[RFC v2 11/13] sync_file: Protect access to driver and timeline name

[Tvrtko Ursulin]

Protect the access to driver and timeline name which otherwise could be
freed as dma-fence exported is signalling fences.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursu...@igalia.com>
---
 drivers/dma-buf/sync_file.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/dma-buf/sync_file.c b/drivers/dma-buf/sync_file.c
index 212df4b849fe..ad87116baa24 100644
--- a/drivers/dma-buf/sync_file.c
+++ b/drivers/dma-buf/sync_file.c
@@ -136,11 +136,13 @@ char *sync_file_get_name(struct sync_file *sync_file, 
char *buf, int len)
        } else {
                struct dma_fence *fence = sync_file->fence;
 
+               dma_fence_access_begin();
                snprintf(buf, len, "%s-%s%llu-%lld",
                         dma_fence_driver_name(fence),
                         dma_fence_timeline_name(fence),
                         fence->context,
                         fence->seqno);
+               dma_fence_access_end();
        }
 
        return buf;
@@ -262,6 +264,8 @@ static long sync_file_ioctl_merge(struct sync_file 
*sync_file,
 static int sync_fill_fence_info(struct dma_fence *fence,
                                 struct sync_fence_info *info)
 {
+       dma_fence_access_begin();
+
        strscpy(info->obj_name, dma_fence_timeline_name(fence),
                sizeof(info->obj_name));
        strscpy(info->driver_name, dma_fence_driver_name(fence),
@@ -273,6 +277,8 @@ static int sync_fill_fence_info(struct dma_fence *fence,
                        ktime_to_ns(dma_fence_timestamp(fence)) :
                        ktime_set(0, 0);
 
+       dma_fence_access_end();
+
        return info->status;
 }
 
-- 
2.48.0