Re: [PATCH 6/7] drm/i915: Evade the vblank on the scanline of the joiner primary

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential
issue to consider:
- [High] drm/i915: Signed-off-by trailer uses handle instead of real
  name
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commit 516746727da5577decb0038cc22a5dddd9cbc589
Author: ElXreno <elxreno@gmail.com>

> drm/i915: Evade the vblank on the scanline of the joiner primary
>
> The scanline counter of a joiner secondary pipe was observed to wrap
> at 8192 lines on Arrow Lake, with pipes A and B joined. Sampling
> PIPEDSL of both pipes, they agree up to line 8191, which is the
> largest value pipe B ever returns, while pipe A counts on up to the
> vmax vtotal. From line 8192 on pipe B reads 8192 lines less than
> pipe A. This comes from measurement only, I have no documentation for
> it, and I could not check whether it is a property of the joiner
> secondary or of that pipe.
>
> It is harmless as long as vtotal stays below 8192, which every fixed
> refresh rate mode that needs the joiner does. With VRR the vmax
> vtotal can be larger, 12200 for a 3840x2400@240 mode with a 48 Hz
> lower limit. The vmax vblank start at line 12160 then reads as 3968
> on the secondary, vblank evasion on that pipe never sees its evasion
> window, and the pipe gets armed across the vblank:
>
>  Atomic update failure on pipe B (start=48480 end=48481) time 8 us, min 12101, max 12159, scanline start 3965, end 3969
>
> All joined pipes run off the timings of the primary, so look at the
> scanline counter of the primary when evading the vblank on a
> secondary. This matters for the commits that still take the per pipe
> critical sections with the joiner.
>
> Only the evasion is changed. The vblank timestamps of a secondary
> still come from its own counter, and so does the end scanline in the
> message above, while the start scanline is now the primary's.
>
> Signed-off-by: ElXreno <elxreno@gmail.com>

[Severity: High]
Documentation/process/submitting-patches.rst requires a real name in the
Signed-off-by trailer and does not permit handles or pseudonyms. Could
this be updated to use a full real name in both the Author header and
Signed-off-by line?

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Sashiko AI review · https://sashiko.dev/#/patchset/20261114014335.2132756-1-elxreno@gmail.com?part=6