Bug 12574
| Summary: | possible circular locking dependency detected | ||
|---|---|---|---|
| Product: | Power Management | Reporter: | Michael S. Tsirkin (m.s.tsirkin) |
| Component: | Hibernation/Suspend | Assignee: | power-management_other |
| Status: | CLOSED INSUFFICIENT_DATA | ||
| Severity: | normal | CC: | rjw |
| Priority: | P1 | ||
| Hardware: | All | ||
| OS: | Linux | ||
| Kernel Version: | 2.6.29-rc3 | Subsystem: | |
| Regression: | Yes | Bisected commit-id: | |
| Bug Depends on: | |||
| Bug Blocks: | 7216, 12398 | ||
| Attachments: |
full dmesg output including the warning
kernel 2.6.29-rc3 .config with lockdep enabled |
||
Created attachment 20040 [details]
full dmesg output including the warning
Created attachment 20041 [details]
kernel 2.6.29-rc3 .config with lockdep enabled
References : http://lkml.org/lkml/2009/2/9/205 On Sunday 15 February 2009, Michael S. Tsirkin wrote:
> It's still there in -rc5.
>
> On Sat, Feb 14, 2009 at 10:38 PM, Rafael J. Wysocki <rjw@sisk.pl> wrote:
> > This message has been generated automatically as a part of a report
> > of recent regressions.
> >
> > The following bug entry is on the current list of known regressions
> > from 2.6.28. Please verify if it still should be listed and let me know
> > (either way).
> >
> >
> > Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=12574
> > Subject : possible circular locking dependency detected
> > Submitter : Michael S. Tsirkin <m.s.tsirkin@gmail.com>
> > Date : 2009-01-29 11:35 (17 days old)
> > References : http://lkml.org/lkml/2009/2/9/205
On Tuesday 03 March 2009, Michael S. Tsirkin wrote:
> On Tue, Mar 3, 2009 at 9:25 PM, Rafael J. Wysocki <rjw@sisk.pl> wrote:
> > This message has been generated automatically as a part of a report
> > of recent regressions.
> >
> > The following bug entry is on the current list of known regressions
> > from 2.6.28. Please verify if it still should be listed and let me know
> > (either way).
> >
> >
> > Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=12574
> > Subject : possible circular locking dependency detected
> > Submitter : Michael S. Tsirkin <m.s.tsirkin@gmail.com>
> > Date : 2009-01-29 11:35 (34 days old)
> > References : http://lkml.org/lkml/2009/2/9/205
> >
> >
> >
>
> I don't seem to observe this warning in v2.6.29-rc6 anymore.
I see this again in 2.6.29-rc7. Reopening. as the problem exists in 2.6.29-rc3 while it doesn't in 2.6.28 could you please use git-bisect to see which commit introduces this bug? >
> as the problem exists in 2.6.29-rc3 while it doesn't in 2.6.28
> could you please use git-bisect to see which commit introduces this bug?
>
Is this really necessary? I am not sure I can get my hands on this machine.
It seems pretty clear where the circular dependency is -
the real question is IMO what the right fix is.
<div dir="ltr"><div class="gmail_quote"><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">as the problem exists in 2.6.29-rc3 while it doesn't in 2.6.28<br>
could you please use git-bisect to see which commit introduces this bug?<br>
</blockquote></div><br>Is this really necessary? I am not sure I can get my hands on this machine.<br>It seems pretty clear where the circular dependency is -<br>the real question is IMO what the right fix is.<br><br></div>
On Monday 16 March 2009, Michael S. Tsirkin wrote:
> On Sat, Mar 14, 2009 at 08:05:29PM +0100, Rafael J. Wysocki wrote:
> > This message has been generated automatically as a part of a report
> > of recent regressions.
> >
> > The following bug entry is on the current list of known regressions
> > from 2.6.28. Please verify if it still should be listed and let me know
> > (either way).
> >
> >
> > Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=12574
> > Subject : possible circular locking dependency detected
> > Submitter : Michael S. Tsirkin <m.s.tsirkin@gmail.com>
> > Date : 2009-01-29 11:35 (45 days old)
> > References : http://lkml.org/lkml/2009/2/9/205
> >
>
> It's still there in rc8.
It seems we can't proceed any further here. Closing. |
Latest working kernel version: 2.6.28 Earliest failing kernel version: 2.6.29-rc3 Distribution: ubuntu gutsy Hardware Environment: thinkpad T60p Software Environment: lockdep enabled Problem Description: after suspend/resume, circular lock dependency warning appears in dmesg output: [ 2108.325226] ACPI: Preparing to enter system sleep state S3 [ 2108.345297] Disabling non-boot CPUs ... [ 2108.345692] [ 2108.345694] ======================================================= [ 2108.345697] [ INFO: possible circular locking dependency detected ] [ 2108.345702] 2.6.29-rc3-mst-debug #94 [ 2108.345705] ------------------------------------------------------- [ 2108.345708] bash/6787 is trying to acquire lock: [ 2108.345712] (&per_cpu(cpu_policy_rwsem, cpu)){----}, at: [<c02c02b1>] lock_policy_rwsem_write+0x31/0x70 [ 2108.345727] [ 2108.345729] but task is already holding lock: [ 2108.345732] (&cpu_hotplug.lock){--..}, at: [<c012d7ea>] cpu_hotplug_begin+0x1a/0x50 [ 2108.345741] [ 2108.345742] which lock already depends on the new lock. [ 2108.345744] Full message and .config will attached. Steps to reproduce: suspend, resume.