dma-fence: Silence sparse warning in dma_fence_describe

Sparse complains about assigning a string to a __rcu annotated local
variable:

drivers/dma-buf/dma-fence.c:1040:38: warning: incorrect type in initializer (different address spaces)
drivers/dma-buf/dma-fence.c:1040:38:    expected char const [noderef] __rcu *timeline
drivers/dma-buf/dma-fence.c:1040:38:    got char *
drivers/dma-buf/dma-fence.c:1041:36: warning: incorrect type in initializer (different address spaces)
drivers/dma-buf/dma-fence.c:1041:36:    expected char const [noderef] __rcu *driver
drivers/dma-buf/dma-fence.c:1041:36:    got char *

It is harmless but lets silence it.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@igalia.com>
Fixes: ac364014fd81 ("dma-buf: cleanup dma_fence_describe v3")
Cc: Christian König <christian.koenig@amd.com>
Cc: linux-media@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: linaro-mm-sig@lists.linaro.org
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Tvrtko Ursulin <tursulin@ursulin.net>
Link: https://lore.kernel.org/r/20260415083207.40513-1-tvrtko.ursulin@igalia.com

diff --git a/drivers/dma-buf/dma-fence.c b/drivers/dma-buf/dma-fence.c
index 35afcfcac5910ee98dc529ef77cf9aa64c9f7700..4dbbc9873ee3ef252b59c26a3668dcc02e0ebce7 100644 (file)
--- a/drivers/dma-buf/dma-fence.c
+++ b/drivers/dma-buf/dma-fence.c
@@ -1021,8 +1021,8 @@ EXPORT_SYMBOL(dma_fence_set_deadline);
  */
 void dma_fence_describe(struct dma_fence *fence, struct seq_file *seq)
 {
-       const char __rcu *timeline = "";
-       const char __rcu *driver = "";
+       const char __rcu *timeline = (const char __rcu *)"";
+       const char __rcu *driver = (const char __rcu *)"";
        const char *signaled = "";
 
        rcu_read_lock();