Quoting Lionel Landwerlin (2018-05-11 15:28:24) > On 11/05/18 15:18, Chris Wilson wrote: > > Quoting Lionel Landwerlin (2018-05-11 15:14:13) > >> My understanding of the virtual memory addressing from the GPU is limited... > >> But how can the GPU poke at the kernel's allocated data? > >> I thought we mapped into the GPU's address space only what is allocated > >> through gem. > > Correct. The HW should only be accessing the pages through the GTT and > > the GTT should only contain known pages (or a pointer to the scratch > > page). There is maybe a hole where we are freeing the memory before > > the HW has finished using it (still writing through stale TLB and > > whatnot even though the system has reallocated the pages), but other > > than that quite, quite scary. Hence this awooga. > > > Oh right... > > So this patch is a backup if you previous one won't fix the issue we see > on CI? Yes. Try to fix, it we can't, we disable until we can. It may also be purely coincidental that we've seen this bug a few times around the same test only on this machine... ;) -Chris
