El lun, 28-04-2025 a las 10:13 +0200, Boris Brezillon escribió: > Hi Iago, > > On Mon, 28 Apr 2025 08:55:07 +0200 > Iago Toral <ito...@igalia.com> wrote: (...) > > As I described above, v3d is not quite an allocation-on-fault > > mechanism > > but rather, we get a dedicated interrupt from the hw when it needs > > more > > memory, which I believe happens a bit before it completely runs out > > of > > memory actually. Maybe that changes the picture since we don't > > exactly > > use a fault handler? > > Not really. Any mechanism relying on on-demand allocation in the > dma_fence signalling path is problematic. The fact it's based on a > fault handler might add extra problems on top, but both designs > violate > the dma_fence contract stating that no non-fallible allocation should > be done in the dma_fence signalling path (that is, any allocation > happening between the moment the job was queued to the > drm_sched_entity, and the moment the job fence is signalled). > > Given, the description you made, I think we can add v3d to the list > of > problematic drivers :-(.
In that case we should add vc4 as well, since it is the same story there. Thanks, Iago
