_return+0x0/0x10
[   48.951568]
               -> #0 (tk_core){----..}:
[   48.951599]        lock_acquire+0xe0/0x294
[   48.951599]        ktime_get_update_offsets_now+0x5c/0x1d4
[   48.951629]        retrigger_next_event+0x4c/0x90
[   48.951629]        on_each_cpu+0x40/0x7c
[   48.951629]        clock_was_set_work+0x14/0x20
[   48.951660]        process_one_work+0x2b4/0x808
[   48.951660]        worker_thread+0x3c/0x550
[   48.951660]        kthread+0x104/0x148
[   48.951690]        ret_from_fork+0x14/0x24
[   48.951690]
               other info that might help us debug this:

[   48.951690] Chain exists of:
                 tk_core --> &rt_b->rt_runtime_lock --> hrtimer_bases.lock

[   48.951721]  Possible unsafe locking scenario:

[   48.951721]        CPU0                    CPU1
[   48.951721]        ----                    ----
[   48.951721]   lock(hrtimer_bases.lock);
[   48.951751]                                lock(&rt_b->rt_runtime_lock);
[   48.951751]                                lock(hrtimer_bases.lock);
[   48.951751]   lock(tk_core);
[   48.951782]
                *** DEADLOCK ***

[   48.951782] 3 locks held by kworker/0:0/3:
[   48.951782]  #0:  ("events"){.+.+.+}, at: [<c0156590>] process_one_work+0x1f8/0x808
[   48.951812]  rib#1:  (hrtimer_work){+.+...}, at: [<c0156590>] process_one_work+0x1f8/0x808
[   48.951843]  rib#2:  (hrtimer_bases.lock){-.-...}, at: [<c01cc610>] retrigger_next_event+0x38/0x90
[   48.951843]   stack backtrace:
[   48.951873] CPU: 0 PID: 3 Comm: kworker/0:0 Not tainted 4.10.0-rc7-next-20170213+
[   48.951904] Workqueue: events clock_was_set_work
[   48.951904] [<c0110208>] (unwind_backtrace) from [<c010c224>] (show_stack+0x10/0x14)
[   48.951934] [<c010c224>] (show_stack) from [<c04ca6c0>] (dump_stack+0xac/0xe0)
[   48.951934] [<c04ca6c0>] (dump_stack) from [<c019b5cc>] (print_circular_bug+0x1d0/0x308)
[   48.951965] [<c019b5cc>] (print_circular_bug) from [<c019d2a8>] (validate_chain+0xf50/0x1324)
[   48.951965] [<c019d2a8>] (validate_chain) from [<c019ec18>] (__lock_acquire+0x468/0x7e8)
[   48.951995] [<c019ec18>] (__lock_acquire) from [<c019f634>] (lock_acquire+0xe0/0x294)
[   48.951995] [<c019f634>] (lock_acquire) from [<c01d0ea0>] (ktime_get_update_offsets_now+0x5c/0x1d4)
[   48.952026] [<c01d0ea0>] (ktime_get_update_offsets_now) from [<c01cc624>] (retrigger_next_event+0x4c/0x90)
[   48.952026] [<c01cc624>] (retrigger_next_event) from [<c01e4e24>] (on_each_cpu+0x40/0x7c)
[   48.952056] [<c01e4e24>] (on_each_cpu) from [<c01cafc4>] (clock_was_set_work+0x14/0x20)
[   48.952056] [<c01cafc4>] (clock_was_set_work) from [<c015664c>] (process_one_work+0x2b4/0x808)
[   48.952087] [<c015664c>] (process_one_work) from [<c0157774>] (worker_thread+0x3c/0x550)
[   48.952087] [<c0157774>] (worker_thread) from [<c015d644>] (kthread+0x104/0x148)
[   48.952087] [<c015d644>] (kthread) from [<c0107830>] (ret_from_fork+0x14/0x24)

Replace printk() with printk_deferred(), which does not call into
the scheduler.

Fixes: 0bf43f1 ("timekeeping: Prints the amounts of time spent during suspend")
Reported-and-tested-by: Tony Lindgren <[email protected]>
Signed-off-by: Sergey Senozhatsky <[email protected]>
Cc: Petr Mladek <[email protected]>
Cc: Sergey Senozhatsky <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: "Rafael J . Wysocki" <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: John Stultz <[email protected]>
Cc: "[4.9+]" <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Thomas Gleixner <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Mar 8, 2017
This patch adds crypto_requires_off which is an extension of
crypto_requires_sync for similar bits such as NEED_FALLBACK.

Cc: [email protected] rib#4.10
Suggested-by: Marcelo Cerri <[email protected]>
Signed-off-by: Herbert Xu <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Mar 8, 2017
When we're used as a fallback algorithm, we should propagate
the NEED_FALLBACK bit when searching for the underlying ECB mode.

This just happens to fix a hang too because otherwise the search
may end up loading the same module that triggered this XTS creation.

Cc: [email protected] rib#4.10
Fixes: f1c131b ("crypto: xts - Convert to skcipher")
Reported-by: Harald Freudenberger <[email protected]>
Signed-off-by: Herbert Xu <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Mar 8, 2017
Cc: [email protected] rib#4.10
Signed-off-by: Paulo Flabiano Smorigo <[email protected]>
Signed-off-by: Herbert Xu <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Mar 8, 2017
Cc: [email protected] rib#4.10
Signed-off-by: Paulo Flabiano Smorigo <[email protected]>
Signed-off-by: Herbert Xu <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Mar 8, 2017
The code where sk_clone() came from created a new socket and locked it,
but then, on the error path didn't unlock it.

This problem stayed there for a long while, till b0691c8 ("net:
Unlock sock before calling sk_free()") fixed it, but unfortunately the
callers of sk_clone() (now sk_clone_locked()) were not audited and the
one in dccp_create_openreq_child() remained.

Now in the age of the syskaller fuzzer, this was finally uncovered, as
reported by Dmitry:

 ---- 8< ----

I've got the following report while running syzkaller fuzzer on
86292b3 ("Merge branch 'akpm' (patches from Andrew)")

  [ BUG: held lock freed! ]
  4.10.0+ torvalds#234 Not tainted
  -------------------------
  syz-executor6/6898 is freeing memory
  ffff88006286cac0-ffff88006286d3b7, with a lock still held there!
   (slock-AF_INET6){+.-...}, at: [<ffffffff8362c2c9>] spin_lock
  include/linux/spinlock.h:299 [inline]
   (slock-AF_INET6){+.-...}, at: [<ffffffff8362c2c9>]
  sk_clone_lock+0x3d9/0x12c0 net/core/sock.c:1504
  5 locks held by syz-executor6/6898:
   #0:  (sk_lock-AF_INET6){+.+.+.}, at: [<ffffffff839a34b4>] lock_sock
  include/net/sock.h:1460 [inline]
   #0:  (sk_lock-AF_INET6){+.+.+.}, at: [<ffffffff839a34b4>]
  inet_stream_connect+0x44/0xa0 net/ipv4/af_inet.c:681
   rib#1:  (rcu_read_lock){......}, at: [<ffffffff83bc1c2a>]
  inet6_csk_xmit+0x12a/0x5d0 net/ipv6/inet6_connection_sock.c:126
   rib#2:  (rcu_read_lock){......}, at: [<ffffffff8369b424>] __skb_unlink
  include/linux/skbuff.h:1767 [inline]
   rib#2:  (rcu_read_lock){......}, at: [<ffffffff8369b424>] __skb_dequeue
  include/linux/skbuff.h:1783 [inline]
   rib#2:  (rcu_read_lock){......}, at: [<ffffffff8369b424>]
  process_backlog+0x264/0x730 net/core/dev.c:4835
   rib#3:  (rcu_read_lock){......}, at: [<ffffffff83aeb5c0>]
  ip6_input_finish+0x0/0x1700 net/ipv6/ip6_input.c:59
   rib#4:  (slock-AF_INET6){+.-...}, at: [<ffffffff8362c2c9>] spin_lock
  include/linux/spinlock.h:299 [inline]
   rib#4:  (slock-AF_INET6){+.-...}, at: [<ffffffff8362c2c9>]
  sk_clone_lock+0x3d9/0x12c0 net/core/sock.c:1504

Fix it just like was done by b0691c8 ("net: Unlock sock before calling
sk_free()").

Reported-by: Dmitry Vyukov <[email protected]>
Cc: Cong Wang <[email protected]>
Cc: Eric Dumazet <[email protected]>
Cc: Gerrit Renker <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
rib pushed a commit that referenced this issue Mar 23, 2017
Yuval Mintz says:

====================
qed: Fixes series

This address several different issues in qed.
The more significant portions:

Patch #1 would cause timeout when qedr utilizes the highest
CIDs availble for it [or when future qede adapters would utilize
queues in some constellations].

Patch #4 fixes a leak of mapped addresses; When iommu is enabled,
offloaded storage protocols might eventually run out of resources
and fail to map additional buffers.

Patches #6,#7 were missing in the initial iSCSI infrastructure
submissions, and would hamper qedi's stability when it reaches
out-of-order scenarios.
====================

Signed-off-by: David S. Miller <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Mar 31, 2017
The CPPI 4.1 driver polls register to workaround the premature TX
interrupt issue, but it causes audio playback underrun when triggered in
Isoch transfers.

Isoch doesn't do back-to-back transfers, the TX should be done by the
time the next transfer is scheduled. So skip this polling workaround for
Isoch transfer.

Fixes: a655f48 ("usb: musb: musb_cppi41: handle pre-mature TX complete interrupt")
Cc: <[email protected]> rib#4.1+
Reported-by: Alexandre Bailon <[email protected]>
Acked-by: Sebastian Andrzej Siewior <[email protected]>
Tested-by: Alexandre Bailon <[email protected]>
Signed-off-by: Bin Liu <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Mar 31, 2017
The DSPS glue calls del_timer_sync() in its musb_platform_disable()
implementation, which requires the caller to not hold a lock. But
musb_remove() calls musb_platform_disable() will musb->lock held. This
could causes spinlock deadlock.

So change musb_remove() to call musb_platform_disable() without holds
musb->lock. This doesn't impact the musb_platform_disable implementation
in other glue drivers.

root@am335x-evm:~# modprobe -r musb-dsps
[  126.134879] musb-hdrc musb-hdrc.1: remove, state 1
[  126.140465] usb usb2: USB disconnect, device number 1
[  126.146178] usb 2-1: USB disconnect, device number 2
[  126.416985] musb-hdrc musb-hdrc.1: USB bus 2 deregistered
[  126.423943]
[  126.425525] ======================================================
[  126.431997] [ INFO: possible circular locking dependency detected ]
[  126.438564] 4.11.0-rc1-00003-g1557f13bca04-dirty torvalds#77 Not tainted
[  126.444852] -------------------------------------------------------
[  126.451414] modprobe/778 is trying to acquire lock:
[  126.456523]  (((&glue->timer))){+.-...}, at: [<c01b8788>] del_timer_sync+0x0/0xd0
[  126.464403]
[  126.464403] but task is already holding lock:
[  126.470511]  (&(&musb->lock)->rlock){-.-...}, at: [<bf30b7f8>] musb_remove+0x50/0x1
30 [musb_hdrc]
[  126.479965]
[  126.479965] which lock already depends on the new lock.
[  126.479965]
[  126.488531]
[  126.488531] the existing dependency chain (in reverse order) is:
[  126.496368]
[  126.496368] -> rib#1 (&(&musb->lock)->rlock){-.-...}:
[  126.502968]        otg_timer+0x80/0xec [musb_dsps]
[  126.507990]        call_timer_fn+0xb4/0x390
[  126.512372]        expire_timers+0xf0/0x1fc
[  126.516754]        run_timer_softirq+0x80/0x178
[  126.521511]        __do_softirq+0xc4/0x554
[  126.525802]        irq_exit+0xe8/0x158
[  126.529735]        __handle_domain_irq+0x58/0xb8
[  126.534583]        __irq_usr+0x54/0x80
[  126.538507]
[  126.538507] -> #0 (((&glue->timer))){+.-...}:
[  126.544636]        del_timer_sync+0x40/0xd0
[  126.549066]        musb_remove+0x6c/0x130 [musb_hdrc]
[  126.554370]        platform_drv_remove+0x24/0x3c
[  126.559206]        device_release_driver_internal+0x14c/0x1e0
[  126.565225]        bus_remove_device+0xd8/0x108
[  126.569970]        device_del+0x1e4/0x308
[  126.574170]        platform_device_del+0x24/0x8c
[  126.579006]        platform_device_unregister+0xc/0x20
[  126.584394]        dsps_remove+0x14/0x30 [musb_dsps]
[  126.589595]        platform_drv_remove+0x24/0x3c
[  126.594432]        device_release_driver_internal+0x14c/0x1e0
[  126.600450]        driver_detach+0x38/0x6c
[  126.604740]        bus_remove_driver+0x4c/0xa0
[  126.609407]        SyS_delete_module+0x11c/0x1e4
[  126.614252]        __sys_trace_return+0x0/0x10

Fixes: ea2f35c ("usb: musb: Fix sleeping function called from invalid context for hdrc glue")
Cc: <[email protected]> rib#4.9+
Acked-by: Tony Lindgren <[email protected]>
Signed-off-by: Bin Liu <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Mar 29, 2019
…_event_on_all_cpus test

  =================================================================
  ==7497==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 40 byte(s) in 1 object(s) allocated from:
      #0 0x7f0333a88f30 in __interceptor_malloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xedf30)
      rib#1 0x5625e5326213 in cpu_map__trim_new util/cpumap.c:45
      rib#2 0x5625e5326703 in cpu_map__read util/cpumap.c:103
      rib#3 0x5625e53267ef in cpu_map__read_all_cpu_map util/cpumap.c:120
      rib#4 0x5625e5326915 in cpu_map__new util/cpumap.c:135
      rib#5 0x5625e517b355 in test__openat_syscall_event_on_all_cpus tests/openat-syscall-all-cpus.c:36
      rib#6 0x5625e51528e6 in run_test tests/builtin-test.c:358
      rib#7 0x5625e5152baf in test_and_print tests/builtin-test.c:388
      rib#8 0x5625e51543fe in __cmd_test tests/builtin-test.c:583
      rib#9 0x5625e515572f in cmd_test tests/builtin-test.c:722
      rib#10 0x5625e51c3fb8 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302
      rib#11 0x5625e51c44f7 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354
      rib#12 0x5625e51c48fb in run_argv /home/changbin/work/linux/tools/perf/perf.c:398
      rib#13 0x5625e51c5069 in main /home/changbin/work/linux/tools/perf/perf.c:520
      rib#14 0x7f033214d09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)

Signed-off-by: Changbin Du <[email protected]>
Reviewed-by: Jiri Olsa <[email protected]>
Cc: Alexei Starovoitov <[email protected]>
Cc: Daniel Borkmann <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Steven Rostedt (VMware) <[email protected]>
Fixes: f30a79b ("perf tools: Add reference counting for cpu_map object")
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Mar 29, 2019
  =================================================================
  ==7506==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 13 byte(s) in 3 object(s) allocated from:
      #0 0x7f03339d6070 in __interceptor_strdup (/usr/lib/x86_64-linux-gnu/libasan.so.5+0x3b070)
      rib#1 0x5625e53aaef0 in expr__find_other util/expr.y:221
      rib#2 0x5625e51bcd3f in test__expr tests/expr.c:52
      rib#3 0x5625e51528e6 in run_test tests/builtin-test.c:358
      rib#4 0x5625e5152baf in test_and_print tests/builtin-test.c:388
      rib#5 0x5625e51543fe in __cmd_test tests/builtin-test.c:583
      rib#6 0x5625e515572f in cmd_test tests/builtin-test.c:722
      rib#7 0x5625e51c3fb8 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302
      rib#8 0x5625e51c44f7 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354
      rib#9 0x5625e51c48fb in run_argv /home/changbin/work/linux/tools/perf/perf.c:398
      rib#10 0x5625e51c5069 in main /home/changbin/work/linux/tools/perf/perf.c:520
      rib#11 0x7f033214d09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)

Signed-off-by: Changbin Du <[email protected]>
Cc: Alexei Starovoitov <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Daniel Borkmann <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Steven Rostedt (VMware) <[email protected]>
Fixes: 0751673 ("perf tools: Add a simple expression parser for JSON")
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Mar 29, 2019
  =================================================================
  ==20875==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 1160 byte(s) in 1 object(s) allocated from:
      #0 0x7f1b6fc84138 in calloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xee138)
      rib#1 0x55bd50005599 in zalloc util/util.h:23
      rib#2 0x55bd500068f5 in perf_evsel__newtp_idx util/evsel.c:327
      rib#3 0x55bd4ff810fc in perf_evsel__newtp /home/work/linux/tools/perf/util/evsel.h:216
      rib#4 0x55bd4ff81608 in test__perf_evsel__tp_sched_test tests/evsel-tp-sched.c:69
      rib#5 0x55bd4ff528e6 in run_test tests/builtin-test.c:358
      rib#6 0x55bd4ff52baf in test_and_print tests/builtin-test.c:388
      rib#7 0x55bd4ff543fe in __cmd_test tests/builtin-test.c:583
      rib#8 0x55bd4ff5572f in cmd_test tests/builtin-test.c:722
      rib#9 0x55bd4ffc4087 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302
      rib#10 0x55bd4ffc45c6 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354
      rib#11 0x55bd4ffc49ca in run_argv /home/changbin/work/linux/tools/perf/perf.c:398
      rib#12 0x55bd4ffc5138 in main /home/changbin/work/linux/tools/perf/perf.c:520
      rib#13 0x7f1b6e34809a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)

  Indirect leak of 19 byte(s) in 1 object(s) allocated from:
      #0 0x7f1b6fc83f30 in __interceptor_malloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xedf30)
      rib#1 0x7f1b6e3ac30f in vasprintf (/lib/x86_64-linux-gnu/libc.so.6+0x8830f)

Signed-off-by: Changbin Du <[email protected]>
Reviewed-by: Jiri Olsa <[email protected]>
Cc: Alexei Starovoitov <[email protected]>
Cc: Daniel Borkmann <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Steven Rostedt (VMware) <[email protected]>
Fixes: 6a6cd11 ("perf test: Add test for the sched tracepoint format fields")
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Apr 2, 2019
…mory

When halting a guest, QEMU flushes the virtual ITS caches, which
amounts to writing to the various tables that the guest has allocated.

When doing this, we fail to take the srcu lock, and the kernel
shouts loudly if running a lockdep kernel:

[   69.680416] =============================
[   69.680819] WARNING: suspicious RCU usage
[   69.681526] 5.1.0-rc1-00008-g600025238f51-dirty rib#18 Not tainted
[   69.682096] -----------------------------
[   69.682501] ./include/linux/kvm_host.h:605 suspicious rcu_dereference_check() usage!
[   69.683225]
[   69.683225] other info that might help us debug this:
[   69.683225]
[   69.683975]
[   69.683975] rcu_scheduler_active = 2, debug_locks = 1
[   69.684598] 6 locks held by qemu-system-aar/4097:
[   69.685059]  #0: 0000000034196013 (&kvm->lock){+.+.}, at: vgic_its_set_attr+0x244/0x3a0
[   69.686087]  rib#1: 00000000f2ed935e (&its->its_lock){+.+.}, at: vgic_its_set_attr+0x250/0x3a0
[   69.686919]  rib#2: 000000005e71ea54 (&vcpu->mutex){+.+.}, at: lock_all_vcpus+0x64/0xd0
[   69.687698]  rib#3: 00000000c17e548d (&vcpu->mutex){+.+.}, at: lock_all_vcpus+0x64/0xd0
[   69.688475]  rib#4: 00000000ba386017 (&vcpu->mutex){+.+.}, at: lock_all_vcpus+0x64/0xd0
[   69.689978]  rib#5: 00000000c2c3c335 (&vcpu->mutex){+.+.}, at: lock_all_vcpus+0x64/0xd0
[   69.690729]
[   69.690729] stack backtrace:
[   69.691151] CPU: 2 PID: 4097 Comm: qemu-system-aar Not tainted 5.1.0-rc1-00008-g600025238f51-dirty rib#18
[   69.691984] Hardware name: rockchip evb_rk3399/evb_rk3399, BIOS 2019.04-rc3-00124-g2feec69fb1 03/15/2019
[   69.692831] Call trace:
[   69.694072]  lockdep_rcu_suspicious+0xcc/0x110
[   69.694490]  gfn_to_memslot+0x174/0x190
[   69.694853]  kvm_write_guest+0x50/0xb0
[   69.695209]  vgic_its_save_tables_v0+0x248/0x330
[   69.695639]  vgic_its_set_attr+0x298/0x3a0
[   69.696024]  kvm_device_ioctl_attr+0x9c/0xd8
[   69.696424]  kvm_device_ioctl+0x8c/0xf8
[   69.696788]  do_vfs_ioctl+0xc8/0x960
[   69.697128]  ksys_ioctl+0x8c/0xa0
[   69.697445]  __arm64_sys_ioctl+0x28/0x38
[   69.697817]  el0_svc_common+0xd8/0x138
[   69.698173]  el0_svc_handler+0x38/0x78
[   69.698528]  el0_svc+0x8/0xc

The fix is to obviously take the srcu lock, just like we do on the
read side of things since bf30824. One wonders why this wasn't
fixed at the same time, but hey...

Fixes: bf30824 ("KVM: arm/arm64: VGIC/ITS: protect kvm_read_guest() calls with SRCU lock")
Signed-off-by: Marc Zyngier <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Apr 2, 2019
Calling kvm_is_visible_gfn() implies that we're parsing the memslots,
and doing this without the srcu lock is frown upon:

[12704.164532] =============================
[12704.164544] WARNING: suspicious RCU usage
[12704.164560] 5.1.0-rc1-00008-g600025238f51-dirty rib#16 Tainted: G        W
[12704.164573] -----------------------------
[12704.164589] ./include/linux/kvm_host.h:605 suspicious rcu_dereference_check() usage!
[12704.164602] other info that might help us debug this:
[12704.164616] rcu_scheduler_active = 2, debug_locks = 1
[12704.164631] 6 locks held by qemu-system-aar/13968:
[12704.164644]  #0: 000000007ebdae4f (&kvm->lock){+.+.}, at: vgic_its_set_attr+0x244/0x3a0
[12704.164691]  rib#1: 000000007d751022 (&its->its_lock){+.+.}, at: vgic_its_set_attr+0x250/0x3a0
[12704.164726]  rib#2: 00000000219d2706 (&vcpu->mutex){+.+.}, at: lock_all_vcpus+0x64/0xd0
[12704.164761]  rib#3: 00000000a760aecd (&vcpu->mutex){+.+.}, at: lock_all_vcpus+0x64/0xd0
[12704.164794]  rib#4: 000000000ef8e31d (&vcpu->mutex){+.+.}, at: lock_all_vcpus+0x64/0xd0
[12704.164827]  rib#5: 000000007a872093 (&vcpu->mutex){+.+.}, at: lock_all_vcpus+0x64/0xd0
[12704.164861] stack backtrace:
[12704.164878] CPU: 2 PID: 13968 Comm: qemu-system-aar Tainted: G        W         5.1.0-rc1-00008-g600025238f51-dirty rib#16
[12704.164887] Hardware name: rockchip evb_rk3399/evb_rk3399, BIOS 2019.04-rc3-00124-g2feec69fb1 03/15/2019
[12704.164896] Call trace:
[12704.164910]  dump_backtrace+0x0/0x138
[12704.164920]  show_stack+0x24/0x30
[12704.164934]  dump_stack+0xbc/0x104
[12704.164946]  lockdep_rcu_suspicious+0xcc/0x110
[12704.164958]  gfn_to_memslot+0x174/0x190
[12704.164969]  kvm_is_visible_gfn+0x28/0x70
[12704.164980]  vgic_its_check_id.isra.0+0xec/0x1e8
[12704.164991]  vgic_its_save_tables_v0+0x1ac/0x330
[12704.165001]  vgic_its_set_attr+0x298/0x3a0
[12704.165012]  kvm_device_ioctl_attr+0x9c/0xd8
[12704.165022]  kvm_device_ioctl+0x8c/0xf8
[12704.165035]  do_vfs_ioctl+0xc8/0x960
[12704.165045]  ksys_ioctl+0x8c/0xa0
[12704.165055]  __arm64_sys_ioctl+0x28/0x38
[12704.165067]  el0_svc_common+0xd8/0x138
[12704.165078]  el0_svc_handler+0x38/0x78
[12704.165089]  el0_svc+0x8/0xc

Make sure the lock is taken when doing this.

Fixes: bf30824 ("KVM: arm/arm64: VGIC/ITS: protect kvm_read_guest() calls with SRCU lock")
Reviewed-by: Eric Auger <[email protected]>
Signed-off-by: Marc Zyngier <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Apr 2, 2019
If we use "crashkernel=Y[@x]" and the start address is above 4G,
the arm64 kdump capture kernel may call memblock_alloc_low() failure
in request_standard_resources(). Replacing memblock_alloc_low() with
memblock_alloc().

[    0.000000] MEMBLOCK configuration:
[    0.000000]  memory size = 0x0000000040650000 reserved size = 0x0000000004db7f39
[    0.000000]  memory.cnt  = 0x6
[    0.000000]  memory[0x0]	[0x00000000395f0000-0x000000003968ffff], 0x00000000000a0000 bytes on node 0 flags: 0x4
[    0.000000]  memory[0x1]	[0x0000000039730000-0x000000003973ffff], 0x0000000000010000 bytes on node 0 flags: 0x4
[    0.000000]  memory[0x2]	[0x0000000039780000-0x000000003986ffff], 0x00000000000f0000 bytes on node 0 flags: 0x4
[    0.000000]  memory[0x3]	[0x0000000039890000-0x0000000039d0ffff], 0x0000000000480000 bytes on node 0 flags: 0x4
[    0.000000]  memory[0x4]	[0x000000003ed00000-0x000000003ed2ffff], 0x0000000000030000 bytes on node 0 flags: 0x4
[    0.000000]  memory[0x5]	[0x0000002040000000-0x000000207fffffff], 0x0000000040000000 bytes on node 0 flags: 0x0
[    0.000000]  reserved.cnt  = 0x7
[    0.000000]  reserved[0x0]	[0x0000002040080000-0x0000002041c4dfff], 0x0000000001bce000 bytes flags: 0x0
[    0.000000]  reserved[0x1]	[0x0000002041c53000-0x0000002042c203f8], 0x0000000000fcd3f9 bytes flags: 0x0
[    0.000000]  reserved[0x2]	[0x000000207da00000-0x000000207dbfffff], 0x0000000000200000 bytes flags: 0x0
[    0.000000]  reserved[0x3]	[0x000000207ddef000-0x000000207fbfffff], 0x0000000001e11000 bytes flags: 0x0
[    0.000000]  reserved[0x4]	[0x000000207fdf2b00-0x000000207fdfc03f], 0x0000000000009540 bytes flags: 0x0
[    0.000000]  reserved[0x5]	[0x000000207fdfd000-0x000000207ffff3ff], 0x0000000000202400 bytes flags: 0x0
[    0.000000]  reserved[0x6]	[0x000000207ffffe00-0x000000207fffffff], 0x0000000000000200 bytes flags: 0x0
[    0.000000] Kernel panic - not syncing: request_standard_resources: Failed to allocate 384 bytes
[    0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 5.1.0-next-20190321+ rib#4
[    0.000000] Call trace:
[    0.000000]  dump_backtrace+0x0/0x188
[    0.000000]  show_stack+0x24/0x30
[    0.000000]  dump_stack+0xa8/0xcc
[    0.000000]  panic+0x14c/0x31c
[    0.000000]  setup_arch+0x2b0/0x5e0
[    0.000000]  start_kernel+0x90/0x52c
[    0.000000] ---[ end Kernel panic - not syncing: request_standard_resources: Failed to allocate 384 bytes ]---

Link: https://www.spinics.net/lists/arm-kernel/msg715293.html
Signed-off-by: Chen Zhou <[email protected]>
Signed-off-by: Catalin Marinas <[email protected]>
djdeath pushed a commit to djdeath/linux that referenced this issue Apr 8, 2019
in workload creation routine, if any failure occurs, do not queue this
workload for delivery. if this failure is fatal, enter into failsafe
mode.

Fixes: 6d76303 ("drm/i915/gvt: Move common vGPU workload creation into scheduler.c")
Cc: [email protected] rib#4.19+
Cc: [email protected]
Signed-off-by: Yan Zhao <[email protected]>
Signed-off-by: Zhenyu Wang <[email protected]>
djdeath pushed a commit to djdeath/linux that referenced this issue Apr 8, 2019
shadow mm's pin count got increased in workload preparation phase, which
is after workload scanning.
it will get decreased in complete_current_workload() anyway after
workload completion.
Sometimes, if a workload meets a scanning error, its shadow mm pin count
will not get increased but will get decreased in the end.
This patch lets shadow mm's pin count not go below 0.

Fixes: 2707e44 ("drm/i915/gvt: vGPU graphics memory virtualization")
Cc: [email protected]
Cc: [email protected] rib#4.14+
Signed-off-by: Yan Zhao <[email protected]>
Signed-off-by: Zhenyu Wang <[email protected]>
djdeath pushed a commit to djdeath/linux that referenced this issue May 17, 2019
In NVMe's error handler, follows the typical steps of tearing down
hardware for recovering controller:

1) stop blk_mq hw queues
2) stop the real hw queues
3) cancel in-flight requests via
	blk_mq_tagset_busy_iter(tags, cancel_request, ...)
cancel_request():
	mark the request as abort
	blk_mq_complete_request(req);
4) destroy real hw queues

However, there may be race between rib#3 and rib#4, because blk_mq_complete_request()
may run q->mq_ops->complete(rq) remotelly and asynchronously, and
->complete(rq) may be run after rib#4.

