Re: [PATCH v3 00/22] https://www.spinics.net/lists/kvm/msg267878.html

[Paolo Bonzini]

Uh-oh, wrong subject.  Should be "KVM MMU refactoring part 2: role changes".

Supersedes: <20220221162243.683208-1-pbonzini@xxxxxxxxxx>

Paolo

On 4/14/22 09:39, Paolo Bonzini wrote:
> Right now the "MMU role" is a messy mix of the shadow page table format
> and the CPU paging mode (CR0/CR4/EFER, SMM, guest mode, etc).  Whenever
> something is different between the MMU and the CPU, it is stored as an
> extra field in struct kvm_mmu; for extra bonus complication, sometimes
> the same thing is stored in both the role and an extra field.
>
> This series cleans up things by putting the two in separate fields,
> so that the "MMU role" represents exactly the role of the root page.
> This in turn makes it possible to eliminate various fields that are
> now redundant with either the CPU or te MMU role.
>
> These patches have mostly been posted and reviewed already[1], and I
> have now retested them on top of kvm/next.
>
> Paolo
>
> [1] https://patchew.org/linux/20220221162243.683208-1-pbonzini@xxxxxxxxxx/
>
> Paolo Bonzini (21):
>    KVM: x86/mmu: nested EPT cannot be used in SMM
>    KVM: x86/mmu: constify uses of struct kvm_mmu_role_regs
>    KVM: x86/mmu: pull computation of kvm_mmu_role_regs to kvm_init_mmu
>    KVM: x86/mmu: rephrase unclear comment
>    KVM: x86/mmu: remove "bool base_only" arguments
>    KVM: x86/mmu: split cpu_role from mmu_role
>    KVM: x86/mmu: do not recompute root level from kvm_mmu_role_regs
>    KVM: x86/mmu: remove ept_ad field
>    KVM: x86/mmu: remove kvm_calc_shadow_root_page_role_common
>    KVM: x86/mmu: cleanup computation of MMU roles for two-dimensional
>      paging
>    KVM: x86/mmu: cleanup computation of MMU roles for shadow paging
>    KVM: x86/mmu: store shadow EFER.NX in the MMU role
>    KVM: x86/mmu: remove extended bits from mmu_role, rename field
>    KVM: x86/mmu: rename kvm_mmu_role union
>    KVM: x86/mmu: remove redundant bits from extended role
>    KVM: x86/mmu: remove valid from extended role
>    KVM: x86/mmu: simplify and/or inline computation of shadow MMU roles
>    KVM: x86/mmu: pull CPU mode computation to kvm_init_mmu
>    KVM: x86/mmu: replace shadow_root_level with root_role.level
>    KVM: x86/mmu: replace root_level with cpu_role.base.level
>    KVM: x86/mmu: replace direct_map with root_role.direct
>
> Sean Christopherson (1):
>    KVM: x86: Clean up and document nested #PF workaround
>
>   arch/x86/include/asm/kvm_host.h |  19 +-
>   arch/x86/kvm/mmu.h              |   2 +-
>   arch/x86/kvm/mmu/mmu.c          | 376 ++++++++++++++------------------
>   arch/x86/kvm/mmu/paging_tmpl.h  |  14 +-
>   arch/x86/kvm/mmu/tdp_mmu.c      |   4 +-
>   arch/x86/kvm/svm/nested.c       |  18 +-
>   arch/x86/kvm/svm/svm.c          |   2 +-
>   arch/x86/kvm/vmx/nested.c       |  15 +-
>   arch/x86/kvm/vmx/vmx.c          |   2 +-
>   arch/x86/kvm/x86.c              |  33 ++-
>   10 files changed, 219 insertions(+), 266 deletions(-)