Hello Yuan,
On Thu, Sep 02, 2021 at 11:23:50PM +0000, Yao, Yuan wrote:
> >-----Original Message-----
> >From: Ashish Kalra <Ashish.Kalra@xxxxxxx>
> >Sent: Thursday, September 02, 2021 22:05
> >To: yuan.yao@xxxxxxxxxxxxxxx
> >Cc: Thomas.Lendacky@xxxxxxx; armbru@xxxxxxxxxx; ashish.kalra@xxxxxxx; brijesh.singh@xxxxxxx;
> >dgilbert@xxxxxxxxxx; ehabkost@xxxxxxxxxx; Yamahata, Isaku <isaku.yamahata@xxxxxxxxx>; kvm@xxxxxxxxxxxxxxx;
> >mst@xxxxxxxxxx; mtosatti@xxxxxxxxxx; pbonzini@xxxxxxxxxx; qemu-devel@xxxxxxxxxx; Yao, Yuan
> ><yuan.yao@xxxxxxxxx>
> >Subject: [RFC][PATCH v1 00/10] Enable encrypted guest memory access in QEMU
> >
> >> - We introduce another new vm level ioctl focus on the encrypted
> >> guest memory accessing:
> >>
> >> KVM_MEMORY_ENCRYPT_{READ,WRITE}_MEMORY
> >>
> >> struct kvm_rw_memory rw;
> >> rw.addr = gpa_OR_hva;
> >> rw.buf = (__u64)src;
> >> rw.len = len;
> >> kvm_vm_ioctl(kvm_state,
> >> KVM_MEMORY_ENCRYPT_{READ,WRITE}_MEMORY,
> >> &rw);
> >>
> >> This new ioctl has more neutral and general name for its
> >> purpose, the debugging support of AMD SEV and INTEL TDX
> >> can be covered by a unify QEMU implementation on x86 with this
> >> ioctl. Although only INTEL TD guest is supported in this series,
> >> AMD SEV could be also supported with implementation of this
> >> ioctl in KVM, plus small modifications in QEMU to enable the
> >> unify part.
> >
> >A general comment, we have sev_ioctl() interface for SEV guests and
> >probably this new vm level ioctl will not work for us.
> >
> >It probably makes more sense to do this TDX/SEV level abstraction
> >using the Memory Region's ram_debug_ops, which can point these to
> >TDX specific vm level ioctl and SEV specific ioctl at the lowest
> >level of this interface.
> >
> Hi Ashish,
>
> Yes, this new ioctl is now working as the low-level interface for
> Memory Region's ram_debug_ops. SEV can use
> kvm_setup_set_memory_region_debug_ops() to install a new
> callback to KVM for installing SEV only low-level implementation,
> then call kvm_set_memory_region_debug_ops() to do Memory
> Region's ram_debug_ops installation later.
>
>
Ok. Yes i think that should work.
Thanks,
Ashish
