On Tue, Mar 29, 2022 at 10:48:10AM +0200, Daniel Vetter wrote:
On Tue, Mar 29, 2022 at 09:00:01AM +0200, Christian König wrote:
A bug inside the new sync-file merge code created empty dma_fence_array instances.
Warn about that and handle those without crashing.
Signed-off-by: Christian König christian.koenig@amd.com
drivers/dma-buf/dma-fence-array.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/drivers/dma-buf/dma-fence-array.c b/drivers/dma-buf/dma-fence-array.c index 52b85d292383..5c8a7084577b 100644 --- a/drivers/dma-buf/dma-fence-array.c +++ b/drivers/dma-buf/dma-fence-array.c @@ -159,6 +159,8 @@ struct dma_fence_array *dma_fence_array_create(int num_fences, struct dma_fence_array *array; size_t size = sizeof(*array);
- WARN_ON(!num_fences || !fences);
WARN_ON and then dying randomly is kinda not nice, I'd wrap this in an
if (WARN_ON) return NULL;
with that: Reviewed-by: Daniel Vetter daniel.vetter@ffwll.ch
Uh strike that, you handle it gracefully with the check below.
- /* Allocate the callback structures behind the array. */ size += num_fences * sizeof(struct dma_fence_array_cb); array = kzalloc(size, GFP_KERNEL);
@@ -231,6 +233,9 @@ struct dma_fence *dma_fence_array_first(struct dma_fence *head) if (!array) return head;
Maybe add a comment here that this is just defensive programming, like
/* No fences isn't allowed and splats in create, but be defensive */
Either way Reviewed-by: Daniel Vetter daniel.vetter@ffwll.ch I guess, coffee not quite yet working. -Daniel
- if (!array->num_fences)
return NULL;- return array->fences[0];
} EXPORT_SYMBOL(dma_fence_array_first); -- 2.25.1
-- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch