WARNING: at drivers/gpu/drm/drm_crtc.c:82 drm_warn_on_modeset_not_all_locked+0x8d/0xc0()

[Dave Airlie]

On Thu, May 2, 2013 at 10:41 AM, Daniel Vetter <daniel at ffwll.ch> wrote:
> On Thu, May 2, 2013 at 2:02 AM, Borislav Petkov <bp at alien8.de> wrote:
>> Hi,
>>
>> I'm seeing this when booting latest Linus tree + tip/master in kvm.
>> Config is attached. Looks like it cannot find root fs and panics and
>> calls the panic notifier which screams in drm_crtc.c because not all
>> modeset locks are taken. Maybe bogus?
>
> Locking in the drm panic notifiere is completely bogus (as in simply
> does not exist). The only difference is that with the new locking
> scheme in 3.9 we're now pretty obnixious about checking for these
> kinds of things. Also, drm drivers love to sleep in the panic
> handlers, too. It's somewhere on my giant list of things to fix in drm
> land, but I'm not sure whether I'll get around to it in this life or
> the next. Maybe we just need to shut up the WARN in case of a panic
> ...

Maybe? of course you do.

its a panic, getting anything on the screen is vastly more important than
the locking being perfect, any chance of any info landing on the screen
is being decreased by this spew.

Dave.