drm/amdgpu/virt: skip VM fault handler for VF

VF uses KIQ to access registers. When VM fault occurs, the driver
can't get back the fence of KIQ submission and runs into CPU soft
lockup.

Signed-off-by: Pixel Ding <Pixel.Ding@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Junwei Zhang <Jerry.Zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c

@@ -1237,6 +1237,13 @@ static int gmc_v8_0_process_interrupt(struct amdgpu_device *adev,
 {
 	u32 addr, status, mc_client;
 
+	if (amdgpu_sriov_vf(adev)) {
+		dev_err(adev->dev, "GPU fault detected: %d 0x%08x\n",
+			entry->src_id, entry->src_data);
+		dev_err(adev->dev, " Can't decode VM fault info here on SRIOV VF\n");
+		return 0;
+	}
+
 	addr = RREG32(mmVM_CONTEXT1_PROTECTION_FAULT_ADDR);
 	status = RREG32(mmVM_CONTEXT1_PROTECTION_FAULT_STATUS);
 	mc_client = RREG32(mmVM_CONTEXT1_PROTECTION_FAULT_MCCLIENT);