Re: [rfcomm_run] WARNING: CPU: 0 PID: 95 at kernel/sched/core.c:7312 __might_sleep()

[Richard Guy Briggs <rgb@redhat.com>]

On 14/10/27, Fengguang Wu wrote:
> On Mon, Oct 27, 2014 at 02:36:27PM +0100, Peter Zijlstra wrote:
> > On Mon, Oct 27, 2014 at 09:06:21PM +0800, Fengguang Wu wrote:
> > > Hi Peter,
> > > 
> > > FYI, this bug seems still there on v3.18-rc2.
> > 
> > Oh, right, I commented out that patch and the audit one because I was
> > waiting for some feedback. Lemme go prod people.
> 
> audit? I do hit an kauditd_thread warning recently:
> 
> [   89.102903] ------------[ cut here ]------------
> [   89.107650] WARNING: CPU: 6 PID: 3175 at /kbuild/src/lkp/kernel/sched/core.c:7310 __might_sleep+0x8e/0xc0()
> [   89.117606] do not call blocking ops when !TASK_RUNNING; state=1 set at [<ffffffff811088f8>] kauditd_thread+0x168/0x220
> [   89.128588] Modules linked in: btrfs raid456 async_raid6_recov async_memcpy async_pq async_xor xor async_tx raid6_pq ipmi_watchdog ipmi_msghandler ses enclosure sg s
> d_mod ata_generic pata_acpi floppy parport_pc parport snd_pcm snd_timer snd ata_piix soundcore i2c_i801 serio_raw mptsas libata pcspkr i5400_edac shpchp mptscsih edac_core mptbase i5k_amb tpm_infineon scsi_transport_sas                                                                                                                     [   89.165503] CPU: 6 PID: 3175 Comm: kauditd Tainted: G        W      3.18.0-rc2-g8696cce #1
> [   89.173988] Hardware name: Supermicro X7DW3/X7DWN, BIOS 6.00 09/28/2007
> [   89.180735]  0000000000000009 ffff880229d8bd78 ffffffff81876101 ffff88022fd90478
> [   89.188596]  ffff880229d8bdc8 ffff880229d8bdb8 ffffffff8106a421 ffff880229d8bda8
> [   89.196483]  ffffffff81b345f0 0000000000000038 0000000000000000 ffff8800bd0fd850
> [   89.204364] Call Trace:
> [   89.206945]  [<ffffffff81876101>] dump_stack+0x4e/0x68
> [   89.212209]  [<ffffffff8106a421>] warn_slowpath_common+0x81/0xa0
> [   89.218362]  [<ffffffff8106a486>] warn_slowpath_fmt+0x46/0x50
> [   89.224257]  [<ffffffff811088f8>] ? kauditd_thread+0x168/0x220
> [   89.230216]  [<ffffffff811088f8>] ? kauditd_thread+0x168/0x220
> [   89.236201]  [<ffffffff8109039e>] __might_sleep+0x8e/0xc0
> [   89.241746]  [<ffffffff8110897b>] kauditd_thread+0x1eb/0x220
> [   89.247536]  [<ffffffff81098030>] ? wake_up_state+0x20/0x20
> [   89.253247]  [<ffffffff81108790>] ? audit_printk_skb+0x70/0x70
> [   89.259237]  [<ffffffff81089e8f>] kthread+0xef/0x110
> [   89.264330]  [<ffffffff81089da0>] ? kthread_create_on_node+0x180/0x180
> [   89.271010]  [<ffffffff8187eabc>] ret_from_fork+0x7c/0xb0
> [   89.276543]  [<ffffffff81089da0>] ? kthread_create_on_node+0x180/0x180
> [   89.283205] ---[ end trace 4692477bd4539c42 ]---
> 
> However I'm not sure if it's a bug in 3.18-rc2, or one of the
> following trees introduced that warning.

My guess is that none of the trees below would likely have caused this
except maybe top/locking/urgent (and obviously the peterz-queue ones),
and even then, I'd look in the v3.18-rc2 code first.  I'll have a look
in the audit code to see if anything jumps out at me.  There have been
wait issues in audit recently and may not be entirely cleaned up.

>  amirv/driver_updates
>  arm-platforms/irq/irqchip_state
>  arm-platforms/irq/priority_drop
>  asoc/for-linus
>  asoc/for-next
>  asoc/topic/sgtl5000
>  bluetooth/master
>  chanwoo-extcon/extcon-next
>  drm-intel/drm-intel-next-queued
>  drm-intel/drm-intel-nightly
>  hwmon/poweroff-handler
>  ipsec-next/master
>  ipsec-next/testing
>  jiangliu/ioapic/hotplug_v7
>  kees/lsm/modpin.old
>  kvm/queue
>  m68k/for-3.19
>  m68k/for-linus
>  m68k/for-next
>  m68k/m68k-queue
>  mips-john/mips-for-linux-next
>  net/master
>  net-next/master
>  peterz-queue/locking/urgent
>  peterz-queue/perf/core
>  peterz-queue/perf/urgent
>  peterz-queue/sched/urgent
>  peterz-queue/sched/wait
>  peterz-queue/timers/urgent
>  regulator/for-next
>  renesas/cleanup-for-v3.19
>  renesas/devel
>  renesas/dt-clocksource-for-v3.19
>  renesas/dt-du-for-v3.19
>  renesas/dt-for-v3.19
>  renesas/next
>  renesas/soc-for-v3.19
>  sound/for-linus
>  spi/for-linus
>  spi/for-next
>  staging/staging-testing
>  tip/locking/urgent
>  usb/usb-linus
> 
> Thanks,
> Fengguang

- RGB

--
Richard Guy Briggs <rbriggs@redhat.com>
Senior Software Engineer, Kernel Security, AMER ENG Base Operating Systems, Red Hat
Remote, Ottawa, Canada
Voice: +1.647.777.2635, Internal: (81) 32635, Alt: +1.613.693.0684x3545