2 files changed, 13 insertions, 2 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/channel_gk20a.c b/drivers/gpu/nvgpu/gk20a/channel_gk20a.c
index 34b62ac4..c09586c5 100644
--- a/drivers/gpu/nvgpu/gk20a/channel_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/channel_gk20a.c
@@ -312,10 +312,13 @@ void channel_gk20a_unbind(struct channel_gk20a *ch_gk20a)
          * resource at this point
          * if not, then it will be destroyed at channel_free()
          */
+        mutex_lock(&ch_gk20a->sync_lock);
         if (ch_gk20a->sync && ch_gk20a->sync->aggressive_destroy) {
+
                 ch_gk20a->sync->destroy(ch_gk20a->sync);
                 ch_gk20a->sync = NULL;
         }
+        mutex_unlock(&ch_gk20a->sync_lock);
 }
 
 int channel_gk20a_alloc_inst(struct gk20a *g, struct channel_gk20a *ch)
@@ -375,10 +378,10 @@ void gk20a_channel_abort(struct channel_gk20a *ch)
         ch->g->ops.fifo.disable_channel(ch);
 
         /* ensure no fences are pending */
-        mutex_lock(&ch->submit_lock);
+        mutex_lock(&ch->sync_lock);
         if (ch->sync)
                 ch->sync->set_min_eq_max(ch->sync);
-        mutex_unlock(&ch->submit_lock);
+        mutex_unlock(&ch->sync_lock);
 
         /* release all job semaphores (applies only to jobs that use
            semaphore synchronization) */
@@ -812,10 +815,12 @@ static void gk20a_free_channel(struct channel_gk20a *ch)
         channel_gk20a_free_priv_cmdbuf(ch);
 
         /* sync must be destroyed before releasing channel vm */
+        mutex_lock(&ch->sync_lock);
         if (ch->sync) {
                 ch->sync->destroy(ch->sync);
                 ch->sync = NULL;
         }
+        mutex_unlock(&ch->sync_lock);
 
         /* release channel binding to the as_share */
         if (ch_vm->as_share)
@@ -1772,11 +1777,13 @@ void gk20a_channel_update(struct channel_gk20a *c, int nr_completed)
          * the sync resource
          */
         if (list_empty(&c->jobs)) {
+                mutex_lock(&c->sync_lock);
                 if (c->sync && c->sync->aggressive_destroy &&
                           gk20a_fence_is_expired(c->last_submit.post_fence)) {
                         c->sync->destroy(c->sync);
                         c->sync = NULL;
                 }
+                mutex_unlock(&c->sync_lock);
         }
         mutex_unlock(&c->jobs_lock);
         mutex_unlock(&c->submit_lock);
@@ -1889,6 +1896,7 @@ int gk20a_submit_channel_gpfifo(struct channel_gk20a *c,
 
         mutex_lock(&c->submit_lock);
 
+        mutex_lock(&c->sync_lock);
         if (!c->sync) {
                 c->sync = gk20a_channel_sync_create(c);
                 if (!c->sync) {
@@ -1901,6 +1909,7 @@ int gk20a_submit_channel_gpfifo(struct channel_gk20a *c,
                 if (err)
                         return err;
         }
+        mutex_unlock(&c->sync_lock);
 
         /*
          * optionally insert syncpt wait in the beginning of gpfifo submission
@@ -2053,6 +2062,7 @@ int gk20a_init_channel_support(struct gk20a *g, u32 chid)
         mutex_init(&c->jobs_lock);
         mutex_init(&c->submit_lock);
         mutex_init(&c->timeout.lock);
+        mutex_init(&c->sync_lock);
         INIT_DELAYED_WORK(&c->timeout.wq, gk20a_channel_timeout_handler);
         INIT_LIST_HEAD(&c->jobs);
 #if defined(CONFIG_GK20A_CYCLE_STATS)
diff --git a/drivers/gpu/nvgpu/gk20a/channel_gk20a.h b/drivers/gpu/nvgpu/gk20a/channel_gk20a.h
index 3e18e053..794d8228 100644
--- a/drivers/gpu/nvgpu/gk20a/channel_gk20a.h
+++ b/drivers/gpu/nvgpu/gk20a/channel_gk20a.h
@@ -166,6 +166,7 @@ struct channel_gk20a {
         struct nvgpu_notification *error_notifier;
         void *error_notifier_va;
 
+        struct mutex sync_lock;
         struct gk20a_channel_sync *sync;
 
 #ifdef CONFIG_TEGRA_GR_VIRTUALIZATION