This patch introduces blk_mq_complete_request_sync() for fixing the
above race.

Cc: Sagi Grimberg <[email protected]>
Cc: Bart Van Assche <[email protected]>
Cc: James Smart <[email protected]>
Cc: [email protected]
Reviewed-by: Keith Busch <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
Signed-off-by: Ming Lei <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
djdeath pushed a commit to djdeath/linux that referenced this issue May 17, 2019
Ido Schimmel says:

====================
mlxsw: Various fixes

This patchset contains various small fixes for mlxsw.

Patch rib#1 fixes a warning generated by switchdev core when the driver
fails to insert an MDB entry in the commit phase.

Patches rib#2-rib#4 fix a warning in check_flush_dependency() that can be
triggered when a work item in a WQ_MEM_RECLAIM workqueue tries to flush
a non-WQ_MEM_RECLAIM workqueue.

It seems that the semantics of the WQ_MEM_RECLAIM flag are not very
clear [1] and that various patches have been sent to remove it from
various workqueues throughout the kernel [2][3][4] in order to silence
the warning.

These patches do the same for the workqueues created by mlxsw that
probably should not have been created with this flag in the first place.

Patch rib#5 fixes a regression where an IP address cannot be assigned to a
VRF upper due to erroneous MAC validation check. Patch rib#6 adds a test
case.

Patch rib#7 adjusts Spectrum-2 shared buffer configuration to be compatible
with Spectrum-1. The problem and fix are described in detail in the
commit message.

Please consider patches rib#1-rib#5 for 5.0.y. I verified they apply cleanly.

[1] https://patchwork.kernel.org/patch/10791315/
[2] Commit ce162bf ("mac80211_hwsim: don't use WQ_MEM_RECLAIM")
[3] Commit 39baf10 ("IB/core: Fix use workqueue without WQ_MEM_RECLAIM")
[4] Commit 75215e5 ("iwcm: Don't allocate iwcm workqueue with WQ_MEM_RECLAIM")
====================

Signed-off-by: David S. Miller <[email protected]>
djdeath pushed a commit to djdeath/linux that referenced this issue May 17, 2019
Move ieee80211_tx_status_ext() outside of status_list lock section
in order to avoid locking dependency and possible deadlock reposed by
LOCKDEP in below warning.

Also do mt76_tx_status_lock() just before it's needed.

[  440.224832] WARNING: possible circular locking dependency detected
[  440.224833] 5.1.0-rc2+ rib#22 Not tainted
[  440.224834] ------------------------------------------------------
[  440.224835] kworker/u16:28/2362 is trying to acquire lock:
[  440.224836] 0000000089b8cacf (&(&q->lock)->rlock#2){+.-.}, at: mt76_wake_tx_queue+0x4c/0xb0 [mt76]
[  440.224842]
               but task is already holding lock:
[  440.224842] 000000002cfedc59 (&(&sta->lock)->rlock){+.-.}, at: ieee80211_stop_tx_ba_cb+0x32/0x1f0 [mac80211]
[  440.224863]
               which lock already depends on the new lock.

[  440.224863]
               the existing dependency chain (in reverse order) is:
[  440.224864]
               -> rib#3 (&(&sta->lock)->rlock){+.-.}:
[  440.224869]        _raw_spin_lock_bh+0x34/0x40
[  440.224880]        ieee80211_start_tx_ba_session+0xe4/0x3d0 [mac80211]
[  440.224894]        minstrel_ht_get_rate+0x45c/0x510 [mac80211]
[  440.224906]        rate_control_get_rate+0xc1/0x140 [mac80211]
[  440.224918]        ieee80211_tx_h_rate_ctrl+0x195/0x3c0 [mac80211]
[  440.224930]        ieee80211_xmit_fast+0x26d/0xa50 [mac80211]
[  440.224942]        __ieee80211_subif_start_xmit+0xfc/0x310 [mac80211]
[  440.224954]        ieee80211_subif_start_xmit+0x38/0x390 [mac80211]
[  440.224956]        dev_hard_start_xmit+0xb8/0x300
[  440.224957]        __dev_queue_xmit+0x7d4/0xbb0
[  440.224968]        ip6_finish_output2+0x246/0x860 [ipv6]
[  440.224978]        mld_sendpack+0x1bd/0x360 [ipv6]
[  440.224987]        mld_ifc_timer_expire+0x1a4/0x2f0 [ipv6]
[  440.224989]        call_timer_fn+0x89/0x2a0
[  440.224990]        run_timer_softirq+0x1bd/0x4d0
[  440.224992]        __do_softirq+0xdb/0x47c
[  440.224994]        irq_exit+0xfa/0x100
[  440.224996]        smp_apic_timer_interrupt+0x9a/0x220
[  440.224997]        apic_timer_interrupt+0xf/0x20
[  440.224999]        cpuidle_enter_state+0xc1/0x470
[  440.225000]        do_idle+0x21a/0x260
[  440.225001]        cpu_startup_entry+0x19/0x20
[  440.225004]        start_secondary+0x135/0x170
[  440.225006]        secondary_startup_64+0xa4/0xb0
[  440.225007]
               -> rib#2 (&(&sta->rate_ctrl_lock)->rlock){+.-.}:
[  440.225009]        _raw_spin_lock_bh+0x34/0x40
[  440.225022]        rate_control_tx_status+0x4f/0xb0 [mac80211]
[  440.225031]        ieee80211_tx_status_ext+0x142/0x1a0 [mac80211]
[  440.225035]        mt76x02_send_tx_status+0x2e4/0x340 [mt76x02_lib]
[  440.225037]        mt76x02_tx_status_data+0x31/0x40 [mt76x02_lib]
[  440.225040]        mt76u_tx_status_data+0x51/0xa0 [mt76_usb]
[  440.225042]        process_one_work+0x237/0x5d0
[  440.225043]        worker_thread+0x3c/0x390
[  440.225045]        kthread+0x11d/0x140
[  440.225046]        ret_from_fork+0x3a/0x50
[  440.225047]
               -> rib#1 (&(&list->lock)->rlock#8){+.-.}:
[  440.225049]        _raw_spin_lock_bh+0x34/0x40
[  440.225052]        mt76_tx_status_skb_add+0x51/0x100 [mt76]
[  440.225054]        mt76x02u_tx_prepare_skb+0xbd/0x116 [mt76x02_usb]
[  440.225056]        mt76u_tx_queue_skb+0x5f/0x180 [mt76_usb]
[  440.225058]        mt76_tx+0x93/0x190 [mt76]
[  440.225070]        ieee80211_tx_frags+0x148/0x210 [mac80211]
[  440.225081]        __ieee80211_tx+0x75/0x1b0 [mac80211]
[  440.225092]        ieee80211_tx+0xde/0x110 [mac80211]
[  440.225105]        __ieee80211_tx_skb_tid_band+0x72/0x90 [mac80211]
[  440.225122]        ieee80211_send_auth+0x1f3/0x360 [mac80211]
[  440.225141]        ieee80211_auth.cold.40+0x6c/0x100 [mac80211]
[  440.225156]        ieee80211_mgd_auth.cold.50+0x132/0x15f [mac80211]
[  440.225171]        cfg80211_mlme_auth+0x149/0x360 [cfg80211]
[  440.225181]        nl80211_authenticate+0x273/0x2e0 [cfg80211]
[  440.225183]        genl_family_rcv_msg+0x196/0x3a0
[  440.225184]        genl_rcv_msg+0x47/0x8e
[  440.225185]        netlink_rcv_skb+0x3a/0xf0
[  440.225187]        genl_rcv+0x24/0x40
[  440.225188]        netlink_unicast+0x16d/0x210
[  440.225189]        netlink_sendmsg+0x204/0x3b0
[  440.225191]        sock_sendmsg+0x36/0x40
[  440.225193]        ___sys_sendmsg+0x259/0x2b0
[  440.225194]        __sys_sendmsg+0x47/0x80
[  440.225196]        do_syscall_64+0x60/0x1f0
[  440.225197]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[  440.225198]
               -> #0 (&(&q->lock)->rlock#2){+.-.}:
[  440.225200]        lock_acquire+0xb9/0x1a0
[  440.225202]        _raw_spin_lock_bh+0x34/0x40
[  440.225204]        mt76_wake_tx_queue+0x4c/0xb0 [mt76]
[  440.225215]        ieee80211_agg_start_txq+0xe8/0x2b0 [mac80211]
[  440.225225]        ieee80211_stop_tx_ba_cb+0xb8/0x1f0 [mac80211]
[  440.225235]        ieee80211_ba_session_work+0x1c1/0x2f0 [mac80211]
[  440.225236]        process_one_work+0x237/0x5d0
[  440.225237]        worker_thread+0x3c/0x390
[  440.225239]        kthread+0x11d/0x140
[  440.225240]        ret_from_fork+0x3a/0x50
[  440.225240]
               other info that might help us debug this:

[  440.225241] Chain exists of:
                 &(&q->lock)->rlock#2 --> &(&sta->rate_ctrl_lock)->rlock --> &(&sta->lock)->rlock

[  440.225243]  Possible unsafe locking scenario:

[  440.225244]        CPU0                    CPU1
[  440.225244]        ----                    ----
[  440.225245]   lock(&(&sta->lock)->rlock);
[  440.225245]                                lock(&(&sta->rate_ctrl_lock)->rlock);
[  440.225246]                                lock(&(&sta->lock)->rlock);
[  440.225247]   lock(&(&q->lock)->rlock#2);
[  440.225248]
                *** DEADLOCK ***

[  440.225249] 5 locks held by kworker/u16:28/2362:
[  440.225250]  #0: 0000000048fcd291 ((wq_completion)phy0){+.+.}, at: process_one_work+0x1b5/0x5d0
[  440.225252]  rib#1: 00000000f1c6828f ((work_completion)(&sta->ampdu_mlme.work)){+.+.}, at: process_one_work+0x1b5/0x5d0
[  440.225254]  rib#2: 00000000433d2b2c (&sta->ampdu_mlme.mtx){+.+.}, at: ieee80211_ba_session_work+0x5c/0x2f0 [mac80211]
[  440.225265]  rib#3: 000000002cfedc59 (&(&sta->lock)->rlock){+.-.}, at: ieee80211_stop_tx_ba_cb+0x32/0x1f0 [mac80211]
[  440.225276]  rib#4: 000000009d7b9a44 (rcu_read_lock){....}, at: ieee80211_agg_start_txq+0x33/0x2b0 [mac80211]
[  440.225286]
               stack backtrace:
[  440.225288] CPU: 2 PID: 2362 Comm: kworker/u16:28 Not tainted 5.1.0-rc2+ rib#22
[  440.225289] Hardware name: LENOVO 20KGS23S0P/20KGS23S0P, BIOS N23ET55W (1.30 ) 08/31/2018
[  440.225300] Workqueue: phy0 ieee80211_ba_session_work [mac80211]
[  440.225301] Call Trace:
[  440.225304]  dump_stack+0x85/0xc0
[  440.225306]  print_circular_bug.isra.38.cold.58+0x15c/0x195
[  440.225307]  check_prev_add.constprop.48+0x5f0/0xc00
[  440.225309]  ? check_prev_add.constprop.48+0x39d/0xc00
[  440.225311]  ? __lock_acquire+0x41d/0x1100
[  440.225312]  __lock_acquire+0xd98/0x1100
[  440.225313]  ? __lock_acquire+0x41d/0x1100
[  440.225315]  lock_acquire+0xb9/0x1a0
[  440.225317]  ? mt76_wake_tx_queue+0x4c/0xb0 [mt76]
[  440.225319]  _raw_spin_lock_bh+0x34/0x40
[  440.225321]  ? mt76_wake_tx_queue+0x4c/0xb0 [mt76]
[  440.225323]  mt76_wake_tx_queue+0x4c/0xb0 [mt76]
[  440.225334]  ieee80211_agg_start_txq+0xe8/0x2b0 [mac80211]
[  440.225344]  ieee80211_stop_tx_ba_cb+0xb8/0x1f0 [mac80211]
[  440.225354]  ieee80211_ba_session_work+0x1c1/0x2f0 [mac80211]
[  440.225356]  process_one_work+0x237/0x5d0
[  440.225358]  worker_thread+0x3c/0x390
[  440.225359]  ? wq_calc_node_cpumask+0x70/0x70
[  440.225360]  kthread+0x11d/0x140
[  440.225362]  ? kthread_create_on_node+0x40/0x40
[  440.225363]  ret_from_fork+0x3a/0x50

Cc: [email protected]
Fixes: 88046b2 ("mt76: add support for reporting tx status with skb")
Signed-off-by: Stanislaw Gruszka <[email protected]>
Acked-by: Felix Fietkau <[email protected]>
Signed-off-by: Kalle Valo <[email protected]>
djdeath pushed a commit to djdeath/linux that referenced this issue May 17, 2019
By calling maps__insert() we assume to get 2 references on the map,
which we relese within maps__remove call.

However if there's already same map name, we currently don't bump the
reference and can crash, like:

  Program received signal SIGABRT, Aborted.
  0x00007ffff75e60f5 in raise () from /lib64/libc.so.6

  (gdb) bt
  #0  0x00007ffff75e60f5 in raise () from /lib64/libc.so.6
  rib#1  0x00007ffff75d0895 in abort () from /lib64/libc.so.6
  rib#2  0x00007ffff75d0769 in __assert_fail_base.cold () from /lib64/libc.so.6
  rib#3  0x00007ffff75de596 in __assert_fail () from /lib64/libc.so.6
  rib#4  0x00000000004fc006 in refcount_sub_and_test (i=1, r=0x1224e88) at tools/include/linux/refcount.h:131
  rib#5  refcount_dec_and_test (r=0x1224e88) at tools/include/linux/refcount.h:148
  rib#6  map__put (map=0x1224df0) at util/map.c:299
  rib#7  0x00000000004fdb95 in __maps__remove (map=0x1224df0, maps=0xb17d80) at util/map.c:953
  rib#8  maps__remove (maps=0xb17d80, map=0x1224df0) at util/map.c:959
  rib#9  0x00000000004f7d8a in map_groups__remove (map=<optimized out>, mg=<optimized out>) at util/map_groups.h:65
  rib#10 machine__process_ksymbol_unregister (sample=<optimized out>, event=0x7ffff7279670, machine=<optimized out>) at util/machine.c:728
  rib#11 machine__process_ksymbol (machine=<optimized out>, event=0x7ffff7279670, sample=<optimized out>) at util/machine.c:741
  rib#12 0x00000000004fffbb in perf_session__deliver_event (session=0xb11390, event=0x7ffff7279670, tool=0x7fffffffc7b0, file_offset=13936) at util/session.c:1362
  rib#13 0x00000000005039bb in do_flush (show_progress=false, oe=0xb17e80) at util/ordered-events.c:243
  rib#14 __ordered_events__flush (oe=0xb17e80, how=OE_FLUSH__ROUND, timestamp=<optimized out>) at util/ordered-events.c:322
  rib#15 0x00000000005005e4 in perf_session__process_user_event (session=session@entry=0xb11390, event=event@entry=0x7ffff72a4af8,
  ...

Add the map to the list and getting the reference event if we find the
map with same name.

Signed-off-by: Jiri Olsa <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Alexei Starovoitov <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Daniel Borkmann <[email protected]>
Cc: Eric Saint-Etienne <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Song Liu <[email protected]>
Fixes: 1e62856 ("perf symbols: Fix slowness due to -ffunction-section")
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
djdeath pushed a commit to djdeath/linux that referenced this issue May 17, 2019
[    3.707412] Unable to handle kernel NULL pointer dereference at virtual address 0000009c
[    3.714511] pgd = (ptrval)
[    3.722742] [0000009c] *pgd=00000000
[    3.725238] Internal error: Oops: 5 [rib#1] PREEMPT SMP ARM
[    3.728968] Modules linked in:
[    3.734265] CPU: 3 PID: 112 Comm: kworker/3:2 Tainted: G        W         5.0.0-rc7-00183-g06a1c31df9eb rib#4
[    3.737142] Hardware name: Generic DT based system
[    3.746778] Workqueue: events deferred_probe_work_func
[    3.751542] PC is at msm_gem_map_vma+0x3c/0xac
[    3.756669] LR is at msm_gem_get_and_pin_iova+0xd8/0x134
[    3.761086] pc : [<c07d3b7c>]    lr : [<c07d14f8>]    psr: 60000013
[    3.766560] sp : ee297be8  ip : ed9ab1c0  fp : ed93b800
[    3.772546] r10: ee35e180  r9 : 00000000  r8 : ee297c80
[    3.777752] r7 : 00000000  r6 : 7c100000  r5 : 00000000  r4 : ee35e180
[    3.782968] r3 : 00000001  r2 : 00000003  r1 : ee35e180  r0 : 00000000
[    3.789562] Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
[    3.796079] Control: 10c5787d  Table: 2e3a806  DAC: 00000051
[    3.803282] Process kworker/3:2 (pid: 112, stack limit = 0x(ptrval))
[    3.809006] Stack: (0xee297be8 to 0xee298000)
[    3.815445] 7be0:                   00000000 c1108c48 eda8c000 00000003 eda8c0fc c1108c48
[    3.819715] 7c00: eda8c000 00000003 eda8c0fc c07d14f8 00000001 c07d1100 7c100000 00000000
[    3.827873] 7c20: eda8c000 bb7ffb78 00000000 eda8c000 00000000 00000000 c0c8b1d4 ee3bfa00
[    3.836037] 7c40: ee3b9800 c07d1684 00000000 c1108c48 ee0d7810 ee3b9800 c0c8b1d4 c07d222c
[    3.844193] 7c60: ee3bfd84 ee297c80 00000000 c0b1d5b0 ee3bfc40 c07dcfd8 ee3bfd84 ee297c80
[    3.852357] 7c80: 0000006d ee3bfc40 ee0d7810 bb7ffb78 c0c8b1d4 00000000 ee3bfc40 c07ddb48
[    3.860516] 7ca0: 00002004 c0eba384 ee3bfc40 c079eba0 ee3bd040 ee3b9800 00000001 ed93b800
[    3.868673] 7cc0: ed9aa100 c07db7e8 ee3bf240 ed9a6500 00000001 ee3b9800 ee3bf2d4 c07a0a30
[    3.876834] 7ce0: ed93b800 7d100000 c1108c48 ee0d7610 ee3b9800 ed93b800 c1108c48 00000000
[    3.884991] 7d00: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
[    3.893151] 7d20: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 bb7ffb78
[    3.901310] 7d40: c12113c4 ed93b800 ee3b9800 c1108c48 ee9eec10 00000000 ed93b800 7d100000
[    3.909472] 7d60: eff7b000 c07cf748 7d100000 00000000 c0e9a350 c0b1d5b0 c12113c4 c0961e40
[    3.917633] 7d80: c12113c4 40000113 eeff4bec c0ebe004 00000019 c0b1d230 ee9eeda8 60000113
[    3.925791] 7da0: ee35d300 ee9eeda8 c07ce260 bb7ffb78 c07ce260 ee35d2c 00000028 00000002
[    3.933950] 7dc0: eeb76280 c118f884 ee0be640 c11c6128 c07ce260 c07ea4ac 00000000 c0962b48
[    3.942108] 7de0: c118f868 00000001 c0ebbc98 ee35d2c 00000000 eeb76280 00000000 c118f87c
[    3.950270] 7e00: ee35d2c 00000000 c11c63e0 c118f694 00000019 c07ea5d0 ee0d7810 00000000
[    3.958430] 7e20: c118f694 00000000 00000000 c07f2b0c c120f55c ee0d7810 c120f560 00000000
[    3.966590] 7e40: 00000000 c07f08c4 c07f0e8c ee0d7810 c11ba3d0 ee0d7810 c118f694 c07f0e8c
[    3.974748] 7e60: c1108c48 00000001 c0ebc3cc c11c63f8 c11ba3d0 c07f0c08 00000001 c07f2f8c
[    3.982908] 7e80: c118f694 00000000 ee297ed4 c07f0e8c c1108c48 00000001 c0ebc3cc c11c63f8
[    3.991068] 7ea0: c11ba3d0 c07ee8a0 c11ba3d0 ee82686c ee0baf38 bb7ffb78 ee0d7810 ee0d7810
[    3.999227] 7ec0: c1108c48 ee0d7844 c118faac c07f05b0 ee0d7810 ee0d7810 00000001 bb7ffb78
[    4.007389] 7ee0: ee0d7810 ee0d7810 c118fd18 c118faac c11c63e0 c07ef7d0 ee0d7810 c118fa90
[    4.015548] 7f00: c118fa90 c07efd68 c118fac8 ee27fe00 eefd9c80 eefdcd00 00000000 c118facc
[    4.023708] 7f20: 00000000 c033c038 eefd9c80 eefd9c80 00000008 ee27fe00 ee27fe14 eefd9c80
[    4.031866] 7f40: 00000008 c1103d00 eefd9c98 ee296000 eefd9c80 c033ce54 ee907eac c0b1d230
[    4.040026] 7f60: ee907eac eea24440 ee285000 00000000 ee296000 ee27fe00 c033ce24 eea2445c
[    4.048188] 7f80: ee907eac c0341db0 00000000 ee285000 c0341c8c 00000000 00000000 00000000
[    4.056346] 7fa0: 00000000 00000000 00000000 c03010e8 00000000 00000000 00000000 00000000
[    4.064505] 7fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
[    4.072665] 7fe0: 00000000 00000000 00000000 00000000 00000013 00000000 00000000 00000000
[    4.080828] [<c07d3b7c>] (msm_gem_map_vma) from [<c07d14f8>] (msm_gem_get_and_pin_iova+0xd8/0x134)
[    4.088983] [<c07d14f8>] (msm_gem_get_and_pin_iova) from [<c07d1684>] (_msm_gem_kernel_new+0x38/0xac)
[    4.097839] [<c07d1684>] (_msm_gem_kernel_new) from [<c07d222c>] (msm_gem_kernel_new+0x24/0x2c)
[    4.107130] [<c07d222c>] (msm_gem_kernel_new) from [<c07dcfd8>] (dsi_tx_buf_alloc_6g+0x44/0x90)
[    4.115631] [<c07dcfd8>] (dsi_tx_buf_alloc_6g) from [<c07ddb48>] (msm_dsi_host_modeset_init+0x80/0x104)
[    4.124313] [<c07ddb48>] (msm_dsi_host_modeset_init) from [<c07db7e8>] (msm_dsi_modeset_init+0x34/0x1c0)
[    4.133691] [<c07db7e8>] (msm_dsi_modeset_init) from [<c07a0a30>] (mdp5_kms_init+0x764/0x7e0)
[    4.143409] [<c07a0a30>] (mdp5_kms_init) from [<c07cf748>] (msm_drm_bind+0x56c/0x740)
[    4.151824] [<c07cf748>] (msm_drm_bind) from [<c07ea4ac>] (try_to_bring_up_master+0x238/0x2b4)
[    4.159636] [<c07ea4ac>] (try_to_bring_up_master) from [<c07ea5d0>] (component_add+0xa8/0x170)
[    4.168146] [<c07ea5d0>] (component_add) from [<c07f2b0c>] (platform_drv_probe+0x48/0x9c)
[    4.176737] [<c07f2b0c>] (platform_drv_probe) from [<c07f08c4>] (really_probe+0x278/0x404)
[    4.184981] [<c07f08c4>] (really_probe) from [<c07f0c08>] (driver_probe_device+0x78/0x1c0)
[    4.193147] [<c07f0c08>] (driver_probe_device) from [<c07ee8a0>] (bus_for_each_drv+0x74/0xb8)
[    4.201389] [<c07ee8a0>] (bus_for_each_drv) from [<c07f05b0>] (__device_attach+0xd0/0x164)
[    4.209984] [<c07f05b0>] (__device_attach) from [<c07ef7d0>] (bus_probe_device+0x84/0x8c)
[    4.218143] [<c07ef7d0>] (bus_probe_device) from [<c07efd68>] (deferred_probe_work_func+0x48/0xc4)
[    4.226398] [<c07efd68>] (deferred_probe_work_func) from [<c033c038>] (process_one_work+0x204/0x574)
[    4.235254] [<c033c038>] (process_one_work) from [<c033ce54>] (worker_thread+0x30/0x560)
[    4.244534] [<c033ce54>] (worker_thread) from [<c0341db0>] (kthread+0x124/0x154)
[    4.252606] [<c0341db0>] (kthread) from [<c03010e8>] (ret_from_fork+0x14/0x2c)
[    4.259966] Exception stack(0xee297fb0 to 0xee297ff8)
[    4.266998] 7fa0:                                     00000000 00000000 00000000 00000000
[    4.272143] 7fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
[    4.280297] 7fe0: 00000000 00000000 00000000 00000000 00000013 00000000
[    4.288451] Code: e5813080 1a000013 e3a03001 e5c4307c (e590009c)
[    4.294933] ---[ end trace 18729cc2bca2b4b3 ]---

Signed-off-by: Luca Weiss <[email protected]>
Signed-off-by: Rob Clark <[email protected]>
Signed-off-by: Rob Clark <[email protected]>
djdeath pushed a commit to djdeath/linux that referenced this issue May 17, 2019
The first kmemleak_scan() call after boot would trigger the crash below
because this callpath:

  kernel_init
    free_initmem
      mem_encrypt_free_decrypted_mem
        free_init_pages

unmaps memory inside the .bss when DEBUG_PAGEALLOC=y.

kmemleak_init() will register the .data/.bss sections and then
kmemleak_scan() will scan those addresses and dereference them looking
for pointer references. If free_init_pages() frees and unmaps pages in
those sections, kmemleak_scan() will crash if referencing one of those
addresses:

  BUG: unable to handle kernel paging request at ffffffffbd402000
  CPU: 12 PID: 325 Comm: kmemleak Not tainted 5.1.0-rc4+ rib#4
  RIP: 0010:scan_block
  Call Trace:
   scan_gray_list
   kmemleak_scan
   kmemleak_scan_thread
   kthread
   ret_from_fork

Since kmemleak_free_part() is tolerant to unknown objects (not tracked
by kmemleak), it is fine to call it from free_init_pages() even if not
all address ranges passed to this function are known to kmemleak.

 [ bp: Massage. ]

Fixes: b3f0907 ("x86/mm: Add .bss..decrypted section to hold shared variables")
Signed-off-by: Qian Cai <[email protected]>
Signed-off-by: Borislav Petkov <[email protected]>
Reviewed-by: Catalin Marinas <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Brijesh Singh <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: x86-ml <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]
djdeath pushed a commit to djdeath/linux that referenced this issue May 17, 2019
This is the much more correct fix for my earlier attempt at:

https://lkml.org/lkml/2018/12/10/118

Short recap:

- There's not actually a locking issue, it's just lockdep being a bit
  too eager to complain about a possible deadlock.

- Contrary to what I claimed the real problem is recursion on
  kn->count. Greg pointed me at sysfs_break_active_protection(), used
  by the scsi subsystem to allow a sysfs file to unbind itself. That
  would be a real deadlock, which isn't what's happening here. Also,
  breaking the active protection means we'd need to manually handle
  all the lifetime fun.

- With Rafael we discussed the task_work approach, which kinda works,
  but has two downsides: It's a functional change for a lockdep
  annotation issue, and it won't work for the bind file (which needs
  to get the errno from the driver load function back to userspace).

- Greg also asked why this never showed up: To hit this you need to
  unregister a 2nd driver from the unload code of your first driver. I
  guess only gpus do that. The bug has always been there, but only
  with a recent patch series did we add more locks so that lockdep
  built a chain from unbinding the snd-hda driver to the
  acpi_video_unregister call.

