1 files changed, 9 insertions, 3 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/gk20a_sysfs.c b/drivers/gpu/nvgpu/gk20a/gk20a_sysfs.c
index 9bf6acec..6611b120 100644
--- a/drivers/gpu/nvgpu/gk20a/gk20a_sysfs.c
+++ b/drivers/gpu/nvgpu/gk20a/gk20a_sysfs.c
@@ -511,15 +511,21 @@ static ssize_t mscg_enable_store(struct device *dev,
                         g->mscg_enabled = true;
                         if (g->ops.pmu.pmu_is_lpwr_feature_supported(g,
                                         PMU_PG_LPWR_FEATURE_MSCG)) {
-                                if (!pmu->mscg_stat)
-                                        pmu->mscg_stat = PMU_MSCG_ENABLED;
+                                if (!ACCESS_ONCE(pmu->mscg_stat)) {
+                                        WRITE_ONCE(pmu->mscg_stat,
+                                                PMU_MSCG_ENABLED);
+                                        /* make status visible */
+                                        smp_mb();
+                                }
                         }
 
                 } else if (!val && g->mscg_enabled) {
                         if (g->ops.pmu.pmu_is_lpwr_feature_supported(g,
                                         PMU_PG_LPWR_FEATURE_MSCG)) {
                                 gk20a_pmu_pg_global_enable(g, false);
-                                pmu->mscg_stat = PMU_MSCG_DISABLED;
+                                WRITE_ONCE(pmu->mscg_stat, PMU_MSCG_DISABLED);
+                                /* make status visible */
+                                smp_mb();
                                 g->mscg_enabled = false;
                                 if (g->elpg_enabled)
                                         gk20a_pmu_pg_global_enable(g, true);