gpu: nvgpu: fix mutex leak on fecs_mutex

In gk20a_gr_reset(), we acquire g->gr.fecs_mutex and call a bunch of APIs
But in case any of these APIs fail, we don't release the mutex and just
return the error leaking the mutex

So the next attempt to acquire g->gr.fecs_mutex results in a deadlock

Fix this by releasing the mutex before returning error

Bug 2015370

Change-Id: I9a0214ff53515f819c6566c7d44d1898027416e1
Signed-off-by: Deepak Nibade <dnibade@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/1589062
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

1 files changed, 9 insertions, 3 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/gr_gk20a.c b/drivers/gpu/nvgpu/gk20a/gr_gk20a.c
index e30c595e..2a20c2d9 100644
--- a/drivers/gpu/nvgpu/gk20a/gr_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/gr_gk20a.c
@@ -5057,16 +5057,22 @@ int gk20a_gr_reset(struct gk20a *g)
         nvgpu_mutex_acquire(&g->gr.fecs_mutex);
 
         err = gk20a_enable_gr_hw(g);
-        if (err)
+        if (err) {
+                nvgpu_mutex_release(&g->gr.fecs_mutex);
                 return err;
+        }
 
         err = gk20a_init_gr_setup_hw(g);
-        if (err)
+        if (err) {
+                nvgpu_mutex_release(&g->gr.fecs_mutex);
                 return err;
+        }
 
         err = gr_gk20a_init_ctxsw(g);
-        if (err)
+        if (err) {
+                nvgpu_mutex_release(&g->gr.fecs_mutex);
                 return err;
+        }
 
         nvgpu_mutex_release(&g->gr.fecs_mutex);