amdgpu_benchmark_do_move() can exit the loop early if
amdgpu_copy_buffer() or dma_fence_wait() fails.
In the error path, the function jumps to the exit label
without releasing adev->mman.default_entity.lock, which
leaves the mutex held and results in a lock imbalance.
This can block subsequent users of default_entity and
potentially cause deadlocks.
Move the mutex_unlock() to the common exit path so the
lock is released on both success and error returns.
This fixes:
drivers/gpu/drm/amd/amdgpu/amdgpu_benchmark.c:57 amdgpu_benchmark_do_move()
warn: inconsistent returns '&adev->mman.default_entity.lock'.
Fixes: 64c9e5ec16fa ("drm/amdgpu: add missing lock in amdgpu_benchmark_do_move")
Reported-by: Dan Carpenter <[email protected]>
Cc: Pierre-Eric Pelloux-Prayer <[email protected]>
Cc: Christian König <[email protected]>
Cc: Alex Deucher <[email protected]>
Signed-off-by: Srinivasan Shanmugam <[email protected]>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_benchmark.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_benchmark.c
b/drivers/gpu/drm/amd/amdgpu/amdgpu_benchmark.c
index 98ccd7ab9e9a..024d1fe36716 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_benchmark.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_benchmark.c
@@ -33,7 +33,7 @@ static int amdgpu_benchmark_do_move(struct amdgpu_device
*adev, unsigned size,
{
ktime_t stime, etime;
struct dma_fence *fence;
- int i, r;
+ int i, r = 0;
mutex_lock(&adev->mman.default_entity.lock);
stime = ktime_get();
@@ -48,9 +48,10 @@ static int amdgpu_benchmark_do_move(struct amdgpu_device
*adev, unsigned size,
if (r)
goto exit_do_move;
}
- mutex_unlock(&adev->mman.default_entity.lock);
+
exit_do_move:
+ mutex_unlock(&adev->mman.default_entity.lock);
etime = ktime_get();
*time_ms = ktime_ms_delta(etime, stime);
--
2.34.1
