Bug#630360: linux-2.6: sporadic kernel bug while trying to hibernate system

[Jonathan Nieder <jrnieder@gmail.com>]

retitle 630360 linux: intermittent BUG at kernel/power/snapshot.c:528 when trying to hibernate
found 630360 linux-2.6/2.6.39-2
# based on the above messages
quit

Hi Daniel,

Daniel Schoepe wrote:

> I am also affected by this bug and it seems to occur if and only if I
> try to hibernate with more than about 50% of my RAM in use. This is the
> configured "Preferred maximum image size" for uswsusp on my system, but
> changing it to a higher value does not prevent it.

So it's a regression from squeeze and 100% reproducible?  From the
point of view of fixing it, that's excellent news.

Except for the list of affected versions, this looks like
[*] https://bugzilla.kernel.org/show_bug.cgi?id=15816.  If you have
time, could you do the following?

 - first, test the latest kernel from experimental

 - find the first affected upstream release by running a bisection
   search through packages at snapshot.debian.org

 - try the debugging patch from Raphael Wysoki's upsteam [*]
   comment #7, using instructions from here:

	http://kernel-handbook.alioth.debian.org/ch-common-tasks.html#s-common-building

   and Documentation/applying-patches.txt and let Raphael know
   the result and details about your case (e.g., by commenting on the
   upstream report).

 - try using "git bisect" to find out which upstream change
   introduced the bug, like so:

	$ apt-get install git build-essential
	$ git clone git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git
	$ cd linux-2.6
	$ make localmodconfig; # minimal configuration
	$ make deb-pkg
	$ cd ..; dpkg -i <produced package>; reboot
	$ ... test test test ...

	If it works at this point, declare victory and let us know.

	$ git bisect start
	$ git bisect bad; # tell git the good news
	$ git checkout v2.6.32; # or whatever version you think will work
	$ make silentoldconfig
	$ make && fakeroot -u make deb-pkg
	$ cd ..; dpkg -i <produced package>; reboot
	$ ... test test test ...

	Hopefully that one does not trigger the BUG.

	$ git bisect good; # tell git the good news

	Then it will automatically check out a revision half-way, so:

	$ make silentoldconfig
	$ make && fakeroot -u make deb-pkg
	$ cd ..; dpkg -i <produced package>; reboot
	$ ... test test test ...
	$ git bisect bad; # if it triggers the BUG, or
	$ git bisect good; # if working hard still does not trigger the BUG, or
	$ git bisect skip; # if some other bug makes it hard to test

	Rinse and repeat until it tells the "first bad commit" or you
	get bored and let us know the outcome plus "git bisect log"
	output.

	If the gitk package is installed, you can use "git bisect visualize"
	to see the regression range narrow at each step.  See
	http://www.kernel.org/pub/software/scm/git/docs/git-bisect-lk2009.html
	for more details.

Thanks for reporting and hope that helps.
Jonathan