Bug#650061: [3.0 -> 3.1.1] Regression in suspend with rtl8192se driver

[Jonathan Nieder <jrnieder@gmail.com>]

Hi,

Kapil Hari Paranjape wrote:

> After the upgrade from linux-3.0.0-1-amd64 to linux-3.1.0-1-amd64,
> the (kernel-based) suspend/suspend stopped working on my laptop.
>
> I could track it down to the rtl8192se module.

Nice.

There have been some rtl8192se fixes upstream, though none that seem
too relevant.  Please test v3.2-rc1 or later once it hits
experimental, or sooner if you have time to build from source.

If it exhibits the same problem, please report this upstream.  From
the MAINTAINERS file it seems that means to contact
linux-wireless@vger.kernel.org, cc-ing Larry Finger
<Larry.Finger@lwfinger.net>, Chaoming Li <chaoming_li@realsil.com.cn>,
linux-kernel@vger.kernel.org, and either me or this bug log so we can
track it.

If you have time to bisect, even better.

	apt-get install build-essential git

	git clone \
	  git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
	cd linux
	git checkout origin/master
	make localmodconfig; # minimal configuration
	make deb-pkg; # can use -j2 for parallel build
	dpkg -i ../<name of package>
	reboot
	... test ...

	# if it works, declare victory.  Otherwise:
	git checkout v3.0
	make silentoldconfig; # reuse configuration
	make deb-pkg
	dpkg -i ../<name of package>

	# hopefully it fails.  So:
	git bisect start origin/master v3.0 -- drivers/net/wireless/rtlwifi
	# it helpfully checks out a revision halfway between to test
	make silentoldconfig; # reuse configuration
	make deb-pkg
	dpkg -i ../<name of package>
	reboot
	... test ...

	git bisect good; # if it suspends successfully
	git bisect bad; # if it fails in the same way
	git bisect skip; # if some other bug makes it hard to test

	# next round
	make silentoldconfig
	make deb-pkg
	dpkg -i ../<name of package>
	reboot
	... test ...
	git bisect good / bad / skip

Eventually it will point out the patch that seems to have introduced
the bug, so you can mention it and cc its author along with everyone
else when reporting this upstream and it will get fixed extra quickly.
:)  If you have the gitk package installed you can run "git bisect
visualize" to see the regression range narrowing and check out commits
to test more strategically.  If you get bored, "git bisect visualize"
will print a log of the commits you've tested so far and that
information is helpful already.  Even a few rounds of bisection can
help a lot in narrowing down the cause of a bug.

Hope that helps,
Jonathan