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author | Christian König | 2019-03-29 19:30:23 +0100 |
---|---|---|
committer | Greg Kroah-Hartman | 2019-05-31 15:46:23 +0200 |
commit | d8a36f8418034bacef0b5b73c0822f41646d77ba (patch) | |
tree | 0418c22d4884e4285f0406e3aee6ed9a4c539ce6 /drivers/gpu/drm/amd | |
parent | mmc: sdhci-of-esdhc: add erratum eSDHC-A001 and A-008358 support (diff) | |
download | kernel-qcow2-linux-d8a36f8418034bacef0b5b73c0822f41646d77ba.tar.gz kernel-qcow2-linux-d8a36f8418034bacef0b5b73c0822f41646d77ba.tar.xz kernel-qcow2-linux-d8a36f8418034bacef0b5b73c0822f41646d77ba.zip |
drm/amdgpu: fix old fence check in amdgpu_fence_emit
[ Upstream commit 3d2aca8c8620346abdba96c6300d2c0b90a1d0cc ]
We don't hold a reference to the old fence, so it can go away
any time we are waiting for it to signal.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Chunming Zhou <david1.zhou@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/gpu/drm/amd')
-rw-r--r-- | drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c | 24 |
1 files changed, 17 insertions, 7 deletions
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c index 7056925eb386..869ff624b108 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c @@ -136,8 +136,9 @@ int amdgpu_fence_emit(struct amdgpu_ring *ring, struct dma_fence **f, { struct amdgpu_device *adev = ring->adev; struct amdgpu_fence *fence; - struct dma_fence *old, **ptr; + struct dma_fence __rcu **ptr; uint32_t seq; + int r; fence = kmem_cache_alloc(amdgpu_fence_slab, GFP_KERNEL); if (fence == NULL) @@ -153,15 +154,24 @@ int amdgpu_fence_emit(struct amdgpu_ring *ring, struct dma_fence **f, seq, flags | AMDGPU_FENCE_FLAG_INT); ptr = &ring->fence_drv.fences[seq & ring->fence_drv.num_fences_mask]; + if (unlikely(rcu_dereference_protected(*ptr, 1))) { + struct dma_fence *old; + + rcu_read_lock(); + old = dma_fence_get_rcu_safe(ptr); + rcu_read_unlock(); + + if (old) { + r = dma_fence_wait(old, false); + dma_fence_put(old); + if (r) + return r; + } + } + /* This function can't be called concurrently anyway, otherwise * emitting the fence would mess up the hardware ring buffer. */ - old = rcu_dereference_protected(*ptr, 1); - if (old && !dma_fence_is_signaled(old)) { - DRM_INFO("rcu slot is busy\n"); - dma_fence_wait(old, false); - } - rcu_assign_pointer(*ptr, dma_fence_get(&fence->base)); *f = &fence->base; |