lockdep warning during elevator_switch
Hugh Dickins
I "echo deadline >/sys/block/sdb/queue/scheduler" to change it from cfq.
Backing out 846f99749ab68bbc7f75c74fec305de675b1a1bf "sysfs: Add lockdep
annotations for the sysfs active reference" stops the warning -
but I realize that doesn't mean the actual problem (if any) is fixed.
(An orthogonal irritation which I don't recall anyone mentioning before:
lockdep's stacktrace involves a console_verbose() to make sure it goes to
console, which is never cancelled: so from that point on my console is
spammed with wireless authentication debug messages every twenty minutes.
But perhaps that's a feature, without which I'd have ignored the lockdep
report for longer; and /proc/sys/kernel/printk can restore the loglevel.)
Hugh
=============================================
[ INFO: possible recursive locking detected ]
2.6.33-rc6 #1
---------------------------------------------
sh/889 is trying to acquire lock:
(s_active){++++.+}, at: [<7820a975>] sysfs_addrm_finish+0x27/0x4e
but task is already holding lock:
(s_active){++++.+}, at: [<7820ab82>] sysfs_get_active_two+0x18/0x3e
other info that might help us debug this:
4 locks held by sh/889:
#0: (&buffer->mutex){+.+.+.}, at: [<7820984e>] sysfs_write_file+0x20/0x99
#1: (s_active){++++.+}, at: [<7820ab82>] sysfs_get_active_two+0x18/0x3e
#2: (s_active){++++.+}, at: [<7820ab91>] sysfs_get_active_two+0x27/0x3e
#3: (&q->sysfs_lock){+.+.+.}, at: [<78289e95>] queue_attr_store+0x2e/0x68
stack backtrace:
Pid: 889, comm: sh Not tainted 2.6.33-rc6 #1
Call Trace:
[<784a6966>] ? printk+0xf/0x11
[<781752a1>] print_deadlock_bug+0x99/0xa3
[<781753c6>] check_deadlock+0x11b/0x140
[<781763e5>] validate_chain+0x4ec/0x4f9
[<78176a68>] __lock_acquire+0x676/0x6cf
[<78176b64>] lock_acquire+0xa3/0xbc
[<7820a975>] ? sysfs_addrm_finish+0x27/0x4e
[<7820a37a>] sysfs_deactivate+0x6c/0xa4
[<7820a975>] ? sysfs_addrm_finish+0x27/0x4e
[<7820a975>] sysfs_addrm_finish+0x27/0x4e
[<7820aa3a>] sysfs_remove_dir+0x62/0x72
[<7829d6dd>] kobject_del+0x11/0x32
[<78283406>] __elv_unregister_queue+0x18/0x20
[<78283c66>] elevator_switch+0x6d/0x11b
[<78283d92>] elv_iosched_store+0x7e/0x9b
[<78289eb8>] queue_attr_store+0x51/0x68
[<78209894>] sysfs_write_file+0x66/0x99
[<781cd460>] vfs_write+0x8a/0x108
[<781cd578>] sys_write+0x3c/0x63
[<78125b90>] sysenter_do_call+0x12/0x36
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Rafael J. Wysocki
of recent regressions.
The following bug entry is on the current list of known regressions
from 2.6.32. Please verify if it still should be listed and let me know
(either way).
Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=15202
Subject : lockdep warning during elevator_switch
Submitter : Hugh Dickins <hugh.d...@tiscali.co.uk>
Date : 2010-01-31 23:55 (1 days old)
References : http://marc.info/?l=linux-kernel&m=126498212613051&w=4
Rafael J. Wysocki
of recent regressions.
The following bug entry is on the current list of known regressions
from 2.6.32. Please verify if it still should be listed and let me know
(either way).
Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=14792
Subject : Misdetection of the TV output
Submitter : Santi <sa...@agolina.net>
Date : 2009-12-12 13:28 (51 days old)
First-Bad-Commit: http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=27dfaf4f5825a119305db1bc63bef30ed400e376
Handled-By : Zhao Yakui <yakui...@intel.com>
Rafael J. Wysocki
of recent regressions.
The following bug entry is on the current list of known regressions
from 2.6.32. Please verify if it still should be listed and let me know
(either way).
Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=15043
Subject : Display goes off with i915.powersave=1 after suspend-resume
Submitter : Soeren Sonnenburg <so...@debian.org>
Date : 2010-01-10 20:09 (22 days old)
References : http://marc.info/?l=linux-kernel&m=126315457519505&w=4
Rafael J. Wysocki
of recent regressions.
The following bug entry is on the current list of known regressions
from 2.6.32. Please verify if it still should be listed and let me know
(either way).
Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=14950
Subject : tbench regression with 2.6.33-rc1
Submitter : Lin Ming <ming....@intel.com>
Date : 2009-12-25 11:11 (38 days old)
References : http://marc.info/?l=linux-kernel&m=126174044213172&w=4
Rafael J. Wysocki
of recent regressions.
The following bug entry is on the current list of known regressions
from 2.6.32. Please verify if it still should be listed and let me know
(either way).
Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=15119
Subject : iwl_bg_scan_completed: WARN on scan complete
Submitter : Alex Zhavnerchik <alex....@gmail.com>
Date : 2010-01-24 12:27 (8 days old)
Rafael J. Wysocki
of recent regressions.
The following bug entry is on the current list of known regressions
from 2.6.32. Please verify if it still should be listed and let me know
(either way).
Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=15199
Subject : sata_nv and no /dev files
Submitter : Bartłomiej Zimoń <uz...@o2.pl>
Date : 2010-01-31 23:45 (1 days old)
References : http://marc.info/?l=linux-kernel&m=126498153112488&w=4
Rafael J. Wysocki
of recent regressions.
The following bug entry is on the current list of known regressions
from 2.6.32. Please verify if it still should be listed and let me know
(either way).
Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=14791
Subject : Something has been broken in the network stack this week
Submitter : Delete This Account <speedybo...@hotmail.com>
Date : 2009-12-12 13:06 (51 days old)
Handled-By : Ben Hutchings <b...@decadent.org.uk>
Patch : http://patchwork.kernel.org/patch/72073/
Rafael J. Wysocki
of recent regressions.
The following bug entry is on the current list of known regressions
from 2.6.32. Please verify if it still should be listed and let me know
(either way).
Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=15192
Subject : netperf ~50% regression with 2.6.33-rc1, bisect to 1b9508f
Submitter : Lin Ming <ming....@intel.com>
Date : 2010-01-25 10:03 (7 days old)
First-Bad-Commit: http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=1b9508f6831e10d53256825de8904caa22d1ca2c
References : http://marc.info/?l=linux-kernel&m=126441481427331&w=4
Handled-By : Mike Galbraith <efa...@gmx.de>
Peter Zijlstra <pet...@infradead.org>
Rafael J. Wysocki
of recent regressions.
The following bug entry is on the current list of known regressions
from 2.6.32. Please verify if it still should be listed and let me know
(either way).
Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=15198
Subject : Radeon KMS regression
Submitter : Kevin Winchester <kjwinc...@gmail.com>
Date : 2010-01-30 17:18 (2 days old)
First-Bad-Commit: http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=42590a75019a50012f25a962246498dead428433
References : http://marc.info/?l=linux-kernel&m=126487191019612&w=4
Handled-By : FUJITA Tomonori <fujita....@lab.ntt.co.jp>
Patch : http://patchwork.kernel.org/patch/75023/
Ben Hutchings
> 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 2.6.32. Please verify if it still should be listed and let me know
> (either way).
>
>
> Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=14791
> Subject : Something has been broken in the network stack this week
> Submitter : Delete This Account <speedybo...@hotmail.com>
> Date : 2009-12-12 13:06 (51 days old)
> Handled-By : Ben Hutchings <b...@decadent.org.uk>
> Patch : http://patchwork.kernel.org/patch/72073/
Dave has accepted the patch but hasn't pushed it out yet. I expect that
it will be in 2.6.33-rc7.
Ben.
--
Ben Hutchings
Unix is many things to many people,
but it's never been everything to anybody.
Mike Galbraith
> 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 2.6.32. Please verify if it still should be listed and let me know
> (either way).
Yes, it should remain open. Looking for places to trim overhead without
injuring other things. The regression is a moving target on my HW.
