Quoting Hans de Goede (2021-02-10 10:37:19)
Hi,
On 2/10/21 12:07 AM, Chris Wilson wrote:
Quoting Hans de Goede (2021-02-09 11:46:46)
Hi,
On 2/9/21 12:27 AM, Chris Wilson wrote:
Quoting Hans de Goede (2021-02-08 20:38:58)
Hi All,
We (Fedora) have been receiving reports from multiple users about gfx issues / glitches stating with 5.10.9. All reporters are users of Ivy Bridge / Haswell iGPUs and all reporters report that adding i915.mitigations=off to the cmdline fixes things, see:
I tried to reproduce this on the w/e on hsw-gt1, to no avail; and piglit did not report any differences with and without mitigations. I have yet to test other platforms. So I don't yet have an alternative.
Note the original / first reporter of:
https://bugzilla.redhat.com/show_bug.cgi?id=1925346
Is using hsw-gt2, so it seems that the problem is not just the enabling of the mitigations on ivy-bridge / bay-trail but that there actually is a regression on devices where the WA worked fine before...
There have been 3 crashes uploaded related to v5.10.9, and in all 3 cases the ACTHD has been in the first page. This strongly suggests that the w/a is scribbling over address 0. And there's then a very good chance that
commit 29d35b73ead4e41aa0d1a954c9bfbdce659ec5d6 Author: Chris Wilson chris@chris-wilson.co.uk Date: Mon Jan 25 12:50:33 2021 +0000
drm/i915/gt: Always try to reserve GGTT address 0x0commit 489140b5ba2e7cc4b853c29e0591895ddb462a82 upstream.
in v5.10.14 is sufficient to hide the issue.
That one actually is already in v5.10.13 and the various reportes of these issues have already tested 5.10.13. They did mention that it took longer to reproduce with 5.10.13 then with 5.10.10, but that could also be due to:
"drm/i915/gt: Clear CACHE_MODE prior to clearing residuals" https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=l...
There's also another pair of pipecontrols required for that:
d30bbd62b1bf ("drm/i915/gt: Flush before changing register state")
which didn't get picked up for stable.
https://intel-gfx-ci.01.org/tree/linux-stable/index-alt.html?
shows that we are still missing a couple of fixes for the w/a, at least compare to BAT on drm-tip. -Chris