1 files changed, 10 insertions, 2 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/channel_gk20a.c b/drivers/gpu/nvgpu/gk20a/channel_gk20a.c
index dae9c8cb..c18a4e5d 100644
--- a/drivers/gpu/nvgpu/gk20a/channel_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/channel_gk20a.c
@@ -719,7 +719,7 @@ static void gk20a_free_channel(struct channel_gk20a *ch)
         struct vm_gk20a *ch_vm = ch->vm;
         unsigned long timeout = gk20a_get_gr_idle_timeout(g);
         struct dbg_session_gk20a *dbg_s;
-
+        bool was_reset;
         gk20a_dbg_fn("");
 
         WARN_ON(ch->g == NULL);
@@ -764,7 +764,15 @@ static void gk20a_free_channel(struct channel_gk20a *ch)
         if (g->fifo.deferred_reset_pending) {
                 gk20a_dbg(gpu_dbg_intr | gpu_dbg_gpu_dbg, "engine reset was"
                            " deferred, running now");
-                gk20a_fifo_reset_engine(g, g->fifo.deferred_fault_engines);
+                was_reset = mutex_is_locked(&g->fifo.gr_reset_mutex);
+                mutex_lock(&g->fifo.gr_reset_mutex);
+                /* if lock is already taken, a reset is taking place
+                so no need to repeat */
+                if (!was_reset) {
+                        gk20a_fifo_reset_engine(g,
+                                g->fifo.deferred_fault_engines);
+                }
+                mutex_unlock(&g->fifo.gr_reset_mutex);
                 g->fifo.deferred_fault_engines = 0;
                 g->fifo.deferred_reset_pending = false;
         }