[PATCH] drm/amdgpu: validate process_context_addr for the MES shader debugger

[Prike Liang]

The following page fault was observed during the exit moment of the
HIP test process. In this particular error case, the HIP test
(./MemcpyPerformance -h) does not require the AQL queue. As a result,
the process_context_addr was not assigned when the KFD process was
released, ultimately leading to this page fault during the execution of
kfd_process_dequeue_from_all_devices().

[345962.294891] amdgpu 0000:03:00.0: amdgpu: [gfxhub] page fault (src_id:0 ring:153 vmid:0 pasid:0)
[345962.295333] amdgpu 0000:03:00.0: amdgpu:   in page starting at address 0x0000000000000000 from client 10
[345962.295775] amdgpu 0000:03:00.0: amdgpu: GCVM_L2_PROTECTION_FAULT_STATUS:0x00000B33
[345962.296097] amdgpu 0000:03:00.0: amdgpu:     Faulty UTCL2 client ID: CPC (0x5)
[345962.296394] amdgpu 0000:03:00.0: amdgpu:     MORE_FAULTS: 0x1
[345962.296633] amdgpu 0000:03:00.0: amdgpu:     WALKER_ERROR: 0x1
[345962.296876] amdgpu 0000:03:00.0: amdgpu:     PERMISSION_FAULTS: 0x3
[345962.297135] amdgpu 0000:03:00.0: amdgpu:     MAPPING_ERROR: 0x1
[345962.297377] amdgpu 0000:03:00.0: amdgpu:     RW: 0x0
[345962.297682] amdgpu 0000:03:00.0: amdgpu: [gfxhub] page fault (src_id:0 ring:169 vmid:0 pasid:0)

Signed-off-by: Prike Liang <Prike.Liang at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_mes.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_mes.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_mes.c
index cee38bb6cfaf..4d313144cc4b 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_mes.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_mes.c
@@ -1062,6 +1062,11 @@ int amdgpu_mes_flush_shader_debugger(struct amdgpu_device *adev,
 		return -EINVAL;
 	}
 
+	if (!process_context_addr) {
+		dev_warn(adev->dev, "invalidated process context addr\n");
+		return -EINVAL;
+	}
+
 	op_input.op = MES_MISC_OP_SET_SHADER_DEBUGGER;
 	op_input.set_shader_debugger.process_context_addr = process_context_addr;
 	op_input.set_shader_debugger.flags.process_ctx_flush = true;
-- 
2.34.1