[PATCH] drm/amdgpu: fix check in fbdev init

[Alex Deucher]

On Wed, Aug 10, 2022 at 11:38 AM Greg KH <gregkh at linuxfoundation.org> wrote:
>
> On Wed, Aug 10, 2022 at 11:28:18AM -0400, Alex Deucher wrote:
> > On Tue, Jul 19, 2022 at 2:57 PM Alex Deucher <alexander.deucher at amd.com> wrote:
> > >
> > > The new vkms virtual display code is atomic so there is
> > > no need to call drm_helper_disable_unused_functions()
> > > when it is enabled.  Doing so can result in a segfault.
> > > When the driver switched from the old virtual display code
> > > to the new atomic virtual display code, it was missed that
> > > we enable virtual display unconditionally under SR-IOV
> > > so the checks here missed that case.  Add the missing
> > > check for SR-IOV.
> > >
> > > There is no equivalent of this patch for Linus' tree
> > > because the relevant code no longer exists.  This patch
> > > is only relevant to kernels 5.15 and 5.16.
> > >
> > > Fixes: 84ec374bd580 ("drm/amdgpu: create amdgpu_vkms (v4)")
> > > Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
> > > Cc: stable at vger.kernel.org # 5.15.x
> > > Cc: hgoffin at amazon.com
> >
> > Hi Greg,
> >
> > Is there any chance this can get applied?  It fixes a regression on
> > 5.15 and 5.16.
>
> Ah, missed this as it was not obvious that this was a not-upstream
> commit at all, sorry.
>
> I'll dig it out of lore.kernel.org and queue it up for the next round of
> releases, but note, this is our "busy time" with many patches marked for
> stable.
>
> Oh and 5.16 is long end-of-life, nothing anyone can do there, and no one
> should be using that kernel version anymore, so no issues there.

Thanks Greg.  Much appreciated.

Alex

>
> thanks,
>
> greg k-h