dma-buf: add WARN_ON() illegal dma-fence signaling

Calling the signaling a NULL fence is obviously a coding error in a
driver. Those functions unfortunately just returned silently without
raising a warning.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Simona Vetter <simona.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20240911085903.1496-2-christian.koenig@amd.com

diff --git a/drivers/dma-buf/dma-fence.c b/drivers/dma-buf/dma-fence.c
index f8303ae..f0cdd3e 100644 (file)
--- a/drivers/dma-buf/dma-fence.c
+++ b/drivers/dma-buf/dma-fence.c
@@ -412,7 +412,7 @@ int dma_fence_signal_timestamp(struct dma_fence *fence, ktime_t timestamp)
        unsigned long flags;
        int ret;
 
-       if (!fence)
+       if (WARN_ON(!fence))
                return -EINVAL;
 
        spin_lock_irqsave(fence->lock, flags);
@@ -464,7 +464,7 @@ int dma_fence_signal(struct dma_fence *fence)
        int ret;
        bool tmp;
 
-       if (!fence)
+       if (WARN_ON(!fence))
                return -EINVAL;
 
        tmp = dma_fence_begin_signalling();