[RFC PATCH 3/5] drm/amdgpu: set passthrough mode for xen pvh/hvm

From: Huang Rui
Date: Sun Mar 12 2023 - 08:02:50 EST


There is an second stage translation between the guest machine address
and host machine address in Xen PVH/HVM. The PCI bar address in the xen
guest kernel are not translated at the second stage on Xen PVH/HVM, so
it's not the real physical address that hardware would like to know, so
we need to set passthrough mode for Xen PVH/HVM as well.

Signed-off-by: Huang Rui <ray.huang@xxxxxxx>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
index f2e2cbaa7fde..7b4369eba19d 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
@@ -743,7 +743,8 @@ void amdgpu_detect_virtualization(struct amdgpu_device *adev)

if (!reg) {
/* passthrough mode exclus sriov mod */
- if (is_virtual_machine() && !xen_initial_domain())
+ if (is_virtual_machine() &&
+ !(xen_initial_domain() && xen_pv_domain()))
adev->virt.caps |= AMDGPU_PASSTHROUGH_MODE;
}

--
2.25.1