drm/radeon: hold reference to fences in radeon_sa_bo_new

An arbitrary amount of time can pass between spin_unlock and
radeon_fence_wait_any, so we need to ensure that nobody frees the
fences from under us.

Based on the analogous fix for amdgpu.

Signed-off-by: Nicolai Hähnle <nicolai.haehnle@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Cc: stable@vger.kernel.org

1 files changed, 5 insertions, 0 deletions

diff --git a/drivers/gpu/drm/radeon/radeon_sa.c b/drivers/gpu/drm/radeon/radeon_sa.c
index c507896aca45..197b157b73d0 100644
--- a/drivers/gpu/drm/radeon/radeon_sa.c
+++ b/drivers/gpu/drm/radeon/radeon_sa.c
@@ -349,8 +349,13 @@ int radeon_sa_bo_new(struct radeon_device *rdev,
                         /* see if we can skip over some allocations */
                 } while (radeon_sa_bo_next_hole(sa_manager, fences, tries));
 
+                for (i = 0; i < RADEON_NUM_RINGS; ++i)
+                        radeon_fence_ref(fences[i]);
+
                 spin_unlock(&sa_manager->wq.lock);
                 r = radeon_fence_wait_any(rdev, fences, false);
+                for (i = 0; i < RADEON_NUM_RINGS; ++i)
+                        radeon_fence_unref(&fences[i]);
                 spin_lock(&sa_manager->wq.lock);
                 /* if we have nothing to wait for block */
                 if (r == -ENOENT) {