On Thu, Jan 30, 2025 at 10:28:00AM +0100, David Hildenbrand wrote: > On 30.01.25 06:34, Alistair Popple wrote: > > Looking at hmm_test I see that doesn't use the sequence counter to ensure > > the PTE remains valid whilst it is mapped. I think that is probably wrong, so > > apologies if that lead you astray. > > Yes, the hmm_test does not completely follow the same model the nouveau > implementation does; so it might not be completely correct. But unrelated but just crossed my mind: I guess another crucial difference is that the hw (probably, not sure) will restart the fault if we don't repair it to its liking. So the hmm-test does need some kind of retry loop too somewhere to match that. But might be good to also still land some of the other improvements discussed in these threads to make make_device_exclusive a bit more reliable instead of relying on busy-looping throug the hw fault handler for everything. -Sima -- Simona Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch
