Re: [2/3] 2.6.22-rc1: known regressions v2

Re: [2/3] 2.6.22-rc1: known regressions v2

[Michal Piotrowski]

Hi all,

Here is a list of some known regressions in 2.6.22-rc1.

Feel free to add new regressions/remove fixed etc.
http://kernelnewbies.org/known_regressions



File systems

Subject    : 2.6.21-git10/11: files getting truncated on xfs
References : http://lkml.org/lkml/2007/5/9/410
Submitter  : Jeremy Fitzhardinge <jeremy@goop.org>
Handled-By : David Chinner <dgc@sgi.com>
Patch      : http://lkml.org/lkml/2007/5/12/93
Status     : patch was suggested



Memory management

Subject    : kernel BUG at include/linux/slub_def.h:88 kmalloc_index()
References : http://bugzilla.kernel.org/show_bug.cgi?id=8476
Submitter  : Cherwin R. Nooitmeer <cherwin@gmail.com>
Status     : Unknown



SATA/PATA

Subject    : libata crash on halt
References : http://marc.info/?l=linux-ide&m=117899827710565&w=2
Submitter  : Andrew Morton <akpm@linux-foundation.org>
Caused-By  : Tejun Heo <htejun@gmail.com>
             commit 920a4b1038e442700a1cfac77ea7e20bd615a2c3
Status     : problem is being debugged

Subject    : libata reset-seq merge broke sata_sil on sh
References : http://lkml.org/lkml/2007/5/10/63
Submitter  : Paul Mundt <lethal@linux-sh.org>
Handled-By : Tejun Heo <htejun@gmail.com>
Caused-By  : commit 4750def52cb2c21732dda9aa1d43a07db37b0186
Status     : problem is being debugged



Suspend

Subject    : Broken suspend on SMP with tifm
References : http://lkml.org/lkml/2007/5/13/161
Submitter  : Rafael J. Wysocki <rjw@sisk.pl>
Status     : patch was suggested



Regards,
Michal

--
Michal K. K. Piotrowski
Kernel Monkeys
(http://kernel.wikidot.com/start)

Re: [3/3] 2.6.22-rc1: known regressions v2

[Michal Piotrowski]

Hi all,

Here is a list of some known regressions in 2.6.22-rc1.

Feel free to add new regressions/remove fixed etc.
http://kernelnewbies.org/known_regressions



Timers/NOHZ

Subject    : 2.6.21-git4 BUG: soft lockup detected on CPU#1! 
References : http://lkml.org/lkml/2007/5/2/511
Submitter  : Michal Piotrowski <michal.k.k.piotrowski@gmail.com>
Handled-By : Thomas Gleixner <tglx@linutronix.de>
Status     : problem is being debugged



USB

Subject    : usb hotplug/udev cannot correctly register usb/scanners
References : http://lkml.org/lkml/2007/5/15/205
Submitter  : art@usfltd.com <art@usfltd.com>
Status     : Unknown



V4L

Subject    : V4L ABI breakage
References : http://lkml.org/lkml/2007/5/14/42
Submitter  : Robert Fitzsimons <robfitz@273k.net>
Caused-By  : Hans Verkuil <hverkuil@xs4all.nl>
             Mauro Carvalho Chehab <mchehab@infradead.org>
             commit 206ebaf32795cf1582b1e2ff2ec6a560c9e986b8
Status     : Unknown



Networking

Subject    : panic with e1000 driver on HP Integrity servers
References : http://bugzilla.kernel.org/show_bug.cgi?id=8455
Submitter  : Doug Chapman <doug.chapman@hp.com>
Caused-By  : Auke Kok <auke-jan.h.kok@intel.com>
             commit e0aac5a289b1dacbc94bd9ae8c449bcdf9ab508c
Status     : problem is being debugged



Regards,
Michal

--
Michal K. K. Piotrowski
Kernel Monkeys
(http://kernel.wikidot.com/start)

Re: [2/3] 2.6.22-rc1: known regressions v2

[Christoph Lameter]

On Wed, 16 May 2007, Michal Piotrowski wrote:

> Memory management
> 
> Subject    : kernel BUG at include/linux/slub_def.h:88 kmalloc_index()
> References : http://bugzilla.kernel.org/show_bug.cgi?id=8476
> Submitter  : Cherwin R. Nooitmeer <cherwin@gmail.com>
> Status     : Unknown


This a kmalloc(0) that needs fixing.

Re: [3/3] 2.6.22-rc1: known regressions v2

[Mauro Carvalho Chehab]

Hi Michal,


> V4L
>
> Subject    : V4L ABI breakage
> References : http://lkml.org/lkml/2007/5/14/42
> Submitter  : Robert Fitzsimons <robfitz@273k.net>
> Caused-By  : Hans Verkuil <hverkuil@xs4all.nl>
>             Mauro Carvalho Chehab <mchehab@infradead.org>
>             commit 206ebaf32795cf1582b1e2ff2ec6a560c9e986b8
> Status     : Unknown

We are currently working on it. I expect to have a patch fixing the issue 
until next week.

Cheers,
Mauro.

