[Nouveau] [PATCH RFC 01/20] pm: prevent freeing the wrong engine context

[Samuel Pitoiset]

This fixes a crash when multiple PM engine contexts are created.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset at gmail.com>
Reviewed-by: Martin Peres <martin.peres at free.fr>
---
 drm/nouveau/nvkm/engine/pm/base.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drm/nouveau/nvkm/engine/pm/base.c b/drm/nouveau/nvkm/engine/pm/base.c
index 2006c44..274457c 100644
--- a/drm/nouveau/nvkm/engine/pm/base.c
+++ b/drm/nouveau/nvkm/engine/pm/base.c
@@ -332,9 +332,12 @@ static void
 nvkm_perfctx_dtor(struct nvkm_object *object)
 {
 	struct nvkm_pm *ppm = (void *)object->engine;
+	struct nvkm_perfctx *ctx = (void *)object;
+
 	mutex_lock(&nv_subdev(ppm)->mutex);
-	nvkm_engctx_destroy(&ppm->context->base);
-	ppm->context = NULL;
+	nvkm_engctx_destroy(&ctx->base);
+	if (ppm->context == ctx)
+		ppm->context = NULL;
 	mutex_unlock(&nv_subdev(ppm)->mutex);
 }
 
-- 
2.4.2