Re: Suspend to disk broken in latest 2.6.28-rc3

[Jesse Barnes <jbarnes@virtuousgeek.org>]

On Monday, November 10, 2008 2:13 pm Mathieu Chouquet-Stringer wrote:
> On Mon, Nov 10, 2008 at 10:42:39AM +0100, Pavel Machek wrote:
> > Trying with minimum drivers is likely to help here, and should be
> > easier than bisect. Boot with init=/bin/bash, then try "devices" >
> > pm_dest and disk > state...
>
> Some progress with (2.6.28-rc4 this time)...  I've booted with /bin/bash
> as init: works.
>
> Then I rebooted in single mode => works
> Runlevel 3 => works
> Runlevel 5 => doesn't work
>
> In terms of devices, lsmod says the only differences between runlevel 3
> and runlevel 5 are that both drm and radeon are loaded...
>
> If I rmmod radeon and drm while X is running suspending the devices
> works...  I guess I don't have DRI enabled???  Just looked at the logs,
> I guess I don't [1]...
>
> Looking at a git log -p of gpu/drm/radeon shows lots of difference
> between 2.6.26 and HEAD...  I see a vblank change [2] that changes the
> way the device is suspended, not sure if it really matters though...
>
> Alex, Jesse and/or Dave can you think of anything before I bisect?  FYI
> my radeon is a:
> ATI Technologies Inc Radeon Mobility M7 LW [Radeon Mobility 7500] rev 0,

If you have radeon loaded but DRI was never enabled, you'll likely see a 
crash.  That's because the radeon driver doesn't map the registers it needs 
for suspend/resume at load time; they only get mapped by DRI initialization 
code which lives in the X driver.  There's a patch in 
http://bugzilla.kernel.org/show_bug.cgi?id=11891 that might help you...

-- 
Jesse Barnes, Intel Open Source Technology Center