[PATCH] media: mediatek: vpu: release reserved memory on remove

[Guangshuo Li]

mtk_vpu_probe() may assign a reserved memory region to the VPU device
with of_reserved_mem_device_init(). The probe failure path releases the
assignment with of_reserved_mem_device_release(), but the normal remove
path does not perform the corresponding cleanup.

As a result, removing the VPU driver after a successful probe can leave
the reserved memory assignment associated with the device after its
lifetime has ended.

Release the reserved memory assignment after freeing the VPU external
firmware memory, matching the cleanup performed by the probe failure
path.

This issue was found by manual code inspection.

Fixes: 3003a180ef6b ("[media] VPU: mediatek: support Mediatek VPU")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Guangshuo Li <lgs201920130244@xxxxxxxxx>
---
 drivers/media/platform/mediatek/vpu/mtk_vpu.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/media/platform/mediatek/vpu/mtk_vpu.c b/drivers/media/platform/mediatek/vpu/mtk_vpu.c
index 8d8319f0cd22..16b5bdc2f2c0 100644
--- a/drivers/media/platform/mediatek/vpu/mtk_vpu.c
+++ b/drivers/media/platform/mediatek/vpu/mtk_vpu.c
@@ -966,6 +966,7 @@ static void mtk_vpu_remove(struct platform_device *pdev)
 		destroy_workqueue(vpu->wdt.wq);
 	vpu_free_ext_mem(vpu, P_FW);
 	vpu_free_ext_mem(vpu, D_FW);
+	of_reserved_mem_device_release(&pdev->dev);
 	mutex_destroy(&vpu->vpu_mutex);
 	clk_unprepare(vpu->clk);
 }
-- 
2.43.0