[PATCH v7 04/17] drm/msm: Synchronize set_sysprof on ctxlock

[Rob Clark <robin.clark@oss.qualcomm.com>]

A user that was perfmon_capable() could try to race setting SYSPROF
param on multiple threads to trigger a reference leak.

Signed-off-by: Rob Clark <robin.clark@oss.qualcomm.com>
---
 drivers/gpu/drm/msm/msm_submitqueue.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/msm/msm_submitqueue.c b/drivers/gpu/drm/msm/msm_submitqueue.c
index 8b5980d5a6a7..233c4f35ab12 100644
--- a/drivers/gpu/drm/msm/msm_submitqueue.c
+++ b/drivers/gpu/drm/msm/msm_submitqueue.c
@@ -9,6 +9,8 @@
 
 int msm_context_set_sysprof(struct msm_context *ctx, struct msm_gpu *gpu, int sysprof)
 {
+	guard(rwsem_write)(&ctx->ctxlock);
+
 	/*
 	 * Since pm_runtime and sysprof_active are both refcounts, we
 	 * call apply the new value first, and then unwind the previous
-- 
2.55.0