Hi Leo,

I am not sure - I have only personally tested the latest
Ubuntu kernel based on 7.0.0 (7.0.0-27.27). Could you link me to the
relevant commits / mailing list entries? I can read through them and
will try to give it a test soon if I have time.

-Mitchell Augustin



On Fri, Aug 7, 2026 at 9:59 AM Leo Li <[email protected]> wrote:
>
>
>
> On 2026-08-06 10:34, [email protected] wrote:
> > [Some people who received this message don't often get email from 
> > [email protected]. Learn why this is important at 
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> >
> > From: Mitchell Augustin <[email protected]>
> >
> > Issue: https://gitlab.freedesktop.org/drm/amd/-/work_items/5394
> > Ubuntu BugLink: https://bugs.launchpad.net/bugs/2162904
> >
> > This commit disables panel self-refresh when more than one display is
> > active to eliminate a common hang and system crash that happens
> > frequently on some laptops, evidently due to race conditions between
> > the DMCUB, amdgpu module, and possibly other components which are
> > exacerbated when more than one display is active.
> >
> > To my knowledge, a fix for the underlying failure condition is not
> > available upstream, so given how disruptive this is for impacted users,
> > I propose disabling this feature under this condition until it is fixed.
> > The main downside of disabling PSR is that it
> > will increase power consumption, but this should be barely noticeable to
> > end users, since PSR will remain enabled on laptops unconnected to
> > external monitors, and since laptops connected to external monitors are
> > likely typically also connected to power (and thus less concerned with
> > the energy savings afforded by PSR).
> >
> > Signed-off-by: Mitchell Augustin <[email protected]>
> >
>
> Hi Mitchell,
>
> Do you know if this issue still occurs on 7.2-rc6? It includes a bunch of 
> fixes targeting flip-done timeout issues that involved PSR.
>
> Thanks,
> Leo
>
> > ---
> >  drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c | 3 ++-
> >  1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c 
> > b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c
> > index 5d2715f78314..272f195b8c28 100644
> > --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c
> > +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c
> > @@ -152,7 +152,8 @@ void amdgpu_dm_crtc_set_panel_sr_feature(
> >                 struct amdgpu_dm_connector *aconn =
> >                         (struct amdgpu_dm_connector *) 
> > stream->dm_stream_context;
> >
> > -               if (!aconn->disallow_edp_enter_psr) {
> > +               /* Do not enter PSR if multiple displays are active to 
> > prevent DMCUB hangs */
> > +               if (!aconn->disallow_edp_enter_psr && 
> > dm->dc->current_state->stream_count == 1) {
> >                         amdgpu_dm_psr_enable(stream);
> >                         if (dm->idle_workqueue &&
> >                             (dm->dc->config.disable_ips == DMUB_IPS_ENABLE) 
> > &&
> > --
> > 2.43.0
> >
>


--
Mitchell Augustin
Software Engineer / Tech Lead - Ubuntu on NVIDIA DGX
Email:[email protected]
[email protected]
Location:United States of America (Central Time)


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