[RFC PATCH 0/6] KVM: guest memory: Misc enhacnement

From: isaku . yamahata
Date: Thu Jun 15 2023 - 16:12:46 EST


From: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>

Hello. This is an RFC patch series based on KVM gmem [1] and [2]
for the common use of TDX and SEV-SNP. I'd like to discuss three items.

* Flags for kvm_gfn_range:
Roth, By adding flags to kvm_gfn_range, kvm_arch_gmem_invalidate() won't be
needed. Maybe x86 gmem_invalidate callback is still needed, though.

* Page fault error code or how to figure out the private page fault
There is an issue to set kvm_page_fault.is_private. I came up with two new
error codes. Is this a way or any other way?

* VM type: Now we have KVM_X86_PROTECTED_VM. How do we proceed?
- Keep KVM_X86_PROTECTED_VM for its use. Introduce KVM_X86_TDX_VM
- Use KVM_X86_PROTECTED_VM for TDX. (If necessary, introduce another type in
the future)
- any other way?

[1] KVM gmem patches
https://github.com/sean-jc/linux/tree/x86/kvm_gmem_solo

[2] Add AMD Secure Nested Paging (SEV-SNP) Hypervisor Support
https://lore.kernel.org/lkml/20230612042559.375660-1-michael.roth@xxxxxxx/

Isaku Yamahata (6):
KVM: selftests: Fix test_add_overlapping_private_memory_regions()
KVM: selftests: Fix guest_memfd()
KVM: x86/mmu: Pass round full 64-bit error code for the KVM page fault
KVM: x86: Introduce PFERR_GUEST_ENC_MASK to indicate fault is private
KVM: Add flags to struct kvm_gfn_range
KVM: x86: Add is_vm_type_supported callback

arch/x86/include/asm/kvm-x86-ops.h | 1 +
arch/x86/include/asm/kvm_host.h | 5 +++++
arch/x86/include/uapi/asm/kvm.h | 1 +
arch/x86/kvm/mmu/mmu.c | 14 +++++++++-----
arch/x86/kvm/mmu/mmu_internal.h | 8 ++++----
arch/x86/kvm/mmu/mmutrace.h | 2 +-
arch/x86/kvm/mmu/paging_tmpl.h | 4 ++--
arch/x86/kvm/svm/svm.c | 7 +++++++
arch/x86/kvm/vmx/vmx.c | 6 ++++++
arch/x86/kvm/x86.c | 10 +++++++++-
arch/x86/kvm/x86.h | 2 ++
include/linux/kvm_host.h | 11 ++++++++++-
tools/testing/selftests/kvm/guest_memfd_test.c | 4 ++--
.../selftests/kvm/set_memory_region_test.c | 16 ++++++++++++++--
virt/kvm/guest_mem.c | 10 +++++++---
virt/kvm/kvm_main.c | 4 +++-
16 files changed, 83 insertions(+), 22 deletions(-)


base-commit: be8abcec83c87d4e15ae04816b685fe260c4bcfd
--
2.25.1