Re: [2/3] 2.6.22-rc1: known regressions v2

[Linus Torvalds]

On Wed, 16 May 2007, Christoph Lameter wrote:

> On Wed, 16 May 2007, Michal Piotrowski wrote:
> 
> > Memory management
> > 
> > Subject    : kernel BUG at include/linux/slub_def.h:88 kmalloc_index()
> > References : http://bugzilla.kernel.org/show_bug.cgi?id=8476
> > Submitter  : Cherwin R. Nooitmeer <cherwin@gmail.com>
> > Status     : Unknown
> 
> 
> This a kmalloc(0) that needs fixing.

Well, "needs fixing" is a bit strong.

It's a scary message for something we've always handled, and that we still 
handle fine, we just complain about it.

So we'll probably just turn the message off for 2.6.22, but in the 
meantime, we leave it on and try to fix as many of these as we can be 
bothered to.

		Linus

Re: [2/3] 2.6.22-rc1: known regressions v2 - XFS

[David Chinner]

On Wed, May 16, 2007 at 10:31:39PM +0200, Michal Piotrowski wrote:
> Hi all,
> 
> Here is a list of some known regressions in 2.6.22-rc1.
> 
> Feel free to add new regressions/remove fixed etc.
> http://kernelnewbies.org/known_regressions
> 
> File systems
> 
> Subject    : 2.6.21-git10/11: files getting truncated on xfs
> References : http://lkml.org/lkml/2007/5/9/410
> Submitter  : Jeremy Fitzhardinge <jeremy@goop.org>
> Handled-By : David Chinner <dgc@sgi.com>
> Patch      : http://lkml.org/lkml/2007/5/12/93
> Status     : patch was suggested

Jeremy has tentatively indicated that the patch has fixed the problem.
Have you seen any more problems since applying the patch, Jeremy?

Cheers,

Dave.
-- 
Dave Chinner
Principal Engineer
SGI Australian Software Group

Re: [2/3] 2.6.22-rc1: known regressions v2 - XFS

[Jeremy Fitzhardinge]

David Chinner wrote:
> Jeremy has tentatively indicated that the patch has fixed the problem.
> Have you seen any more problems since applying the patch, Jeremy?
>   

No, it continues to seem sound with casual use; I would have expected to
see the problem reoccur by now.  I'd like to rerun the full set of tests
I did before to be sure, but so far so good.  No other apparent
regressions either.

Also, the match between the observed symptoms and the bugfix is very
good, which adds confidence (ie, no element of "it works now but we
don't know why").  I guess the only remaining concern is whether there
are any other paths which fail to dirty the inode.

Did you manage to repro the problem?

    J

Re: [2/3] 2.6.22-rc1: known regressions v2 - XFS

[David Chinner]

On Wed, May 16, 2007 at 04:40:20PM -0700, Jeremy Fitzhardinge wrote:
> David Chinner wrote:
> > Jeremy has tentatively indicated that the patch has fixed the problem.
> > Have you seen any more problems since applying the patch, Jeremy?
> >   
> 
> No, it continues to seem sound with casual use; I would have expected to
> see the problem reoccur by now.  I'd like to rerun the full set of tests
> I did before to be sure, but so far so good.  No other apparent
> regressions either.

Good to here. I think the problem is fixed, then.

> Also, the match between the observed symptoms and the bugfix is very
> good, which adds confidence (ie, no element of "it works now but we
> don't know why").  I guess the only remaining concern is whether there
> are any other paths which fail to dirty the inode.

There aren't any that I can see - if more come up we'll deal with
them then.

> Did you manage to repro the problem?

xfs_io is my friend ;)

Without patch:

# touch /mnt/scratch/fred
# xfs_io -c "pwrite 0 5" -c "s" -c "pwrite 5 5" /mnt/scratch/fred
wrote 5/5 bytes at offset 0
5.000000 bytes, 1 ops; 0.0000 sec (78.755 KiB/sec and 16129.0323 ops/sec)
wrote 5/5 bytes at offset 5
5.000000 bytes, 1 ops; 0.0000 sec (542.535 KiB/sec and 111111.1111 ops/sec)
# umount /mnt/scratch; mount /mnt/scratch; ls -l /mnt/scratch/fred
-rw-r--r-- 1 root      root      5 May 17 10:04 fred
#

So the second 5 byte write didn't change the file size.

With patch:

# touch /mnt/scratch/fred
# xfs_io -c "pwrite 0 5" -c "s" -c "pwrite 5 5" /mnt/scratch/fred
wrote 5/5 bytes at offset 0
5.000000 bytes, 1 ops; 0.0000 sec (76 KiB/sec and 15625.0000 ops/sec)
wrote 5/5 bytes at offset 5
5.000000 bytes, 1 ops; 0.0000 sec (610 KiB/sec and 125000.0000 ops/sec)
# umount /mnt/scratch; mount /mnt/scratch; ls -l /mnt/scratch/fred
-rw-r--r-- 1 root      root     10 May 17 09:53 fred
#

So yes, I've reproduced it and confirmed the patch fixes the problem.

Cheers,

Dave.
-- 
Dave Chinner
Principal Engineer
SGI Australian Software Group