Full lockdep splat:

[12301.898799] ============================================
[12301.898805] WARNING: possible recursive locking detected
[12301.898811] 4.20.0-rc7+ torvalds#84 Not tainted
[12301.898815] --------------------------------------------
[12301.898821] bash/5297 is trying to acquire lock:
[12301.898826] 00000000f61c6093 (kn->count#39){++++}, at: kernfs_remove_by_name_ns+0x3b/0x80
[12301.898841] but task is already holding lock:
[12301.898847] 000000005f634021 (kn->count#39){++++}, at: kernfs_fop_write+0xdc/0x190
[12301.898856] other info that might help us debug this:
[12301.898862]  Possible unsafe locking scenario:
[12301.898867]        CPU0
[12301.898870]        ----
[12301.898874]   lock(kn->count#39);
[12301.898879]   lock(kn->count#39);
[12301.898883] *** DEADLOCK ***
[12301.898891]  May be due to missing lock nesting notation
[12301.898899] 5 locks held by bash/5297:
[12301.898903]  #0: 00000000cd800e54 (sb_writers#4){.+.+}, at: vfs_write+0x17f/0x1b0
[12301.898915]  rib#1: 000000000465e7c2 (&of->mutex){+.+.}, at: kernfs_fop_write+0xd3/0x190
[12301.898925]  rib#2: 000000005f634021 (kn->count#39){++++}, at: kernfs_fop_write+0xdc/0x190
[12301.898936]  rib#3: 00000000414ef7ac (&dev->mutex){....}, at: device_release_driver_internal+0x34/0x240
[12301.898950]  rib#4: 000000003218fbdf (register_count_mutex){+.+.}, at: acpi_video_unregister+0xe/0x40
[12301.898960] stack backtrace:
[12301.898968] CPU: 1 PID: 5297 Comm: bash Not tainted 4.20.0-rc7+ torvalds#84
[12301.898974] Hardware name: Hewlett-Packard HP EliteBook 8460p/161C, BIOS 68SCF Ver. F.01 03/11/2011
[12301.898982] Call Trace:
[12301.898989]  dump_stack+0x67/0x9b
[12301.898997]  __lock_acquire+0x6ad/0x1410
[12301.899003]  ? kernfs_remove_by_name_ns+0x3b/0x80
[12301.899010]  ? find_held_lock+0x2d/0x90
[12301.899017]  ? mutex_spin_on_owner+0xe4/0x150
[12301.899023]  ? find_held_lock+0x2d/0x90
[12301.899030]  ? lock_acquire+0x90/0x180
[12301.899036]  lock_acquire+0x90/0x180
[12301.899042]  ? kernfs_remove_by_name_ns+0x3b/0x80
[12301.899049]  __kernfs_remove+0x296/0x310
[12301.899055]  ? kernfs_remove_by_name_ns+0x3b/0x80
[12301.899060]  ? kernfs_name_hash+0xd/0x80
[12301.899066]  ? kernfs_find_ns+0x6c/0x100
[12301.899073]  kernfs_remove_by_name_ns+0x3b/0x80
[12301.899080]  bus_remove_driver+0x92/0xa0
[12301.899085]  acpi_video_unregister+0x24/0x40
[12301.899127]  i915_driver_unload+0x42/0x130 [i915]
[12301.899160]  i915_pci_remove+0x19/0x30 [i915]
[12301.899169]  pci_device_remove+0x36/0xb0
[12301.899176]  device_release_driver_internal+0x185/0x240
[12301.899183]  unbind_store+0xaf/0x180
[12301.899189]  kernfs_fop_write+0x104/0x190
[12301.899195]  __vfs_write+0x31/0x180
[12301.899203]  ? rcu_read_lock_sched_held+0x6f/0x80
[12301.899209]  ? rcu_sync_lockdep_assert+0x29/0x50
[12301.899216]  ? __sb_start_write+0x13c/0x1a0
[12301.899221]  ? vfs_write+0x17f/0x1b0
[12301.899227]  vfs_write+0xb9/0x1b0
[12301.899233]  ksys_write+0x50/0xc0
[12301.899239]  do_syscall_64+0x4b/0x180
[12301.899247]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[12301.899253] RIP: 0033:0x7f452ac7f7a4
[12301.899259] Code: 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 80 00 00 00 00 8b 05 aa f0 2c 00 48 63 ff 85 c0 75 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 f3 c3 66 90 55 53 48 89 d5 48 89 f3 48 83
[12301.899273] RSP: 002b:00007ffceafa6918 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[12301.899282] RAX: ffffffffffffffda RBX: 000000000000000d RCX: 00007f452ac7f7a4
[12301.899288] RDX: 000000000000000d RSI: 00005612a1abf7c0 RDI: 0000000000000001
[12301.899295] RBP: 00005612a1abf7c0 R08: 000000000000000a R09: 00005612a1c46730
[12301.899301] R10: 000000000000000a R11: 0000000000000246 R12: 000000000000000d
[12301.899308] R13: 0000000000000001 R14: 00007f452af4a740 R15: 000000000000000d

Locking around I've noticed that usb and i2c already handle similar
recursion problems, where a sysfs file can unbind the same type of
sysfs somewhere else in the hierarchy. Relevant commits are:

commit 356c05d
Author: Alan Stern <[email protected]>
Date:   Mon May 14 13:30:03 2012 -0400

    sysfs: get rid of some lockdep false positives

commit e9b526f
Author: Alexander Sverdlin <[email protected]>
Date:   Fri May 17 14:56:35 2013 +0200

    i2c: suppress lockdep warning on delete_device

Implement the same trick for driver bind/unbind.

v2: Put the macro into bus.c (Greg).

Cc: "Rafael J. Wysocki" <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Ramalingam C <[email protected]>
Cc: Arend van Spriel <[email protected]>
Cc: Andy Shevchenko <[email protected]>
Cc: Geert Uytterhoeven <[email protected]>
Cc: Bartosz Golaszewski <[email protected]>
Cc: Heikki Krogerus <[email protected]>
Cc: Vivek Gautam <[email protected]>
Cc: Joe Perches <[email protected]>
Signed-off-by: Daniel Vetter <[email protected]>

Note that Greg already merged this, so this should drop out as soon as
we've moved forward past 4.21-rc1.
-Daniel
djdeath pushed a commit to djdeath/linux that referenced this issue Jun 12, 2019
…text

stub_probe() and stub_disconnect() call functions which could call
sleeping function in invalid context whil holding busid_lock.

Fix the problem by refining the lock holds to short critical sections
to change the busid_priv fields. This fix restructures the code to
limit the lock holds in stub_probe() and stub_disconnect().

stub_probe():

[15217.927028] BUG: sleeping function called from invalid context at mm/slab.h:418
[15217.927038] in_atomic(): 1, irqs_disabled(): 0, pid: 29087, name: usbip
[15217.927044] 5 locks held by usbip/29087:
[15217.927047]  #0: 0000000091647f28 (sb_writers#6){....}, at: vfs_write+0x191/0x1c0
[15217.927062]  rib#1: 000000008f9ba75b (&of->mutex){....}, at: kernfs_fop_write+0xf7/0x1b0
[15217.927072]  rib#2: 00000000872e5b4b (&dev->mutex){....}, at: __device_driver_lock+0x3b/0x50
[15217.927082]  rib#3: 00000000e74ececc (&dev->mutex){....}, at: __device_driver_lock+0x46/0x50
[15217.927090]  rib#4: 00000000b20abbe0 (&(&busid_table[i].busid_lock)->rlock){....}, at: get_busid_priv+0x48/0x60 [usbip_host]
[15217.927103] CPU: 3 PID: 29087 Comm: usbip Tainted: G        W         5.1.0-rc6+ torvalds#40
[15217.927106] Hardware name: Dell Inc. OptiPlex 790/0HY9JP, BIOS A18 09/24/2013
[15217.927109] Call Trace:
[15217.927118]  dump_stack+0x63/0x85
[15217.927127]  ___might_sleep+0xff/0x120
[15217.927133]  __might_sleep+0x4a/0x80
[15217.927143]  kmem_cache_alloc_trace+0x1aa/0x210
[15217.927156]  stub_probe+0xe8/0x440 [usbip_host]
[15217.927171]  usb_probe_device+0x34/0x70

stub_disconnect():

[15279.182478] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:908
[15279.182487] in_atomic(): 1, irqs_disabled(): 0, pid: 29114, name: usbip
[15279.182492] 5 locks held by usbip/29114:
[15279.182494]  #0: 0000000091647f28 (sb_writers#6){....}, at: vfs_write+0x191/0x1c0
[15279.182506]  rib#1: 00000000702cf0f3 (&of->mutex){....}, at: kernfs_fop_write+0xf7/0x1b0
[15279.182514]  rib#2: 00000000872e5b4b (&dev->mutex){....}, at: __device_driver_lock+0x3b/0x50
[15279.182522]  rib#3: 00000000e74ececc (&dev->mutex){....}, at: __device_driver_lock+0x46/0x50
[15279.182529]  rib#4: 00000000b20abbe0 (&(&busid_table[i].busid_lock)->rlock){....}, at: get_busid_priv+0x48/0x60 [usbip_host]
[15279.182541] CPU: 0 PID: 29114 Comm: usbip Tainted: G        W         5.1.0-rc6+ torvalds#40
[15279.182543] Hardware name: Dell Inc. OptiPlex 790/0HY9JP, BIOS A18 09/24/2013
[15279.182546] Call Trace:
[15279.182554]  dump_stack+0x63/0x85
[15279.182561]  ___might_sleep+0xff/0x120
[15279.182566]  __might_sleep+0x4a/0x80
[15279.182574]  __mutex_lock+0x55/0x950
[15279.182582]  ? get_busid_priv+0x48/0x60 [usbip_host]
[15279.182587]  ? reacquire_held_locks+0xec/0x1a0
[15279.182591]  ? get_busid_priv+0x48/0x60 [usbip_host]
[15279.182597]  ? find_held_lock+0x94/0xa0
[15279.182609]  mutex_lock_nested+0x1b/0x20
[15279.182614]  ? mutex_lock_nested+0x1b/0x20
[15279.182618]  kernfs_remove_by_name_ns+0x2a/0x90
[15279.182625]  sysfs_remove_file_ns+0x15/0x20
[15279.182629]  device_remove_file+0x19/0x20
[15279.182634]  stub_disconnect+0x6d/0x180 [usbip_host]
[15279.182643]  usb_unbind_device+0x27/0x60

Signed-off-by: Shuah Khan <[email protected]>
Cc: stable <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
djdeath pushed a commit to djdeath/linux that referenced this issue Jun 12, 2019
…rupts

The passthrough interrupts are defined at the host level and their IRQ
data should not be cleared unless specifically deconfigured (shutdown)
by the host. They differ from the IPI interrupts which are allocated
by the XIVE KVM device and reserved to the guest usage only.

This fixes a host crash when destroying a VM in which a PCI adapter
was passed-through. In this case, the interrupt is cleared and freed
by the KVM device and then shutdown by vfio at the host level.

[ 1007.360265] BUG: Kernel NULL pointer dereference at 0x00000d00
[ 1007.360285] Faulting instruction address: 0xc00000000009da34
[ 1007.360296] Oops: Kernel access of bad area, sig: 7 [rib#1]
[ 1007.360303] LE PAGE_SIZE=64K MMU=Radix MMU=Hash SMP NR_CPUS=2048 NUMA PowerNV
[ 1007.360314] Modules linked in: vhost_net vhost iptable_mangle ipt_MASQUERADE iptable_nat nf_nat xt_conntrack nf_conntrack nf_defrag_ipv4 ipt_REJECT nf_reject_ipv4 tun bridge stp llc kvm_hv kvm xt_tcpudp iptable_filter squashfs fuse binfmt_misc vmx_crypto ib_iser rdma_cm iw_cm ib_cm libiscsi scsi_transport_iscsi nfsd ip_tables x_tables autofs4 btrfs zstd_decompress zstd_compress lzo_compress raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq multipath mlx5_ib ib_uverbs ib_core crc32c_vpmsum mlx5_core
[ 1007.360425] CPU: 9 PID: 15576 Comm: CPU 18/KVM Kdump: loaded Not tainted 5.1.0-gad7e7d0ef rib#4
[ 1007.360454] NIP:  c00000000009da34 LR: c00000000009e50c CTR: c00000000009e5d0
[ 1007.360482] REGS: c000007f24ccf330 TRAP: 0300   Not tainted  (5.1.0-gad7e7d0ef)
[ 1007.360500] MSR:  900000000280b033 <SF,HV,VEC,VSX,EE,FP,ME,IR,DR,RI,LE>  CR: 24002484  XER: 00000000
[ 1007.360532] CFAR: c00000000009da10 DAR: 0000000000000d00 DSISR: 00080000 IRQMASK: 1
[ 1007.360532] GPR00: c00000000009e62c c000007f24ccf5c0 c000000001510600 c000007fe7f947c0
[ 1007.360532] GPR04: 0000000000000d00 0000000000000000 0000000000000000 c000005eff02d200
[ 1007.360532] GPR08: 0000000000400000 0000000000000000 0000000000000000 fffffffffffffffd
[ 1007.360532] GPR12: c00000000009e5d0 c000007fffff7b00 0000000000000031 000000012c345718
[ 1007.360532] GPR16: 0000000000000000 0000000000000008 0000000000418004 0000000000040100
[ 1007.360532] GPR20: 0000000000000000 0000000008430000 00000000003c0000 0000000000000027
[ 1007.360532] GPR24: 00000000000000ff 0000000000000000 00000000000000ff c000007faa90d98c
[ 1007.360532] GPR28: c000007faa90da40 00000000000fe040 ffffffffffffffff c000007fe7f947c0
[ 1007.360689] NIP [c00000000009da34] xive_esb_read+0x34/0x120
[ 1007.360706] LR [c00000000009e50c] xive_do_source_set_mask.part.0+0x2c/0x50
[ 1007.360732] Call Trace:
[ 1007.360738] [c000007f24ccf5c0] [c000000000a6383c] snooze_loop+0x15c/0x270 (unreliable)
[ 1007.360775] [c000007f24ccf5f0] [c00000000009e62c] xive_irq_shutdown+0x5c/0xe0
[ 1007.360795] [c000007f24ccf630] [c00000000019e4a0] irq_shutdown+0x60/0xe0
[ 1007.360813] [c000007f24ccf660] [c000000000198c44] __free_irq+0x3a4/0x420
[ 1007.360831] [c000007f24ccf700] [c000000000198dc8] free_irq+0x78/0xe0
[ 1007.360849] [c000007f24ccf730] [c00000000096c5a8] vfio_msi_set_vector_signal+0xa8/0x350
[ 1007.360878] [c000007f24ccf7f0] [c00000000096c938] vfio_msi_set_block+0xe8/0x1e0
[ 1007.360899] [c000007f24ccf850] [c00000000096cae0] vfio_msi_disable+0xb0/0x110
[ 1007.360912] [c000007f24ccf8a0] [c00000000096cd04] vfio_pci_set_msi_trigger+0x1c4/0x3d0
[ 1007.360922] [c000007f24ccf910] [c00000000096d910] vfio_pci_set_irqs_ioctl+0xa0/0x170
[ 1007.360941] [c000007f24ccf930] [c00000000096b400] vfio_pci_disable+0x80/0x5e0
[ 1007.360963] [c000007f24ccfa10] [c00000000096b9bc] vfio_pci_release+0x5c/0x90
[ 1007.360991] [c000007f24ccfa40] [c000000000963a9c] vfio_device_fops_release+0x3c/0x70
[ 1007.361012] [c000007f24ccfa70] [c0000000003b5668] __fput+0xc8/0x2b0
[ 1007.361040] [c000007f24ccfac0] [c0000000001409b0] task_work_run+0x140/0x1b0
[ 1007.361059] [c000007f24ccfb20] [c000000000118f8c] do_exit+0x3ac/0xd00
[ 1007.361076] [c000007f24ccfc00] [c0000000001199b0] do_group_exit+0x60/0x100
[ 1007.361094] [c000007f24ccfc40] [c00000000012b514] get_signal+0x1a4/0x8f0
[ 1007.361112] [c000007f24ccfd30] [c000000000021cc8] do_notify_resume+0x1a8/0x430
[ 1007.361141] [c000007f24ccfe20] [c00000000000e444] ret_from_except_lite+0x70/0x74
[ 1007.361159] Instruction dump:
[ 1007.361175] 38422c00 e9230000 712a0004 41820010 548a2036 7d442378 78840020 71290020
[ 1007.361194] 4082004c e9230010 7c892214 7c0004ac <e9240000> 0c090000 4c00012c 792a0022

Cc: [email protected] # v4.12+
Fixes: 5af5099 ("KVM: PPC: Book3S HV: Native usage of the XIVE interrupt controller")
Signed-off-by: Cédric Le Goater <[email protected]>
Signed-off-by: Greg Kurz <[email protected]>
Signed-off-by: Paul Mackerras <[email protected]>
djdeath pushed a commit to djdeath/linux that referenced this issue Jun 12, 2019
Commit b7dbcc0 "NFSv4.1: Fix a race where CB_NOTIFY_LOCK fails to wake a waiter"
found this bug. However it didn't fix it.

This commit replaces schedule_timeout() with wait_woken() and
default_wake_function() with woken_wake_function() in function
nfs4_retry_setlk() and nfs4_wake_lock_waiter(). wait_woken() uses
memory barriers in its implementation to avoid potential race condition
when putting a process into sleeping state and then waking it up.

Fixes: a1d617d ("nfs: allow blocking locks to be awoken by lock callbacks")
Cc: [email protected] rib#4.9+
Signed-off-by: Yihao Wu <[email protected]>
Reviewed-by: Jeff Layton <[email protected]>
Signed-off-by: Anna Schumaker <[email protected]>
djdeath pushed a commit to djdeath/linux that referenced this issue Jun 12, 2019
When a waiter is waked by CB_NOTIFY_LOCK, it will retry
nfs4_proc_setlk(). The waiter may fail to nfs4_proc_setlk() and sleep
again. However, the waiter is already removed from clp->cl_lock_waitq
when handling CB_NOTIFY_LOCK in nfs4_wake_lock_waiter(). So any
subsequent CB_NOTIFY_LOCK won't wake this waiter anymore. We should
put the waiter back to clp->cl_lock_waitq before retrying.

Cc: [email protected] rib#4.9+
Signed-off-by: Yihao Wu <[email protected]>
Reviewed-by: Jeff Layton <[email protected]>
Signed-off-by: Anna Schumaker <[email protected]>
djdeath pushed a commit to djdeath/linux that referenced this issue Jul 9, 2019
ifmsh->csa is an RCU-protected pointer. The writer context
in ieee80211_mesh_finish_csa() is already mutually
exclusive with wdev->sdata.mtx, but the RCU checker did
not know this. Use rcu_dereference_protected() to avoid a
warning.

fixes the following warning:

[   12.519089] =============================
[   12.520042] WARNING: suspicious RCU usage
[   12.520652] 5.1.0-rc7-wt+ rib#16 Tainted: G        W
[   12.521409] -----------------------------
[   12.521972] net/mac80211/mesh.c:1223 suspicious rcu_dereference_check() usage!
[   12.522928] other info that might help us debug this:
[   12.523984] rcu_scheduler_active = 2, debug_locks = 1
[   12.524855] 5 locks held by kworker/u8:2/152:
[   12.525438]  #0: 00000000057be08c ((wq_completion)phy0){+.+.}, at: process_one_work+0x1a2/0x620
[   12.526607]  rib#1: 0000000059c6b07a ((work_completion)(&sdata->csa_finalize_work)){+.+.}, at: process_one_work+0x1a2/0x620
[   12.528001]  rib#2: 00000000f184ba7d (&wdev->mtx){+.+.}, at: ieee80211_csa_finalize_work+0x2f/0x90
[   12.529116]  rib#3: 00000000831a1f54 (&local->mtx){+.+.}, at: ieee80211_csa_finalize_work+0x47/0x90
[   12.530233]  rib#4: 00000000fd06f988 (&local->chanctx_mtx){+.+.}, at: ieee80211_csa_finalize_work+0x51/0x90

Signed-off-by: Thomas Pedersen <[email protected]>
Signed-off-by: Johannes Berg <[email protected]>
djdeath pushed a commit to djdeath/linux that referenced this issue Jul 9, 2019
Ido Schimmel says:

====================
mlxsw: Various fixes

This patchset contains various fixes for mlxsw.

Patch rib#1 fixes an hash polarization problem when a nexthop device is a
LAG device. This is caused by the fact that the same seed is used for
the LAG and ECMP hash functions.

Patch rib#2 fixes an issue in which the driver fails to refresh a nexthop
neighbour after it becomes dead. This prevents the nexthop from ever
being written to the adjacency table and used to forward traffic. Patch

Patch rib#4 fixes a wrong extraction of TOS value in flower offload code.
Patch rib#5 is a test case.

Patch rib#6 works around a buffer issue in Spectrum-2 by reducing the
default sizes of the shared buffer pools.

Patch rib#7 prevents prio-tagged packets from entering the switch when PVID
is removed from the bridge port.

Please consider patches rib#2, rib#4 and rib#6 for 5.1.y
====================

Signed-off-by: David S. Miller <[email protected]>
djdeath pushed a commit to djdeath/linux that referenced this issue Sep 17, 2019
Looks like the dma_sync calls don't do what we want on armv7 either.
Fixes:

  Unable to handle kernel paging request at virtual address 50001000
  pgd = (ptrval)
  [50001000] *pgd=00000000
  Internal error: Oops: 805 [rib#1] SMP ARM
  Modules linked in:
  CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.3.0-rc6-00271-g9f159ae07f07 rib#4
  Hardware name: Freescale i.MX53 (Device Tree Support)
  PC is at v7_dma_clean_range+0x20/0x38
  LR is at __dma_page_cpu_to_dev+0x28/0x90
  pc : [<c011c76c>]    lr : [<c01181c4>]    psr: 20000013
  sp : d80b5a88  ip : de96c000  fp : d840ce6c
  r10: 00000000  r9 : 00000001  r8 : d843e010
  r7 : 00000000  r6 : 00008000  r5 : ddb6c000  r4 : 00000000
  r3 : 0000003f  r2 : 00000040  r1 : 50008000  r0 : 50001000
  Flags: nzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
  Control: 10c5387d  Table: 70004019  DAC: 00000051
  Process swapper/0 (pid: 1, stack limit = 0x(ptrval))

Signed-off-by: Rob Clark <[email protected]>
Fixes: 3de433c ("drm/msm: Use the correct dma_sync calls in msm_gem")
Tested-by: Fabio Estevam <[email protected]>
djdeath pushed a commit to djdeath/linux that referenced this issue Mar 17, 2020
rmnet_get_port() internally calls rcu_dereference_rtnl(),
which checks RTNL.
But rmnet_get_port() could be called by packet path.
The packet path is not protected by RTNL.
So, the suspicious RCU usage problem occurs.

Test commands:
    modprobe rmnet
    ip netns add nst
    ip link add veth0 type veth peer name veth1
    ip link set veth1 netns nst
    ip link add rmnet0 link veth0 type rmnet mux_id 1
    ip netns exec nst ip link add rmnet1 link veth1 type rmnet mux_id 1
    ip netns exec nst ip link set veth1 up
    ip netns exec nst ip link set rmnet1 up
    ip netns exec nst ip a a 192.168.100.2/24 dev rmnet1
    ip link set veth0 up
    ip link set rmnet0 up
    ip a a 192.168.100.1/24 dev rmnet0
    ping 192.168.100.2

Splat looks like:
[  146.630958][ T1174] WARNING: suspicious RCU usage
[  146.631735][ T1174] 5.6.0-rc1+ torvalds#447 Not tainted
[  146.632387][ T1174] -----------------------------
[  146.633151][ T1174] drivers/net/ethernet/qualcomm/rmnet/rmnet_config.c:386 suspicious rcu_dereference_check() !
[  146.634742][ T1174]
[  146.634742][ T1174] other info that might help us debug this:
[  146.634742][ T1174]
[  146.645992][ T1174]
[  146.645992][ T1174] rcu_scheduler_active = 2, debug_locks = 1
[  146.646937][ T1174] 5 locks held by ping/1174:
[  146.647609][ T1174]  #0: ffff8880c31dea70 (sk_lock-AF_INET){+.+.}, at: raw_sendmsg+0xab8/0x2980
[  146.662463][ T1174]  rib#1: ffffffff93925660 (rcu_read_lock_bh){....}, at: ip_finish_output2+0x243/0x2150
[  146.671696][ T1174]  rib#2: ffffffff93925660 (rcu_read_lock_bh){....}, at: __dev_queue_xmit+0x213/0x2940
[  146.673064][ T1174]  rib#3: ffff8880c19ecd58 (&dev->qdisc_running_key#7){+...}, at: ip_finish_output2+0x714/0x2150
[  146.690358][ T1174]  rib#4: ffff8880c5796898 (&dev->qdisc_xmit_lock_key#3){+.-.}, at: sch_direct_xmit+0x1e2/0x1020
[  146.699875][ T1174]
[  146.699875][ T1174] stack backtrace:
[  146.701091][ T1174] CPU: 0 PID: 1174 Comm: ping Not tainted 5.6.0-rc1+ torvalds#447
[  146.705215][ T1174] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[  146.706565][ T1174] Call Trace:
[  146.707102][ T1174]  dump_stack+0x96/0xdb
[  146.708007][ T1174]  rmnet_get_port.part.9+0x76/0x80 [rmnet]
[  146.709233][ T1174]  rmnet_egress_handler+0x107/0x420 [rmnet]
[  146.710492][ T1174]  ? sch_direct_xmit+0x1e2/0x1020
[  146.716193][ T1174]  rmnet_vnd_start_xmit+0x3d/0xa0 [rmnet]
[  146.717012][ T1174]  dev_hard_start_xmit+0x160/0x740
[  146.717854][ T1174]  sch_direct_xmit+0x265/0x1020
[  146.718577][ T1174]  ? register_lock_class+0x14d0/0x14d0
[  146.719429][ T1174]  ? dev_watchdog+0xac0/0xac0
[  146.723738][ T1174]  ? __dev_queue_xmit+0x15fd/0x2940
[  146.724469][ T1174]  ? lock_acquire+0x164/0x3b0
[  146.725172][ T1174]  __dev_queue_xmit+0x20c7/0x2940
[ ... ]

Fixes: ceed73a ("drivers: net: ethernet: qualcomm: rmnet: Initial implementation")
Signed-off-by: Taehee Yoo <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
djdeath pushed a commit to djdeath/linux that referenced this issue Mar 17, 2020
journal_head::b_transaction and journal_head::b_next_transaction could
be accessed concurrently as noticed by KCSAN,

 LTP: starting fsync04
 /dev/zero: Can't open blockdev
 EXT4-fs (loop0): mounting ext3 file system using the ext4 subsystem
 EXT4-fs (loop0): mounted filesystem with ordered data mode. Opts: (null)
 ==================================================================
 BUG: KCSAN: data-race in __jbd2_journal_refile_buffer [jbd2] / jbd2_write_access_granted [jbd2]

 write to 0xffff99f9b1bd0e30 of 8 bytes by task 25721 on cpu 70:
  __jbd2_journal_refile_buffer+0xdd/0x210 [jbd2]
  __jbd2_journal_refile_buffer at fs/jbd2/transaction.c:2569
  jbd2_journal_commit_transaction+0x2d15/0x3f20 [jbd2]
  (inlined by) jbd2_journal_commit_transaction at fs/jbd2/commit.c:1034
  kjournald2+0x13b/0x450 [jbd2]
  kthread+0x1cd/0x1f0
  ret_from_fork+0x27/0x50

 read to 0xffff99f9b1bd0e30 of 8 bytes by task 25724 on cpu 68:
  jbd2_write_access_granted+0x1b2/0x250 [jbd2]
  jbd2_write_access_granted at fs/jbd2/transaction.c:1155
  jbd2_journal_get_write_access+0x2c/0x60 [jbd2]
  __ext4_journal_get_write_access+0x50/0x90 [ext4]
  ext4_mb_mark_diskspace_used+0x158/0x620 [ext4]
  ext4_mb_new_blocks+0x54f/0xca0 [ext4]
  ext4_ind_map_blocks+0xc79/0x1b40 [ext4]
  ext4_map_blocks+0x3b4/0x950 [ext4]
  _ext4_get_block+0xfc/0x270 [ext4]
  ext4_get_block+0x3b/0x50 [ext4]
  __block_write_begin_int+0x22e/0xae0
  __block_write_begin+0x39/0x50
  ext4_write_begin+0x388/0xb50 [ext4]
  generic_perform_write+0x15d/0x290
  ext4_buffered_write_iter+0x11f/0x210 [ext4]
  ext4_file_write_iter+0xce/0x9e0 [ext4]
  new_sync_write+0x29c/0x3b0
  __vfs_write+0x92/0xa0
  vfs_write+0x103/0x260
  ksys_write+0x9d/0x130
  __x64_sys_write+0x4c/0x60
  do_syscall_64+0x91/0xb05
  entry_SYSCALL_64_after_hwframe+0x49/0xbe

 5 locks held by fsync04/25724:
  #0: ffff99f9911093f8 (sb_writers#13){.+.+}, at: vfs_write+0x21c/0x260
  rib#1: ffff99f9db4c0348 (&sb->s_type->i_mutex_key#15){+.+.}, at: ext4_buffered_write_iter+0x65/0x210 [ext4]
  rib#2: ffff99f5e7dfcf58 (jbd2_handle){++++}, at: start_this_handle+0x1c1/0x9d0 [jbd2]
  rib#3: ffff99f9db4c0168 (&ei->i_data_sem){++++}, at: ext4_map_blocks+0x176/0x950 [ext4]
  rib#4: ffffffff99086b40 (rcu_read_lock){....}, at: jbd2_write_access_granted+0x4e/0x250 [jbd2]
 irq event stamp: 1407125
 hardirqs last  enabled at (1407125): [<ffffffff980da9b7>] __find_get_block+0x107/0x790
 hardirqs last disabled at (1407124): [<ffffffff980da8f9>] __find_get_block+0x49/0x790
 softirqs last  enabled at (1405528): [<ffffffff98a0034c>] __do_softirq+0x34c/0x57c
 softirqs last disabled at (1405521): [<ffffffff97cc67a2>] irq_exit+0xa2/0xc0

 Reported by Kernel Concurrency Sanitizer on:
 CPU: 68 PID: 25724 Comm: fsync04 Tainted: G L 5.6.0-rc2-next-20200221+ rib#7
 Hardware name: HPE ProLiant DL385 Gen10/ProLiant DL385 Gen10, BIOS A40 07/10/2019

The plain reads are outside of jh->b_state_lock critical section which result
in data races. Fix them by adding pairs of READ|WRITE_ONCE().

Reviewed-by: Jan Kara <[email protected]>
Signed-off-by: Qian Cai <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Theodore Ts'o <[email protected]>
djdeath pushed a commit to djdeath/linux that referenced this issue Mar 17, 2020
If scatter-gather operation is allowed, a large USB request is split
into multiple TRBs. For preparing TRBs for sg list, driver iterates
over the list and creates TRB for each sg and mark the chain bit to
false for the last sg. The current IOMMU driver is clubbing the list
of sgs which shares a page boundary into one and giving it to USB driver.
With this the number of sgs mapped it not equal to the the number of sgs
passed. Because of this USB driver is not marking the chain bit to false
since it couldn't iterate to the last sg. This patch addresses this issue
by marking the chain bit to false if it is the last mapped sg.

