5.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Nikita Zhandarovich <n.zhandarovich@xxxxxxxxxx>
[ Upstream commit 71225e1c930942cb1e042fc08c5cc0c4ef30e95e ]
In the unlikely event of radeon_ring_lock() failing, its errno return
value should be processed. This patch checks said return value and
prints a debug message in case of an error.
Found by Linux Verification Center (linuxtesting.org) with static
analysis tool SVACE.
Fixes: 48c0c902e2e6 ("drm/radeon/kms: add support for CP setup on SI")
Signed-off-by: Nikita Zhandarovich <n.zhandarovich@xxxxxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/gpu/drm/radeon/si.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/drivers/gpu/drm/radeon/si.c b/drivers/gpu/drm/radeon/si.c
index 74cbed9377f0..ae74e8b01ee0 100644
--- a/drivers/gpu/drm/radeon/si.c
+++ b/drivers/gpu/drm/radeon/si.c
@@ -3616,6 +3616,10 @@ static int si_cp_start(struct radeon_device *rdev)
for (i = RADEON_RING_TYPE_GFX_INDEX; i <= CAYMAN_RING_TYPE_CP2_INDEX; ++i) {
ring = &rdev->ring[i];
r = radeon_ring_lock(rdev, ring, 2);
+ if (r) {
+ DRM_ERROR("radeon: cp failed to lock ring (%d).\n", r);
+ return r;
+ }
/* clear the compute context state */
radeon_ring_write(ring, PACKET3_COMPUTE(PACKET3_CLEAR_STATE, 0));
--
2.43.0
