4.19-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 644ddd8d65ad..167dbcef0c38 100644 --- a/drivers/gpu/drm/radeon/si.c +++ b/drivers/gpu/drm/radeon/si.c @@ -3612,6 +3612,10 @@ 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