From 3e8cfbab6c8b4021b6f643922c61e803c8adb1ed Mon Sep 17 00:00:00 2001
From: Lucas Stach <l.stach@pengutronix.de>
Date: Fri, 20 Aug 2021 22:18:28 +0200
Subject: [PATCH] drm/etnaviv: fix MMU context leak on GPU reset
Git-commit: f978a5302f5566480c58ffae64a16d34456801bd
Patch-mainline: v5.15-rc2
References: stable-5.14.7

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@vger.kernel.org # 5.4
Reported-by: Michael Walle <michael@walle.cc>
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Tested-by: Michael Walle <michael@walle.cc>
Tested-by: Marek Vasut <marex@denx.de>
Reviewed-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/gpu/drm/etnaviv/etnaviv_gpu.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
index 9c710924df6b..f420c4f14657 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
@@ -571,6 +571,8 @@ static int etnaviv_hw_reset(struct etnaviv_gpu *gpu)
 
 	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;
-- 
2.26.2