-Mike
Mike Galbraith
> of recent regressions.
>
> The following bug entry is on the current list of known regressions
> from 2.6.32. Please verify if it still should be listed and let me know
> (either way).
Yes, it should remain open. We're currently waiting for some data from
Lin Ming. The regression itself isn't making much sense.. a kernel with
NEWIDLE disabled should show the same performance, but does not.
-Mike
Kevin Winchester
> of recent regressions.
>
> The following bug entry is on the current list of known regressions
> from 2.6.32. Please verify if it still should be listed and let me know
> (either way).
>
>
> Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=15198
> Subject : Radeon KMS regression
> Submitter : Kevin Winchester <kjwinc...@gmail.com>
> Date : 2010-01-30 17:18 (2 days old)
> First-Bad-Commit: http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=42590a75019a50012f25a962246498dead428433
> References : http://marc.info/?l=linux-kernel&m=126487191019612&w=4
> Handled-By : FUJITA Tomonori <fujita....@lab.ntt.co.jp>
> Patch : http://patchwork.kernel.org/patch/75023/
>
>
This is fixed by the patch from FUJITA Tomonori - I just confirmed with
my latest build of Linus' tree (which has the patch).
Thanks,
--
Kevin Winchester
Rafael J. Wysocki
> On Mon, 2010-02-01 at 01:22 +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 2.6.32. Please verify if it still should be listed and let me know
> > (either way).
> >
> >
> > Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=15198
> > Subject : Radeon KMS regression
> > Submitter : Kevin Winchester <kjwinc...@gmail.com>
> > Date : 2010-01-30 17:18 (2 days old)
> > First-Bad-Commit: http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=42590a75019a50012f25a962246498dead428433
> > References : http://marc.info/?l=linux-kernel&m=126487191019612&w=4
> > Handled-By : FUJITA Tomonori <fujita....@lab.ntt.co.jp>
> > Patch : http://patchwork.kernel.org/patch/75023/
> >
> >
>
> This is fixed by the patch from FUJITA Tomonori - I just confirmed with
> my latest build of Linus' tree (which has the patch).
Thanks, already closed.
Rafael
Rafael J. Wysocki
> On Mon, 2010-02-01 at 01:22 +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 2.6.32. Please verify if it still should be listed and let me know
> > (either way).
>
> Yes, it should remain open. We're currently waiting for some data from
> Lin Ming. The regression itself isn't making much sense.. a kernel with
> NEWIDLE disabled should show the same performance, but does not.
Well, thanks for the update.
Rafael
Rafael J. Wysocki
> > 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 2.6.32. Please verify if it still should be listed and let me know
> > (either way).
>
> Yes, it should remain open. Looking for places to trim overhead without
> injuring other things. The regression is a moving target on my HW.
Thanks for the update.
Rafael
Jens Axboe
> From 2.6.33-rc3 onwards, PROVE_LOCKING=y gives me the warning below when
> I "echo deadline >/sys/block/sdb/queue/scheduler" to change it from cfq.
>
> Backing out 846f99749ab68bbc7f75c74fec305de675b1a1bf "sysfs: Add lockdep
> annotations for the sysfs active reference" stops the warning -
> but I realize that doesn't mean the actual problem (if any) is fixed.
Thanks Hugh, I hadn't noticed this yet. I do online switches all the
time, but depending on tests lockdep may not be enabled (it steals all
my performance...). I'll take a look.
--
Jens Axboe
Soeren Sonnenburg
> of recent regressions.
>
> The following bug entry is on the current list of known regressions
> from 2.6.32. Please verify if it still should be listed and let me know
> (either way).
>
>
> Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=15043
> Subject : Display goes off with i915.powersave=1 after suspend-resume
> Submitter : Soeren Sonnenburg <so...@debian.org>
> Date : 2010-01-10 20:09 (22 days old)
> References : http://marc.info/?l=linux-kernel&m=126315457519505&w=4
yes still exists in current git.
Soeren
--
For the one fact about the future of which we can be certain is that it
will be utterly fantastic. -- Arthur C. Clarke, 1962
Rafael J. Wysocki
> On Mon, 2010-02-01 at 01:22 +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 2.6.32. Please verify if it still should be listed and let me know
> > (either way).
