From: Christian König <christian.koenig@xxxxxxx> reservation_object_wait_timeout_rcu() should enable signaling even with a zero timeout, but ttm_bo_wait() can also be called from atomic context and then it is not a good idea to do this. Reviewed-by: Alex Deucher <alexander.deucher at amd.com> Signed-off-by: Christian König <christian.koenig at amd.com> Signed-off-by: Alex Deucher <alexander.deucher at amd.com> --- drivers/gpu/drm/ttm/ttm_bo.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c index f6ff579..d506361 100644 --- a/drivers/gpu/drm/ttm/ttm_bo.c +++ b/drivers/gpu/drm/ttm/ttm_bo.c @@ -1611,7 +1611,14 @@ EXPORT_SYMBOL(ttm_bo_unmap_virtual); int ttm_bo_wait(struct ttm_buffer_object *bo, bool interruptible, bool no_wait) { - long timeout = no_wait ? 0 : 15 * HZ; + long timeout = 15 * HZ; + + if (no_wait) { + if (reservation_object_test_signaled_rcu(bo->resv, true)) + return 0; + else + return -EBUSY; + } timeout = reservation_object_wait_timeout_rcu(bo->resv, true, interruptible, timeout); -- 2.5.5