From 19965d8259fdabc6806da92adda49684f5bcbec5 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Marek=20Marczykowski-G=C3=B3recki?= Date: Wed, 27 Apr 2022 01:57:15 +0200 Subject: [PATCH] drm/amdgpu: do not use passthrough mode in Xen dom0 MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit While technically Xen dom0 is a virtual machine too, it does have access to most of the hardware so it doesn't need to be considered a "passthrough". Commit b818a5d37454 ("drm/amdgpu/gmc: use PCI BARs for APUs in passthrough") changed how FB is accessed based on passthrough mode. This breaks amdgpu in Xen dom0 with message like this: [drm:dc_dmub_srv_wait_idle [amdgpu]] *ERROR* Error waiting for DMUB idle: status=3 While the reason for this failure is unclear, the passthrough mode is not really necessary in Xen dom0 anyway. So, to unbreak booting affected kernels, disable passthrough mode in this case. Link: https://gitlab.freedesktop.org/drm/amd/-/issues/1985 Fixes: b818a5d37454 ("drm/amdgpu/gmc: use PCI BARs for APUs in passthrough") Signed-off-by: Marek Marczykowski-Górecki Signed-off-by: Alex Deucher Cc: stable@vger.kernel.org --- drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c index a025f080..5e37566 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c @@ -24,6 +24,7 @@ #include #include +#include #include "amdgpu.h" #include "amdgpu_ras.h" @@ -710,7 +711,8 @@ void amdgpu_detect_virtualization(struct amdgpu_device *adev) adev->virt.caps |= AMDGPU_SRIOV_CAPS_ENABLE_IOV; if (!reg) { - if (is_virtual_machine()) /* passthrough mode exclus sriov mod */ + /* passthrough mode exclus sriov mod */ + if (is_virtual_machine() && !xen_initial_domain()) adev->virt.caps |= AMDGPU_PASSTHROUGH_MODE; } -- 2.7.4