[PATCH] drm/amdgpu/sriov : Check the memory can be accesssed by ttm_device_clear_dma_mappings.

[Surbhi Kakarya]

On SRIOV environment, if event guard is enabled and VF doesn't
receive an ack from PF for full access, the guest driver load crashes.
This is caused due to the call to ttm_device_clear_dma_mappings with non-initialized
mman during driver tear down.

This patch adds the necessary condition to check if the mman initialization passed or not
and takes the path based on the condition output.

Signed-off-by: skakarya <Surbhi.Kakarya at amd.com>
Change-Id: I1c18c7eb3500687c8b6e7fc414503dcf2a20b94c
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index 598250a380f5..226110be7a2f 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -3984,7 +3984,8 @@ void amdgpu_device_fini_hw(struct amdgpu_device *adev)
 
 	amdgpu_irq_fini_hw(adev);
 
-	ttm_device_clear_dma_mappings(&adev->mman.bdev);
+	if (adev->mman.initialized)
+		ttm_device_clear_dma_mappings(&adev->mman.bdev);
 
 	amdgpu_gart_dummy_page_fini(adev);
 
-- 
2.25.1