gpu: nvgpu: Fix semaphore refcounting

This patch fixes a refcounting issue in semaphore handling.

Change-Id: I03327c60ed6923a90663f0b845566e81af4b94d4
Signed-off-by: Arto Merilainen <amerilainen@nvidia.com>
Reviewed-on: http://git-master/r/453056
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/channel_sync_gk20a.c b/drivers/gpu/nvgpu/gk20a/channel_sync_gk20a.c
index 4d366fa9..ef9e3a37 100644
--- a/drivers/gpu/nvgpu/gk20a/channel_sync_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/channel_sync_gk20a.c
@@ -458,6 +458,9 @@ static int gk20a_channel_semaphore_wait_fd(
                 goto fail;
         }
 
+        /* worker takes one reference */
+        gk20a_semaphore_get(w->sema);
+
         gk20a_channel_alloc_priv_cmdbuf(c, 8, &wait_cmd);
         if (wait_cmd == NULL) {
                 gk20a_err(dev_from_gk20a(c->g),