CVE-2026-43477
Gravedad:
Pendiente de análisis
Tipo:
No Disponible / Otro tipo
Fecha de publicación:
13/05/2026
Última modificación:
13/05/2026
Descripción
*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br />
<br />
drm/i915/vrr: Configure VRR timings after enabling TRANS_DDI_FUNC_CTL<br />
<br />
Apparently ICL may hang with an MCE if we write TRANS_VRR_VMAX/FLIPLINE<br />
before enabling TRANS_DDI_FUNC_CTL.<br />
<br />
Personally I was only able to reproduce a hang (on an Dell XPS 7390<br />
2-in-1) with an external display connected via a dock using a dodgy<br />
type-C cable that made the link training fail. After the failed<br />
link training the machine would hang. TGL seemed immune to the<br />
problem for whatever reason.<br />
<br />
BSpec does tell us to configure VRR after enabling TRANS_DDI_FUNC_CTL<br />
as well. The DMC firmware also does the VRR restore in two stages:<br />
- first stage seems to be unconditional and includes TRANS_VRR_CTL<br />
and a few other VRR registers, among other things<br />
- second stage is conditional on the DDI being enabled,<br />
and includes TRANS_DDI_FUNC_CTL and TRANS_VRR_VMAX/VMIN/FLIPLINE,<br />
among other things<br />
<br />
So let&#39;s reorder the steps to match to avoid the hang, and<br />
toss in an extra WARN to make sure we don&#39;t screw this up later.<br />
<br />
BSpec: 22243<br />
(cherry picked from commit 93f3a267c3dd4d811b224bb9e179a10d81456a74)



