On 2/25/26 14:37, Michel Dänzer wrote: > On 2/25/26 14:25, Christian König wrote: >> On 2/25/26 13:46, Yicong Hui wrote: >>> This patch series adds 2 new flags, DRM_SYNCOBJ_QUERY_FLAGS_ERROR and >>> DRM_SYNCOBJ_WAIT_FLAGS_ABORT_ON_ERROR for 3 ioctl operations >>> DRM_IOCTL_SYNCOBJ_QUERY, DRM_IOCTL_SYNCOBJ_WAIT and >>> DRM_IOCTL_SYNCOBJ_TIMELINE_WAIT to allow them to batch-request error >>> codes from multiple syncobjs and abort early upon error of any of them. >> >> Patch #1 looks good enough to add my rb. >> >> Patch #2 looks good as well, but I'm not familiar enough with the code and >> have no time to wrap my head around it to give a review. >> >> Adding a few people on CC, maybe somebody has time to take another look. >> >>> >>> Based on discussions from Michel Dänzer and Christian König, and a >>> starter task from the DRM todo documentation. >>> >>> See https://gitlab.gnome.org/GNOME/mutter/-/issues/4624 for discussions >>> on userspace implementation. >>> >>> I have looked into adding sub test cases into syncobj_wait.c and >>> syncobj_timeline.c, igt-tests for this and I think I understand the >>> process for writing tests and submitting them, however, these ioctls >>> only trigger in the case that there is an error, but I am not sure what >>> is the best way to artifically trigger an error from userspace in order >>> to test that these ioctl flags work. What's the recommended way to >>> approach this? >> >> When Michel agrees that this is the way to go then we either need an >> in-kernel selftest (see directory drivers/gpu/drm/tests/) or an userspace >> IGT test. >> >> Not sure what is more appropriate, maybe somebody on CC has more experience >> with that. > > I'd advise against landing this in the kernel before there's a corresponding > display server implementation making use of it, in a mergeable state.
Yeah we clearly have the rule that this can't be pushed into the kernel without userspace code as well. > Otherwise you might end up with the kernel having to support UAPI which no > real-world user space actually uses. Been there, done that myself. > > > I don't have the capacity to contribute anything more than advice at this > point. Oh that is sad. Do you know anybody who could work on that? It is a clear improvement to error handling and I don't like to keep Yicong's work only on the mailing list. Thanks, Christian.
