[PATCH 5.10 015/122] drm/etnaviv: fix MMU context leak on GPU reset

[Greg Kroah-Hartman]

From: Lucas Stach <l.stach@xxxxxxxxxxxxxx>

commit f978a5302f5566480c58ffae64a16d34456801bd upstream.

After a reset the GPU is no longer using the MMU context and may be
restarted with a different context. While the mmu_state proeprly was
cleared, the context wasn't unreferenced, leading to a memory leak.

Cc: stable@xxxxxxxxxxxxxxx # 5.4
Reported-by: Michael Walle <michael@xxxxxxxx>
Signed-off-by: Lucas Stach <l.stach@xxxxxxxxxxxxxx>
Tested-by: Michael Walle <michael@xxxxxxxx>
Tested-by: Marek Vasut <marex@xxxxxxx>
Reviewed-by: Christian Gmeiner <christian.gmeiner@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/gpu/drm/etnaviv/etnaviv_gpu.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
@@ -563,6 +563,8 @@ static int etnaviv_hw_reset(struct etnav
 
 	gpu->fe_running = false;
 	gpu->exec_state = -1;
+	if (gpu->mmu_context)
+		etnaviv_iommu_context_put(gpu->mmu_context);
 	gpu->mmu_context = NULL;
 
 	return 0;