gpu: nvgpu: Fix race condition during poweron

When two or more apps ran simultaneously
First app context sets power_on flag & starts init
Other app context check the power_on flag
and try to use GPU without init completed
Which makes aother apps to assert

Added mutex to synchronize poweron access

Bug 200297265

Change-Id: Ie138f7f43bb0dd3304ed91ae3649a6a4947bee91
Signed-off-by: skadamati <skadamati@nvidia.com>
Reviewed-on: https://git-master/r/1511436
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/gk20a.h b/drivers/gpu/nvgpu/gk20a/gk20a.h
index 9203882c..d45477fc 100644
--- a/drivers/gpu/nvgpu/gk20a/gk20a.h
+++ b/drivers/gpu/nvgpu/gk20a/gk20a.h
@@ -1075,6 +1075,7 @@ struct gk20a {
 #endif
         unsigned int ch_wdt_timeout_ms;
 
+        struct nvgpu_mutex poweron_lock;
         struct nvgpu_mutex poweroff_lock;
 
         /* Channel priorities */