[PATCH AUTOSEL 5.4 06/45] drm/amdgpu: avoid dereferencing a NULL pointer

From: Sasha Levin
Date: Mon Aug 10 2020 - 15:25:44 EST


From: Jack Xiao <Jack.Xiao@xxxxxxx>

[ Upstream commit 55611b507fd6453d26030c0c0619fdf0c262766d ]

Check if irq_src is NULL to avoid dereferencing a NULL pointer,
for MES ring is uneccessary to recieve an interrupt notification.

Signed-off-by: Jack Xiao <Jack.Xiao@xxxxxxx>
Acked-by: Alex Deucher <alexander.deucher@xxxxxxx>
Reviewed-by: Hawking Zhang <Hawking.Zhang@xxxxxxx>
Reviewed-by: Christian König <christian.koenig@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c | 19 ++++++++++++-------
1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c
index 23085b352cf2d..c212d5fc665c6 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c
@@ -404,7 +404,9 @@ int amdgpu_fence_driver_start_ring(struct amdgpu_ring *ring,
ring->fence_drv.gpu_addr = adev->uvd.inst[ring->me].gpu_addr + index;
}
amdgpu_fence_write(ring, atomic_read(&ring->fence_drv.last_seq));
- amdgpu_irq_get(adev, irq_src, irq_type);
+
+ if (irq_src)
+ amdgpu_irq_get(adev, irq_src, irq_type);

ring->fence_drv.irq_src = irq_src;
ring->fence_drv.irq_type = irq_type;
@@ -539,8 +541,9 @@ void amdgpu_fence_driver_fini(struct amdgpu_device *adev)
/* no need to trigger GPU reset as we are unloading */
amdgpu_fence_driver_force_completion(ring);
}
- amdgpu_irq_put(adev, ring->fence_drv.irq_src,
- ring->fence_drv.irq_type);
+ if (ring->fence_drv.irq_src)
+ amdgpu_irq_put(adev, ring->fence_drv.irq_src,
+ ring->fence_drv.irq_type);
drm_sched_fini(&ring->sched);
del_timer_sync(&ring->fence_drv.fallback_timer);
for (j = 0; j <= ring->fence_drv.num_fences_mask; ++j)
@@ -576,8 +579,9 @@ void amdgpu_fence_driver_suspend(struct amdgpu_device *adev)
}

/* disable the interrupt */
- amdgpu_irq_put(adev, ring->fence_drv.irq_src,
- ring->fence_drv.irq_type);
+ if (ring->fence_drv.irq_src)
+ amdgpu_irq_put(adev, ring->fence_drv.irq_src,
+ ring->fence_drv.irq_type);
}
}

@@ -603,8 +607,9 @@ void amdgpu_fence_driver_resume(struct amdgpu_device *adev)
continue;

/* enable the interrupt */
- amdgpu_irq_get(adev, ring->fence_drv.irq_src,
- ring->fence_drv.irq_type);
+ if (ring->fence_drv.irq_src)
+ amdgpu_irq_get(adev, ring->fence_drv.irq_src,
+ ring->fence_drv.irq_type);
}
}

--
2.25.1