[PATCH 2/2] drm/amdkfd: Clear MODE.VSKIP in gfx9 trap handler

[Jay Cornwall]

On 1/10/2025 12:14, Six, Lancelot wrote:

>> If user shader issues S_SETVSKIP then this state will persist when
>> executing the trap handler, causing vector instructions to be
>> skipped.
>>
>> Restore VSKIP state before resuming the user shader.
> 
> Hi,
> 
> I agree with the patch, I just find the text above confusing.
> 
> Reading this, I'd expect to see vskip to be resumed before s_rfe in the "non-save"
> path.  However, that patch touches the save path (disable vskip as soon as MODE
> has been saved) so the rest of the save procedure can work as expected.  VSKIP
> will eventually be restored in the restore path when restoring MODE (no change
> needed), which is done after any instruction that could have been impacted by
> VSKIP has already been executed.

How about:

VSKIP state is already saved/restored through the MODE register.