drm/radeon: hold reference to fences in radeon_sa_bo_new

commit f6ff4f67cdf8455d0a4226eeeaf5af17c37d05eb upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/gpu/drm/radeon/radeon_sa.c b/drivers/gpu/drm/radeon/radeon_sa.c
index f0bac68254b79a5dd31cfdc14ce80a98bca91065..bb166849aa6e876e012eaabb801a512945cb4424 100644 (file)
--- 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 && block) {