Re: [BISECTED] x11 fbdev on intelfb hangs hard after 66c1ca019078220dc1bf968f2bb18421100ef147

[Andrea Righi <righi.andrea@gmail.com>]

On Thu, Apr 09, 2009 at 06:02:04PM -0400, Pavel Roskin wrote:
> Hello!
> 
> I'm running the latest wireless-testing.git kernel, which is 2.6.30-rc1
> plus some wireless bits.  I use intelfb with kernel mode switching and
> X11 using fbdev.  This runs on Fedora 10, fbdev driver is
> xorg-x11-drv-fbdev-0.3.1-7.fc9.x86_64.
> 
> This worked fine with Linux 2.6.29, but after upgrading to 2.6.30-rc1
> X11 hangs hard.
> 
> Bisecting found commit 66c1ca019078220dc1bf968f2bb18421100ef147 to be
> responsible.  It can be reverted on top of 2.6.30-rc1, and the resulting
> kernel is working fine.  The commit is called:
> 
> fbmem: fix fb_info->lock and mm->mmap_sem circular locking dependency
> 
> I'm especially concerned to see stable@kernel.org in the cc in the log.
> This patch fails on two systems for me, so it's hardly ready for stable
> kernels.
> 
> The kernel config (very minimal, I used it to speed up bisecting),
> xorg.conf and lspci output are attached.

Thanks for reporting Pavel. I agree to revert 66c1ca ASAP.

See also http://lkml.org/lkml/2009/4/9/177.

-Andrea