Re: [PATCH] drm/amd/amdgpu: Not request init data for MS_HYPERV with vega10

[Paul Menzel]

[Cc: +x86 folks]

Dear Alex, dear x86 folks,


x86 folks, can you think of alternatives to access `X86_HYPER_MS_HYPERV` 
from `arch/x86/include/asm/hypervisor.h` without any preprocessor ifdef-ery?


Am 11.04.22 um 18:28 schrieb Alex Deucher:
> On Mon, Apr 11, 2022 at 11:28 AM Paul Menzel wrote:

[…]

> > Am 11.04.22 um 15:59 schrieb Yongqiang Sun:
> > > MS_HYPERV with vega10 doesn't have the interface to process
> > > request init data msg.
> >
> > Should some Hyper-V folks be added to the reviewers list too?
> >
> > > Check hypervisor type to not send the request for MS_HYPERV.
> >
> > Please add a blank line between paragraphs.
> >
> > > Signed-off-by: Yongqiang Sun <yongqiang.sun@xxxxxxx>
> > > ---
> > >    drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c | 12 ++++++++++--
> > >    1 file changed, 10 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
> > > index 933c41f77c92..56b130ec44a9 100644
> > > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
> > > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
> > > @@ -23,6 +23,10 @@
> > >
> > >    #include <linux/module.h>
> > >
> > > +#ifdef CONFIG_X86
> > > +#include <asm/hypervisor.h>
> > > +#endif
> > > +
> > >    #include <drm/drm_drv.h>
> > >
> > >    #include "amdgpu.h"
> > > @@ -721,8 +725,12 @@ void amdgpu_detect_virtualization(struct amdgpu_device *adev)
> > >                        break;
> > >                case CHIP_VEGA10:
> > >                        soc15_set_virt_ops(adev);
> > > -                     /* send a dummy GPU_INIT_DATA request to host on vega10 */
> > > -                     amdgpu_virt_request_init_data(adev);
> > > +#ifdef CONFIG_X86
> > > +                     /* not send GPU_INIT_DATA with MS_HYPERV*/
> > > +                     if (hypervisor_is_type(X86_HYPER_MS_HYPERV) == false)
> > > +#endif
> >
> > Why guard everything with CONFIG_X86? (If it’s needed, it should be done
> > in C code.)
>
> X86_HYPER_MS_HYPERV only available on x86.

Sorry, I missed the X86 dependency when quickly looking at the Hyper-V 
stub IOMMU driver `drivers/iommu/hyperv-iommu.c`, but missed that 
`HYPERV_IOMMU` has `depends on HYPERV && X86`.


Kind regards,

Paul


> > > +                             /* send a dummy GPU_INIT_DATA request to host on vega10 */
> > > +                             amdgpu_virt_request_init_data(adev);
> > >                        break;
> > >                case CHIP_VEGA20:
> > >                case CHIP_ARCTURUS:
> >
> >
> > Kind regards,
> >
> > Paul