@@ -99,6 +99,12 @@ int dma_fence_chain_find_seqno(struct dma_fence **pfence, uint64_t seqno)
return -EINVAL;
dma_fence_chain_for_each(*pfence, &chain->base) {
+ if ((*pfence)->seqno < seqno) { /* already signaled */
+ dma_fence_put(*pfence);
+ *pfence = NULL;
+ break;
+ }
+
if ((*pfence)->context != chain->base.context ||
to_dma_fence_chain(*pfence)->prev_seqno < seqno)
break;
@@ -222,6 +228,7 @@ EXPORT_SYMBOL(dma_fence_chain_ops);
* @chain: the chain node to initialize
* @prev: the previous fence
* @fence: the current fence
+ * @seqno: the sequence number (syncpt) of the fence within the chain
*
* Initialize a new chain node and either start a new chain or add the node to
* the existing chain of the previous fence.
Whenever we walk along the dma-fence-chain, we prune signaled links to keep the chain nice and tidy. This leads to situations where we can prune a link and report the earlier fence as the target seqno -- violating our own consistency checks that the seqno is not more advanced than the last element in a dma-fence-chain. Report a NULL fence and success if the seqno has already been signaled. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> --- drivers/dma-buf/dma-fence-chain.c | 7 +++++++ 1 file changed, 7 insertions(+)