Am 29.08.2018 um 04:52 schrieb Zhang, Jerry (Junwei): > On 08/28/2018 08:40 PM, Emily Deng wrote: >> Fix the VMC page fault when the running sequence is as below: >> 1.amdgpu_gem_create_ioctl >> 2.ttm_bo_swapout->amdgpu_vm_bo_invalidate, as not called >> amdgpu_vm_bo_base_init, so won't called >> list_add_tail(&base->bo_list, &bo->va). Even the bo was evicted, >> it won't set the bo_base->moved. > > IMO, the evicted bo should be created previously. > On BO creation we will add it to the bo->va as below: > > amdgpu_gem_create_ioctl > Â drm_gem_handle_create > Â Â Â amdgpu_gem_object_open And here is the problem. Between creating the BO and opening it in the client the BO can be evicted. That's what Emily's patch is handling here. Christian. > amdgpu_vm_bo_add > Â Â Â Â Â Â Â amdgpu_vm_bo_base_init > Â Â Â Â Â Â Â Â Â list_add_tail(&base->bo_list, &bo->va) > > Then it could be set moved in bo invalidate when evicting. > > could you provide a bit more backgroud about the issue? > looks a per vm bo is evicted and a new same bo created. > > Jerry > >> 3.drm_gem_open_ioctl->amdgpu_vm_bo_base_init, here only called >> list_move_tail(&base->vm_status, &vm->evicted), but not set the >> bo_base->moved. >> 4.amdgpu_vm_bo_map->amdgpu_vm_bo_insert_map, as the bo_base->moved is >> not set true, the function amdgpu_vm_bo_insert_map will call >> list_move(&bo_va->base.vm_status, &vm->moved) >> 5.amdgpu_cs_ioctl won't validate the swapout bo, as it is only in the >> moved list, not in the evict list. So VMC page fault occurs. >> >> Signed-off-by: Emily Deng <Emily.Deng at amd.com> >> --- >> Â drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 1 + >> Â 1 file changed, 1 insertion(+) >> >> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c >> b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c >> index 1f4b8df..015e20e 100644 >> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c >> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c >> @@ -172,6 +172,7 @@ static void amdgpu_vm_bo_base_init(struct >> amdgpu_vm_bo_base *base, >> Â Â Â Â Â Â * is validated on next vm use to avoid fault. >> Â Â Â Â Â Â * */ >> Â Â Â Â Â list_move_tail(&base->vm_status, &vm->evicted); >> +Â Â Â base->moved = true; >> Â } >> >> Â /** >> > _______________________________________________ > amd-gfx mailing list > amd-gfx at lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/amd-gfx