At a practical level, this patch resolves USB transfer stalls
seen with adb on dwc3 based db845c, pixel3 and other qcom
hardware after functionfs gadget added scatter-gather support
around v4.20.

Credit also to Anurag Kumar Vulisha <[email protected]>
who implemented a very similar fix to this issue.

Cc: Felipe Balbi <[email protected]>
Cc: Yang Fei <[email protected]>
Cc: Thinh Nguyen <[email protected]>
Cc: Tejas Joglekar <[email protected]>
Cc: Andrzej Pietrasiewicz <[email protected]>
Cc: Jack Pham <[email protected]>
Cc: Todd Kjos <[email protected]>
Cc: Greg KH <[email protected]>
Cc: Linux USB List <[email protected]>
Cc: stable <[email protected]> rib#4.20+
Signed-off-by: Pratham Pratap <[email protected]>
[jstultz: Slight tweak to remove sg_is_last() usage, reworked
          commit message, minor comment tweak]
Signed-off-by: John Stultz <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
djdeath pushed a commit to djdeath/linux that referenced this issue Mar 17, 2020
<4>[  259.166718] WARNING: inconsistent lock state
<4>[  259.166725] 5.6.0-rc3-CI-CI_DRM_8038+ rib#1 Tainted: G     U
<4>[  259.166727] --------------------------------
<4>[  259.166731] inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage.
<4>[  259.166741] rtcwake/4221 [HC0[0]:SC0[0]:HE1:SE1] takes:
<4>[  259.166745] ffffffff82635198 (rtc_lock){?...}, at: cmos_interrupt+0x18/0x100
<4>[  259.166768] {IN-HARDIRQ-W} state was registered at:
<4>[  259.166780]   lock_acquire+0xa7/0x1c0
<4>[  259.166790]   _raw_spin_lock+0x2a/0x40
<4>[  259.166799]   cmos_interrupt+0x18/0x100
<4>[  259.166808]   rtc_handler+0x75/0xc0
<4>[  259.166822]   acpi_ev_fixed_event_detect+0xf9/0x132
<4>[  259.166829]   acpi_ev_sci_xrupt_handler+0xb/0x28
<4>[  259.166838]   acpi_irq+0x13/0x30
<4>[  259.166849]   __handle_irq_event_percpu+0x41/0x2c0
<4>[  259.166859]   handle_irq_event_percpu+0x2b/0x70
<4>[  259.166868]   handle_irq_event+0x2f/0x50
<4>[  259.166875]   handle_fasteoi_irq+0x8e/0x150
<4>[  259.166883]   do_IRQ+0x7e/0x160
<4>[  259.166891]   ret_from_intr+0x0/0x35
<4>[  259.166898]   mwait_idle+0x7e/0x200
<4>[  259.166905]   do_idle+0x1bb/0x260
<4>[  259.166912]   cpu_startup_entry+0x14/0x20
<4>[  259.166921]   start_secondary+0x15f/0x1b0
<4>[  259.166929]   secondary_startup_64+0xa4/0xb0
<4>[  259.167264] irq event stamp: 41593
<4>[  259.167275] hardirqs last  enabled at (41593): [<ffffffff81a394e7>] _raw_spin_unlock_irqrestore+0x47/0x60
<4>[  259.167285] hardirqs last disabled at (41592): [<ffffffff81a3926d>] _raw_spin_lock_irqsave+0xd/0x50
<4>[  259.167296] softirqs last  enabled at (41568): [<ffffffff81e00385>] __do_softirq+0x385/0x47f
<4>[  259.167306] softirqs last disabled at (41561): [<ffffffff810babaa>] irq_exit+0xba/0xc0
<4>[  259.167309]
                  other info that might help us debug this:
<4>[  259.167312]  Possible unsafe locking scenario:

<4>[  259.167314]        CPU0
<4>[  259.167316]        ----
<4>[  259.167319]   lock(rtc_lock);
<4>[  259.167324]   <Interrupt>
<4>[  259.167326]     lock(rtc_lock);
<4>[  259.167332]
                   *** DEADLOCK ***

<4>[  259.167337] 6 locks held by rtcwake/4221:
<4>[  259.167665]  #0: ffff888175e89408 (sb_writers#5){.+.+}, at: vfs_write+0x1a4/0x1d0
<4>[  259.167687]  rib#1: ffff88816e112080 (&of->mutex){+.+.}, at: kernfs_fop_write+0xdd/0x1b0
<4>[  259.167706]  rib#2: ffff888179be85e0 (kn->count#236){.+.+}, at: kernfs_fop_write+0xe6/0x1b0
<4>[  259.167728]  rib#3: ffffffff82641e00 (system_transition_mutex){+.+.}, at: pm_suspend+0xb3/0x3b0
<4>[  259.167748]  rib#4: ffffffff826b3ea0 (acpi_scan_lock){+.+.}, at: acpi_suspend_begin+0x47/0x80
<4>[  259.167763]  rib#5: ffff888178f6b960 (&dev->mutex){....}, at: device_resume+0x92/0x1c0
<4>[  259.167778]
                  stack backtrace:
<4>[  259.167788] CPU: 1 PID: 4221 Comm: rtcwake Tainted: G     U            5.6.0-rc3-CI-CI_DRM_8038+ rib#1
<4>[  259.168106] Hardware name: Google Soraka/Soraka, BIOS MrChromebox-4.10 08/25/2019
<4>[  259.168110] Call Trace:
<4>[  259.168123]  dump_stack+0x71/0x9b
<4>[  259.168133]  mark_lock+0x49a/0x500
<4>[  259.168457]  ? print_shortest_lock_dependencies+0x200/0x200
<4>[  259.168469]  __lock_acquire+0x6d4/0x15d0
<4>[  259.168479]  ? __lock_acquire+0x460/0x15d0
<4>[  259.168490]  lock_acquire+0xa7/0x1c0
<4>[  259.168500]  ? cmos_interrupt+0x18/0x100
<4>[  259.168824]  _raw_spin_lock+0x2a/0x40
<4>[  259.168834]  ? cmos_interrupt+0x18/0x100
<4>[  259.168843]  cmos_interrupt+0x18/0x100
<4>[  259.169159]  cmos_resume+0x1fd/0x290
<4>[  259.169174]  ? __acpi_pm_set_device_wakeup+0x24/0x100
<4>[  259.169498]  pnp_bus_resume+0x5e/0x90
<4>[  259.169509]  ? pnp_bus_suspend+0x10/0x10
<4>[  259.169518]  dpm_run_callback+0x64/0x280
<4>[  259.169530]  device_resume+0xd4/0x1c0
<4>[  259.169540]  ? dpm_watchdog_set+0x60/0x60
<4>[  259.169860]  dpm_resume+0x106/0x410
<4>[  259.169870]  ? dpm_resume_early+0x38c/0x3e0
<4>[  259.169881]  dpm_resume_end+0x8/0x10
<4>[  259.170195]  suspend_devices_and_enter+0x16f/0xbe0
<4>[  259.170211]  ? rcu_read_lock_sched_held+0x4d/0x80
<4>[  259.170528]  pm_suspend+0x344/0x3b0
<4>[  259.170542]  state_store+0x78/0xe0
<4>[  259.170559]  kernfs_fop_write+0x112/0x1b0
<4>[  259.170579]  vfs_write+0xb9/0x1d0
<4>[  259.170896]  ksys_write+0x9f/0xe0
<4>[  259.170907]  do_syscall_64+0x4f/0x220
<4>[  259.170918]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
<4>[  259.171229] RIP: 0033:0x7f9b4f3cb154
<4>[  259.171240] Code: 89 02 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 8d 05 b1 07 2e 00 8b 00 85 c0 75 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 f3 c3 66 90 41 54 55 49 89 d4 53 48 89 f5
<4>[  259.171245] RSP: 002b:00007ffc057ce438 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
<4>[  259.171253] RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007f9b4f3cb154
<4>[  259.171257] RDX: 0000000000000004 RSI: 000055f4b3d185a0 RDI: 000000000000000a
<4>[  259.171572] RBP: 000055f4b3d185a0 R08: 000055f4b3d165e0 R09: 00007f9b4fab7740
<4>[  259.171576] R10: 000055f4b3d14010 R11: 0000000000000246 R12: 000055f4b3d16500
<4>[  259.171580] R13: 0000000000000004 R14: 00007f9b4f6a32a0 R15: 00007f9b4f6a2760

Fixes: c6d3a27 ("rtc: cmos: acknowledge ACPI driven wake alarms upon resume")
Fixes: 311ee9c ("rtc: cmos: allow using ACPI for RTC alarm instead of HPET")
Signed-off-by: Chris Wilson <[email protected]>
Cc: Zhang Rui <[email protected]>
Cc: Alexandre Belloni <[email protected]>
Cc: Alessandro Zummo <[email protected]>
Cc: [email protected]
Cc: <[email protected]> # v4.18+
Signed-off-by: Jani Nikula <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Jun 17, 2021
We inadvertently create a dependency on mmap_sem with a whole chain.

This breaks any user who wants to take a lock and call rcu_barrier(),
while also taking that lock inside mmap_sem:

<4> [604.892532] ======================================================
<4> [604.892534] WARNING: possible circular locking dependency detected
<4> [604.892536] 5.6.0-rc7-CI-Patchwork_17096+ rib#1 Tainted: G     U
<4> [604.892537] ------------------------------------------------------
<4> [604.892538] kms_frontbuffer/2595 is trying to acquire lock:
<4> [604.892540] ffffffff8264a558 (rcu_state.barrier_mutex){+.+.}, at: rcu_barrier+0x23/0x190
<4> [604.892547]
but task is already holding lock:
<4> [604.892547] ffff888484716050 (reservation_ww_class_mutex){+.+.}, at: i915_gem_object_pin_to_display_plane+0x89/0x270 [i915]
<4> [604.892592]
which lock already depends on the new lock.
<4> [604.892593]
the existing dependency chain (in reverse order) is:
<4> [604.892594]
-> rib#6 (reservation_ww_class_mutex){+.+.}:
<4> [604.892597]        __ww_mutex_lock.constprop.15+0xc3/0x1090
<4> [604.892598]        ww_mutex_lock+0x39/0x70
<4> [604.892600]        dma_resv_lockdep+0x10e/0x1f5
<4> [604.892602]        do_one_initcall+0x58/0x300
<4> [604.892604]        kernel_init_freeable+0x17b/0x1dc
<4> [604.892605]        kernel_init+0x5/0x100
<4> [604.892606]        ret_from_fork+0x24/0x50
<4> [604.892607]
-> rib#5 (reservation_ww_class_acquire){+.+.}:
<4> [604.892609]        dma_resv_lockdep+0xec/0x1f5
<4> [604.892610]        do_one_initcall+0x58/0x300
<4> [604.892610]        kernel_init_freeable+0x17b/0x1dc
<4> [604.892611]        kernel_init+0x5/0x100
<4> [604.892612]        ret_from_fork+0x24/0x50
<4> [604.892613]
-> rib#4 (&mm->mmap_sem#2){++++}:
<4> [604.892615]        __might_fault+0x63/0x90
<4> [604.892617]        _copy_to_user+0x1e/0x80
<4> [604.892619]        perf_read+0x200/0x2b0
<4> [604.892621]        vfs_read+0x96/0x160
<4> [604.892622]        ksys_read+0x9f/0xe0
<4> [604.892623]        do_syscall_64+0x4f/0x220
<4> [604.892624]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
<4> [604.892625]
-> rib#3 (&cpuctx_mutex){+.+.}:
<4> [604.892626]        __mutex_lock+0x9a/0x9c0
<4> [604.892627]        perf_event_init_cpu+0xa4/0x140
<4> [604.892629]        perf_event_init+0x19d/0x1cd
<4> [604.892630]        start_kernel+0x362/0x4e4
<4> [604.892631]        secondary_startup_64+0xa4/0xb0
<4> [604.892631]
-> rib#2 (pmus_lock){+.+.}:
<4> [604.892633]        __mutex_lock+0x9a/0x9c0
<4> [604.892633]        perf_event_init_cpu+0x6b/0x140
<4> [604.892635]        cpuhp_invoke_callback+0x9b/0x9d0
<4> [604.892636]        _cpu_up+0xa2/0x140
<4> [604.892637]        do_cpu_up+0x61/0xa0
<4> [604.892639]        smp_init+0x57/0x96
<4> [604.892639]        kernel_init_freeable+0x87/0x1dc
<4> [604.892640]        kernel_init+0x5/0x100
<4> [604.892642]        ret_from_fork+0x24/0x50
<4> [604.892642]
-> rib#1 (cpu_hotplug_lock.rw_sem){++++}:
<4> [604.892643]        cpus_read_lock+0x34/0xd0
<4> [604.892644]        rcu_barrier+0xaa/0x190
<4> [604.892645]        kernel_init+0x21/0x100
<4> [604.892647]        ret_from_fork+0x24/0x50
<4> [604.892647]
-> #0 (rcu_state.barrier_mutex){+.+.}:
<4> [604.892649]        __lock_acquire+0x1328/0x15d0
<4> [604.892650]        lock_acquire+0xa7/0x1c0
<4> [604.892651]        __mutex_lock+0x9a/0x9c0
<4> [604.892652]        rcu_barrier+0x23/0x190
<4> [604.892680]        i915_gem_object_unbind+0x29d/0x3f0 [i915]
<4> [604.892707]        i915_gem_object_pin_to_display_plane+0x141/0x270 [i915]
<4> [604.892737]        intel_pin_and_fence_fb_obj+0xec/0x1f0 [i915]
<4> [604.892767]        intel_plane_pin_fb+0x3f/0xd0 [i915]
<4> [604.892797]        intel_prepare_plane_fb+0x13b/0x5c0 [i915]
<4> [604.892798]        drm_atomic_helper_prepare_planes+0x85/0x110
<4> [604.892827]        intel_atomic_commit+0xda/0x390 [i915]
<4> [604.892828]        drm_atomic_helper_set_config+0x57/0xa0
<4> [604.892830]        drm_mode_setcrtc+0x1c4/0x720
<4> [604.892830]        drm_ioctl_kernel+0xb0/0xf0
<4> [604.892831]        drm_ioctl+0x2e1/0x390
<4> [604.892833]        ksys_ioctl+0x7b/0x90
<4> [604.892835]        __x64_sys_ioctl+0x11/0x20
<4> [604.892835]        do_syscall_64+0x4f/0x220
<4> [604.892836]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
<4> [604.892837]

Changes since v1:
- Use (*values)[n++] in perf_read_one().
Changes since v2:
- Centrally allocate values.

Signed-off-by: Maarten Lankhorst <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]
Signed-off-by: Rodrigo Vivi <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue Jun 17, 2021
As previously noted in commit 66e4f4a ("rtc: cmos: Use
spin_lock_irqsave() in cmos_interrupt()"):

<4>[  254.192378] WARNING: inconsistent lock state
<4>[  254.192384] 5.12.0-rc1-CI-CI_DRM_9834+ rib#1 Not tainted
<4>[  254.192396] --------------------------------
<4>[  254.192400] inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage.
<4>[  254.192409] rtcwake/5309 [HC0[0]:SC0[0]:HE1:SE1] takes:
<4>[  254.192429] ffffffff8263c5f8 (rtc_lock){?...}-{2:2}, at: cmos_interrupt+0x18/0x100
<4>[  254.192481] {IN-HARDIRQ-W} state was registered at:
<4>[  254.192488]   lock_acquire+0xd1/0x3d0
<4>[  254.192504]   _raw_spin_lock+0x2a/0x40
<4>[  254.192519]   cmos_interrupt+0x18/0x100
<4>[  254.192536]   rtc_handler+0x1f/0xc0
<4>[  254.192553]   acpi_ev_fixed_event_detect+0x109/0x13c
<4>[  254.192574]   acpi_ev_sci_xrupt_handler+0xb/0x28
<4>[  254.192596]   acpi_irq+0x13/0x30
<4>[  254.192620]   __handle_irq_event_percpu+0x43/0x2c0
<4>[  254.192641]   handle_irq_event_percpu+0x2b/0x70
<4>[  254.192661]   handle_irq_event+0x2f/0x50
<4>[  254.192680]   handle_fasteoi_irq+0x9e/0x150
<4>[  254.192693]   __common_interrupt+0x76/0x140
<4>[  254.192715]   common_interrupt+0x96/0xc0
<4>[  254.192732]   asm_common_interrupt+0x1e/0x40
<4>[  254.192750]   _raw_spin_unlock_irqrestore+0x38/0x60
<4>[  254.192767]   resume_irqs+0xba/0xf0
<4>[  254.192786]   dpm_resume_noirq+0x245/0x3d0
<4>[  254.192811]   suspend_devices_and_enter+0x230/0xaa0
<4>[  254.192835]   pm_suspend.cold.8+0x301/0x34a
<4>[  254.192859]   state_store+0x7b/0xe0
<4>[  254.192879]   kernfs_fop_write_iter+0x11d/0x1c0
<4>[  254.192899]   new_sync_write+0x11d/0x1b0
<4>[  254.192916]   vfs_write+0x265/0x390
<4>[  254.192933]   ksys_write+0x5a/0xd0
<4>[  254.192949]   do_syscall_64+0x33/0x80
<4>[  254.192965]   entry_SYSCALL_64_after_hwframe+0x44/0xae
<4>[  254.192986] irq event stamp: 43775
<4>[  254.192994] hardirqs last  enabled at (43775): [<ffffffff81c00c42>] asm_sysvec_apic_timer_interrupt+0x12/0x20
<4>[  254.193023] hardirqs last disabled at (43774): [<ffffffff81aa691a>] sysvec_apic_timer_interrupt+0xa/0xb0
<4>[  254.193049] softirqs last  enabled at (42548): [<ffffffff81e00342>] __do_softirq+0x342/0x48e
<4>[  254.193074] softirqs last disabled at (42543): [<ffffffff810b45fd>] irq_exit_rcu+0xad/0xd0
<4>[  254.193101]
                  other info that might help us debug this:
<4>[  254.193107]  Possible unsafe locking scenario:

<4>[  254.193112]        CPU0
<4>[  254.193117]        ----
<4>[  254.193121]   lock(rtc_lock);
<4>[  254.193137]   <Interrupt>
<4>[  254.193142]     lock(rtc_lock);
<4>[  254.193156]
                   *** DEADLOCK ***

<4>[  254.193161] 6 locks held by rtcwake/5309:
<4>[  254.193174]  #0: ffff888104861430 (sb_writers#5){.+.+}-{0:0}, at: ksys_write+0x5a/0xd0
<4>[  254.193232]  rib#1: ffff88810f823288 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0xe7/0x1c0
<4>[  254.193282]  rib#2: ffff888100cef3c0 (kn->active#285
<7>[  254.192706] i915 0000:00:02.0: [drm:intel_modeset_setup_hw_state [i915]] [CRTC:51:pipe A] hw state readout: disabled
<4>[  254.193307] ){.+.+}-{0:0}, at: kernfs_fop_write_iter+0xf0/0x1c0
<4>[  254.193333]  rib#3: ffffffff82649fa8 (system_transition_mutex){+.+.}-{3:3}, at: pm_suspend.cold.8+0xce/0x34a
<4>[  254.193387]  rib#4: ffffffff827a2108 (acpi_scan_lock){+.+.}-{3:3}, at: acpi_suspend_begin+0x47/0x70
<4>[  254.193433]  rib#5: ffff8881019ea178 (&dev->mutex){....}-{3:3}, at: device_resume+0x68/0x1e0
<4>[  254.193485]
                  stack backtrace:
<4>[  254.193492] CPU: 1 PID: 5309 Comm: rtcwake Not tainted 5.12.0-rc1-CI-CI_DRM_9834+ rib#1
<4>[  254.193514] Hardware name: Google Soraka/Soraka, BIOS MrChromebox-4.10 08/25/2019
<4>[  254.193524] Call Trace:
<4>[  254.193536]  dump_stack+0x7f/0xad
<4>[  254.193567]  mark_lock.part.47+0x8ca/0xce0
<4>[  254.193604]  __lock_acquire+0x39b/0x2590
<4>[  254.193626]  ? asm_sysvec_apic_timer_interrupt+0x12/0x20
<4>[  254.193660]  lock_acquire+0xd1/0x3d0
<4>[  254.193677]  ? cmos_interrupt+0x18/0x100
<4>[  254.193716]  _raw_spin_lock+0x2a/0x40
<4>[  254.193735]  ? cmos_interrupt+0x18/0x100
<4>[  254.193758]  cmos_interrupt+0x18/0x100
<4>[  254.193785]  cmos_resume+0x2ac/0x2d0
<4>[  254.193813]  ? acpi_pm_set_device_wakeup+0x1f/0x110
<4>[  254.193842]  ? pnp_bus_suspend+0x10/0x10
<4>[  254.193864]  pnp_bus_resume+0x5e/0x90
<4>[  254.193885]  dpm_run_callback+0x5f/0x240
<4>[  254.193914]  device_resume+0xb2/0x1e0
<4>[  254.193942]  ? pm_dev_err+0x25/0x25
<4>[  254.193974]  dpm_resume+0xea/0x3f0
<4>[  254.194005]  dpm_resume_end+0x8/0x10
<4>[  254.194030]  suspend_devices_and_enter+0x29b/0xaa0
<4>[  254.194066]  pm_suspend.cold.8+0x301/0x34a
<4>[  254.194094]  state_store+0x7b/0xe0
<4>[  254.194124]  kernfs_fop_write_iter+0x11d/0x1c0
<4>[  254.194151]  new_sync_write+0x11d/0x1b0
<4>[  254.194183]  vfs_write+0x265/0x390
<4>[  254.194207]  ksys_write+0x5a/0xd0
<4>[  254.194232]  do_syscall_64+0x33/0x80
<4>[  254.194251]  entry_SYSCALL_64_after_hwframe+0x44/0xae
<4>[  254.194274] RIP: 0033:0x7f07d79691e7
<4>[  254.194293] Code: 64 89 02 48 c7 c0 ff ff ff ff eb bb 0f 1f 80 00 00 00 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24
<4>[  254.194312] RSP: 002b:00007ffd9cc2c768 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
<4>[  254.194337] RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007f07d79691e7
<4>[  254.194352] RDX: 0000000000000004 RSI: 0000556ebfc63590 RDI: 000000000000000b
<4>[  254.194366] RBP: 0000556ebfc63590 R08: 0000000000000000 R09: 0000000000000004
<4>[  254.194379] R10: 0000556ebf0ec2a6 R11: 0000000000000246 R12: 0000000000000004

which breaks S3-resume on fi-kbl-soraka presumably as that's slow enough
to trigger the alarm during the suspend.

Fixes: 6950d04 ("rtc: cmos: Replace spin_lock_irqsave with spin_lock in hard IRQ")
References: 66e4f4a ("rtc: cmos: Use spin_lock_irqsave() in cmos_interrupt()"):
Signed-off-by: Chris Wilson <[email protected]>
Cc: Xiaofei Tan <[email protected]>
Cc: Alexandre Belloni <[email protected]>
Cc: Alessandro Zummo <[email protected]>
Cc: Ville Syrjälä <[email protected]>
Signed-off-by: Rodrigo Vivi <[email protected]>
matt-auld pushed a commit to matt-auld/linux that referenced this issue May 24, 2022
As reported by Alan, the CFI (Call Frame Information) in the VDSO time
routines is incorrect since commit ce7d805 ("powerpc/vdso: Prepare
for switching VDSO to generic C implementation.").

DWARF has a concept called the CFA (Canonical Frame Address), which on
powerpc is calculated as an offset from the stack pointer (r1). That
means when the stack pointer is changed there must be a corresponding
CFI directive to update the calculation of the CFA.

The current code is missing those directives for the changes to r1,
which prevents gdb from being able to generate a backtrace from inside
VDSO functions, eg:

  Breakpoint 1, 0x00007ffff7f804dc in __kernel_clock_gettime ()
  (gdb) bt
  #0  0x00007ffff7f804dc in __kernel_clock_gettime ()
  rib#1  0x00007ffff7d8872c in clock_gettime@@GLIBC_2.17 () from /lib64/libc.so.6
  rib#2  0x00007fffffffd960 in ?? ()
  rib#3  0x00007ffff7d8872c in clock_gettime@@GLIBC_2.17 () from /lib64/libc.so.6
  Backtrace stopped: frame did not save the PC

Alan helpfully describes some rules for correctly maintaining the CFI information:

  1) Every adjustment to the current frame address reg (ie. r1) must be
     described, and exactly at the instruction where r1 changes. Why?
     Because stack unwinding might want to access previous frames.

  2) If a function changes LR or any non-volatile register, the save
     location for those regs must be given. The CFI can be at any
     instruction after the saves up to the point that the reg is
     changed.
     (Exception: LR save should be described before a bl. not after)

  3) If asychronous unwind info is needed then restores of LR and
     non-volatile regs must also be described. The CFI can be at any
     instruction after the reg is restored up to the point where the
     save location is (potentially) trashed.

Fix the inability to backtrace by adding CFI directives describing the
changes to r1, ie. satisfying rule 1.

Also change the information for LR to point to the copy saved on the
stack, not the value in r0 that will be overwritten by the function
call.

Finally, add CFI directives describing the save/restore of r2.

With the fix gdb can correctly back trace and navigate up and down the stack:

  Breakpoint 1, 0x00007ffff7f804dc in __kernel_clock_gettime ()
  (gdb) bt
  #0  0x00007ffff7f804dc in __kernel_clock_gettime ()
  rib#1  0x00007ffff7d8872c in clock_gettime@@GLIBC_2.17 () from /lib64/libc.so.6
  rib#2  0x0000000100015b60 in gettime ()
  rib#3  0x000000010000c8bc in print_long_format ()
  rib#4  0x000000010000d180 in print_current_files ()
  rib#5  0x00000001000054ac in main ()
  (gdb) up
  rib#1  0x00007ffff7d8872c in clock_gettime@@GLIBC_2.17 () from /lib64/libc.so.6
  (gdb)
  rib#2  0x0000000100015b60 in gettime ()
  (gdb)
  rib#3  0x000000010000c8bc in print_long_format ()
  (gdb)
  rib#4  0x000000010000d180 in print_current_files ()
  (gdb)
  rib#5  0x00000001000054ac in main ()
  (gdb)
  Initial frame selected; you cannot go up.
  (gdb) down
  rib#4  0x000000010000d180 in print_current_files ()
  (gdb)
  rib#3  0x000000010000c8bc in print_long_format ()
  (gdb)
  rib#2  0x0000000100015b60 in gettime ()
  (gdb)
  rib#1  0x00007ffff7d8872c in clock_gettime@@GLIBC_2.17 () from /lib64/libc.so.6
  (gdb)
  #0  0x00007ffff7f804dc in __kernel_clock_gettime ()
  (gdb)

Fixes: ce7d805 ("powerpc/vdso: Prepare for switching VDSO to generic C implementation.")
Cc: [email protected] # v5.11+
Reported-by: Alan Modra <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Reviewed-by: Segher Boessenkool <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
matt-auld pushed a commit to matt-auld/linux that referenced this issue May 24, 2022
Do not allow to write timestamps on RX rings if PF is being configured.
When PF is being configured RX rings can be freed or rebuilt. If at the
same time timestamps are updated, the kernel will crash by dereferencing
null RX ring pointer.

PID: 1449   TASK: ff187d28ed658040  CPU: 34  COMMAND: "ice-ptp-0000:51"
 #0 [ff1966a94a713bb0] machine_kexec at ffffffff9d05a0be
 rib#1 [ff1966a94a713c08] __crash_kexec at ffffffff9d192e9d
 rib#2 [ff1966a94a713cd0] crash_kexec at ffffffff9d1941bd
 rib#3 [ff1966a94a713ce8] oops_end at ffffffff9d01bd54
 rib#4 [ff1966a94a713d08] no_context at ffffffff9d06bda4
 rib#5 [ff1966a94a713d60] __bad_area_nosemaphore at ffffffff9d06c10c
 rib#6 [ff1966a94a713da8] do_page_fault at ffffffff9d06cae4
 rib#7 [ff1966a94a713de0] page_fault at ffffffff9da0107e
    [exception RIP: ice_ptp_update_cached_phctime+91]
    RIP: ffffffffc076db8b  RSP: ff1966a94a713e98  RFLAGS: 00010246
    RAX: 16e3db9c6b7ccae4  RBX: ff187d269dd3c180  RCX: ff187d269cd4d018
    RDX: 0000000000000000  RSI: 0000000000000000  RDI: 0000000000000000
    RBP: ff187d269cfcc644   R8: ff187d339b9641b0   R9: 0000000000000000
    R10: 0000000000000002  R11: 0000000000000000  R12: ff187d269cfcc648
    R13: ffffffff9f128784  R14: ffffffff9d101b70  R15: ff187d269cfcc640
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 rib#8 [ff1966a94a713ea0] ice_ptp_periodic_work at ffffffffc076dbef [ice]
 rib#9 [ff1966a94a713ee0] kthread_worker_fn at ffffffff9d101c1b
 rib#10 [ff1966a94a713f10] kthread at ffffffff9d101b4d
 rib#11 [ff1966a94a713f50] ret_from_fork at ffffffff9da0023f

Fixes: 77a7811 ("ice: enable receive hardware timestamping")
Signed-off-by: Arkadiusz Kubalewski <[email protected]>
Reviewed-by: Michal Schmidt <[email protected]>
Tested-by: Dave Cain <[email protected]>
Tested-by: Gurucharan <[email protected]> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <[email protected]>
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