| Message ID | 20220727230755.1445806-1-Felix.Kuehling@amd.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/amdgpu: Fix stub fence refcount underflow | expand |
Am 2022-07-27 um 23:52 schrieb Alex Deucher: > On Wed, Jul 27, 2022 at 7:08 PM Felix Kuehling <Felix.Kuehling@amd.com> wrote: >> Don't drop the stub fence reference after installing it as a replacement >> for the eviction fence. dma_resv_replace_fences doesn't take another >> reference to the fence, so it takes ownership of the reference passed >> in by us. >> >> Fixes: 548e7432dc2d ("dma-buf: add dma_resv_replace_fences v2") >> CC: Christian König <christian.koenig@amd.com> >> Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com> > Acked-by: Alex Deucher <alexander.deucher@amd.com> This patch is the wrong solution. Xinhui added a dma_fence_get in dma_resv_replace_fences in his patch "dma-buf: Fix one use-after-free of fence". So this patch is not needed any more. Regards, Felix >> --- >> drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c | 1 - >> 1 file changed, 1 deletion(-) >> >> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c >> index 87a3a3ae9448..a6c7dcd8c345 100644 >> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c >> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c >> @@ -294,7 +294,6 @@ static int amdgpu_amdkfd_remove_eviction_fence(struct amdgpu_bo *bo, >> replacement = dma_fence_get_stub(); >> dma_resv_replace_fences(bo->tbo.base.resv, ef->base.context, >> replacement, DMA_RESV_USAGE_READ); >> - dma_fence_put(replacement); >> return 0; >> } >> >> -- >> 2.32.0 >>
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c index 87a3a3ae9448..a6c7dcd8c345 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c @@ -294,7 +294,6 @@ static int amdgpu_amdkfd_remove_eviction_fence(struct amdgpu_bo *bo, replacement = dma_fence_get_stub(); dma_resv_replace_fences(bo->tbo.base.resv, ef->base.context, replacement, DMA_RESV_USAGE_READ); - dma_fence_put(replacement); return 0; }
Don't drop the stub fence reference after installing it as a replacement for the eviction fence. dma_resv_replace_fences doesn't take another reference to the fence, so it takes ownership of the reference passed in by us. Fixes: 548e7432dc2d ("dma-buf: add dma_resv_replace_fences v2") CC: Christian König <christian.koenig@amd.com> Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com> --- drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c | 1 - 1 file changed, 1 deletion(-)