Merge tag 'vfio-v5.3-rc1' of git://github.com/awilliam/linux-vfio

[linux-2.6-microblaze.git] / drivers / dma-buf / dma-fence.c

diff --git a/drivers/dma-buf/dma-fence.c b/drivers/dma-buf/dma-fence.c
index 227a194..59ac96e 100644 (file)
--- a/drivers/dma-buf/dma-fence.c
+++ b/drivers/dma-buf/dma-fence.c
@@ -248,8 +248,25 @@ void dma_fence_release(struct kref *kref)
 
        trace_dma_fence_destroy(fence);
 
-       /* Failed to signal before release, could be a refcounting issue */
-       WARN_ON(!list_empty(&fence->cb_list));
+       if (WARN(!list_empty(&fence->cb_list),
+                "Fence %s:%s:%llx:%llx released with pending signals!\n",
+                fence->ops->get_driver_name(fence),
+                fence->ops->get_timeline_name(fence),
+                fence->context, fence->seqno)) {
+               unsigned long flags;
+
+               /*
+                * Failed to signal before release, likely a refcounting issue.
+                *
+                * This should never happen, but if it does make sure that we
+                * don't leave chains dangling. We set the error flag first
+                * so that the callbacks know this signal is due to an error.
+                */
+               spin_lock_irqsave(fence->lock, flags);
+               fence->error = -EDEADLK;
+               dma_fence_signal_locked(fence);
+               spin_unlock_irqrestore(fence->lock, flags);
+       }
 
        if (fence->ops->release)
                fence->ops->release(fence);