Any ideas about this? (i915 caused kernel oops while suspending to RAM)

[Chris Wilson]

On Tue, 22 Mar 2011 22:21:24 +0100, Łukasz Maśko <ed at yen.ipipan.waw.pl> wrote:
> It says (or at leas it seems so) that it was the i915 graphics drm module 
> which caused it. My machine has i945GM graphics chipset. Currently I'm 
> running xserver 1.10.0 and intel driver 2.14.0. Both of these oopses 
> happened with 2.6.37.4 kernel, which I've been using since Saturday. There 
> were no such problems with earlier kernels.

You were fortunate, as the bug in all its guises is much older indeed.
The final fix, I hope, was:

commit 9334ef755f060e251f3f395caeda1a58b6834ea3
Author: Chris Wilson <chris at chris-wilson.co.uk>
Date:   Fri Jan 28 11:53:03 2011 +0000

    drm: Don't switch fb when disabling an output
    
    In drm_crtc_helper_set_config, we call drm_crtc_helper_set_mode which
    may return early and do no operation if the crtc is to be disabled. In
    this case we merrily swap to the new fb, discarding the old_fb believing
    that it has been cleaned up. However, due to the early return, the
    old_fb was not presented to the backend for correct reaping, and nor was
    the new one - which is about to be reaped via the
    drm_helper_disable_unused_functions(), leading to incorrect refcounting
    of the pinned objects.
    
    Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=27722
    Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=29857
    Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=29230
    Tested-by: Takashi Iwai <tiwai at suse.de>
    Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>

-- 
Chris Wilson, Intel Open Source Technology Centre