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@xxxxxxxxxxxxxxxxxx> > >>>>>> 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=linux-5.10.y&id=520d05a77b2866eb4cb9e548e1d8c8abcfe60ec5 > >>>> > >>>> 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...
