On Sun, Feb 14, 2021 at 05:00:44PM +0100, Hans de Goede wrote:
Hi,
On 2/11/21 1:26 PM, Hans de Goede wrote:
Hi,
On 2/11/21 11:49 AM, Chris Wilson wrote:
Quoting Hans de Goede (2021-02-11 10:36:13)
Hi,
On 2/10/21 1:48 PM, Chris Wilson wrote:
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 0x0 > > commit 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...
Started looking for scratch page overwrites, and found this little gem: https://patchwork.freedesktop.org/patch/420436/?series=86947&rev=1
Looks promising wrt the cause of overwriting random addresses -- and I hope that is the explanation for the glitches/hangs. I have a hsw gt2 with gnome shell, piglit is happy, but I suspect it is all due to placement and so will only occur at random.
If you can give me a list of commits to cherry-pick then I can prepare a Fedora 5.10.y kernel which those added for the group of Fedora users who are hitting this to test.
e627d5923cae ("drm/i915/gt: One more flush for Baytrail clear residuals") d30bbd62b1bf ("drm/i915/gt: Flush before changing register state") 1914911f4aa0 ("drm/i915/gt: Correct surface base address for renderclear")
Thanks, the test-kernel is building now. I will let you know when I have heard back from the Fedora users (this will likely take 1-2 days).
I've heard back from 2 of the reporters who were seeing issues with 5.10.9+
And I'm happy to report 5.10.15 + the 3 commits mentioned above cherry-picked on top fixes the graphics glitches for them.
So if we can get these 3 commits into 5.10.y and 5.11.y then this should be resolved.
Great!
Hopefully these will show up in Linus's tree soon...