> >
> >
> > Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=15043
> > Subject : Display goes off with i915.powersave=1 after suspend-resume
> > Submitter : Soeren Sonnenburg <so...@debian.org>
> > Date : 2010-01-10 20:09 (22 days old)
> > References : http://marc.info/?l=linux-kernel&m=126315457519505&w=4
>
> yes still exists in current git.
Thanks for the update.
Rafael
Jesse Barnes
"Rafael J. Wysocki" <r...@sisk.pl> wrote:
> On Thursday 04 February 2010, Soeren Sonnenburg wrote:
> > On Mon, 2010-02-01 at 01:22 +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 2.6.32. Please verify if it still should be
> > > listed and let me know (either way).
> > >
> > >
> > > Bug-Entry :
> > > http://bugzilla.kernel.org/show_bug.cgi?id=15043
> > > Subject : Display goes off with i915.powersave=1
> > > after suspend-resume Submitter : Soeren Sonnenburg
> > > <so...@debian.org> Date : 2010-01-10 20:09 (22
> > > days old) References :
> > > http://marc.info/?l=linux-kernel&m=126315457519505&w=4
> >
> > yes still exists in current git.
>
> Thanks for the update.
Just updated the corresponding FDO bug
(https://bugs.freedesktop.org/show_bug.cgi?id=24314). There are some
hw bugs related to FBC handling on 945GM though, so we may have to
disable it on some machines.
--
Jesse Barnes, Intel Open Source Technology Center
Soeren Sonnenburg
> On Thu, 4 Feb 2010 21:42:02 +0100
> "Rafael J. Wysocki" <r...@sisk.pl> wrote:
>
> > On Thursday 04 February 2010, Soeren Sonnenburg wrote:
> > > On Mon, 2010-02-01 at 01:22 +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 2.6.32. Please verify if it still should be
> > > > listed and let me know (either way).
> > > >
> > > >
> > > > Bug-Entry :
> > > > http://bugzilla.kernel.org/show_bug.cgi?id=15043
> > > > Subject : Display goes off with i915.powersave=1
> > > > after suspend-resume Submitter : Soeren Sonnenburg
> > > > <so...@debian.org> Date : 2010-01-10 20:09 (22
> > > > days old) References :
> > > > http://marc.info/?l=linux-kernel&m=126315457519505&w=4
> > >
> > > yes still exists in current git.
> >
> > Thanks for the update.
>
> Just updated the corresponding FDO bug
> (https://bugs.freedesktop.org/show_bug.cgi?id=24314). There are some
> hw bugs related to FBC handling on 945GM though, so we may have to
> disable it on some machines.
FYI: With the patch from #14897 it was working for the last day and a
half at least...
Lin Ming
> On Mon, 2010-02-01 at 01:22 +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 2.6.32. Please verify if it still should be listed and let me know
> > (either way).
>
> Yes, it should remain open. We're currently waiting for some data from
> Lin Ming. The regression itself isn't making much sense.. a kernel with
> NEWIDLE disabled should show the same performance, but does not.
(sorry for late response, I'm just back from vacation)
We finally located this to a bug in mwait based C-state entry.
Venki's patch has fixed it.
http://patchwork.kernel.org/patch/78544/
Venki, this is the original report,
http://marc.info/?l=linux-kernel&m=126441481427331&w=4
Thanks,
Lin Ming
Mike Galbraith
> On Mon, 2010-02-01 at 16:04 +0800, Mike Galbraith wrote:
> > On Mon, 2010-02-01 at 01:22 +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 2.6.32. Please verify if it still should be listed and let me know
> > > (either way).
> >
> > Yes, it should remain open. We're currently waiting for some data from
> > Lin Ming. The regression itself isn't making much sense.. a kernel with
> > NEWIDLE disabled should show the same performance, but does not.
>
> (sorry for late response, I'm just back from vacation)
>
> We finally located this to a bug in mwait based C-state entry.
> Venki's patch has fixed it.
> http://patchwork.kernel.org/patch/78544/
>
> Venki, this is the original report,
> http://marc.info/?l=linux-kernel&m=126441481427331&w=4
Excellent, mystery solved. (adds acpi)
-Mike