drm/nouveau: fix race when adding delayed work items

kernel.org bz#198221.

Reported-by: Petr Vandrovec <petr@vandrovec.name>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

diff --git a/drivers/gpu/drm/nouveau/nouveau_drm.c b/drivers/gpu/drm/nouveau/nouveau_drm.c
index 8d4a5be..56fe261 100644 (file)
--- a/drivers/gpu/drm/nouveau/nouveau_drm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_drm.c
@@ -152,9 +152,9 @@ nouveau_cli_work_queue(struct nouveau_cli *cli, struct dma_fence *fence,
        work->cli = cli;
        mutex_lock(&cli->lock);
        list_add_tail(&work->head, &cli->worker);
-       mutex_unlock(&cli->lock);
        if (dma_fence_add_callback(fence, &work->cb, nouveau_cli_work_fence))
                nouveau_cli_work_fence(fence, &work->cb);
+       mutex_unlock(&cli->lock);
 }
 
 static void