On Thu, 3 Nov 2022 at 00:14, Brian Norris <briannorris@xxxxxxxxxxxx> wrote: > > On Wed, Nov 02, 2022 at 12:18:37PM +0000, Matthew Auld wrote: > > On Tue, 1 Nov 2022 at 21:58, Brian Norris <briannorris@xxxxxxxxxxxx> wrote: > > > > > > On Fri, Oct 28, 2022 at 5:24 PM Patchwork > > > <patchwork@xxxxxxxxxxxxxxxxxxxxxx> wrote: > > > > > > > > Patch Details > > > > Series:drm/i915: Set PROBE_PREFER_ASYNCHRONOUS > > > > URL:https://patchwork.freedesktop.org/series/110277/ > > > > State:failure > > > > Details:https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_110277v1/index.html > > > > > > > > CI Bug Log - changes from CI_DRM_12317 -> Patchwork_110277v1 > > > > > > > > Summary > > > > > > > > FAILURE > > > > > > > > Serious unknown changes coming with Patchwork_110277v1 absolutely need to be > > > > verified manually. > > > > > > > > If you think the reported changes have nothing to do with the changes > > > > introduced in Patchwork_110277v1, please notify your bug team to allow them > > > > to document this new failure mode, which will reduce false positives in CI. > > > > > > > > External URL: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_110277v1/index.html > > > > > > For the record, I have almost zero idea what to do with this. From > > > what I can tell, most (all?) of these failures are flaky(?) already > > > and are probably not related to my change. > > > > https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_110277v1/index.html > > > > According to that link, this change appears to break every platform > > when running the live selftests (looking at the purple squares). > > Running the selftests normally involves loading and unloading the > > module. Looking at the logs there is scary stuff like: > > > [...] > > Ah, thanks. I'm not sure what made me think the tests were failing the > same way on drm-tip, but maybe just chalk that up to my unfamiliarity > with this particular dashboard... (There are a few isolated failure > and/or flakes on drm-tip, but they don't look like this.) > > Anyway, I think I managed to run some of these tests on my own platforms > [1], and I don't reproduce those failures. I do see other failures > (crashes) though, like in i915_gem_mman_live_selftests/igt_mmap, where > igt_mmap_offset() (selftest-only code) -> vm_mmap() assumes we have a > valid |current->mm|. But that's borrowing the modprobe process's memory > map, and with async probe, the selftest sequence happens in a kernel > worker instead (and current->mm is NULL). So that clearly won't work. Semi related: https://lore.kernel.org/intel-gfx/20221104134703.3770b371@maurocar-mobl2/T/#m888972bb1ffb0a913e3db8b4099dffdc2ec7a0dc Sounds like a similar issue when trying to convert the live selftests over to kunit. > > I suppose I could disable async probe when built as a module (I believe > it doesn't really have any value, since the module load task just waits > for the async task anyway). I'm not familiar enough with MM to know what > the vm_mmap() alternatives are, but this particular bit of code does > feel odd. > > Additionally, I think this implies that live_selftests will break if > i915 is built-in (i.e., =y, not =m), as we'll again run in a > kernel-thread context at boot time. But I would hope nobody is trying to > run them that way? I guess this gets even hairier, because even if the > driver is built into the kernel, it's possible to kick them off from a > process context by tweaking the module parameters later, and then > re-binding the device... So all in all, this bug leaves an ugly > situation, with or without my patch. > > I'm still curious about the reported failures, but maybe they require > some particular sequence of tests? I also don't have the full > igt-gpu-tools set running, so maybe they do something a little > differently than my steps in [1]? > > Brian > > [1] I have a GLk system, if it matters. I figured I can run some of > these with any one of the following: > > modprobe i915 live_selftests=1 > modprobe i915 live_selftests=1 igt__20__live_workarounds=Y > modprobe i915 live_selftests=1 igt__19__live_uncore=Y > modprobe i915 live_selftests=1 igt__18__live_sanitycheck=Y > ...
