[PATCH 00/18] KVM: x86/mmu: A/D cleanups (on top of kvm_follow_pfn)

From: Sean Christopherson
Date: Thu Oct 10 2024 - 22:11:04 EST


This is effectively an extensive of the kvm_follow_pfn series[*] (and
applies on top of said series), but is x86-specific and is *almost*
entirely related to Accessed and Dirty bits.

There's no central theme beyond cleaning up things that were discovered
when digging deep for the kvm_follow_pfn overhaul, and to a lesser extent
the series to add MGLRU support in KVM x86.

[*] https://lore.kernel.org/all/20241010182427.1434605-1-seanjc@xxxxxxxxxx

Sean Christopherson (18):
KVM: x86/mmu: Flush remote TLBs iff MMU-writable flag is cleared from
RO SPTE
KVM: x86/mmu: Always set SPTE's dirty bit if it's created as writable
KVM: x86/mmu: Fold all of make_spte()'s writable handling into one
if-else
KVM: x86/mmu: Don't force flush if SPTE update clears Accessed bit
KVM: x86/mmu: Don't flush TLBs when clearing Dirty bit in shadow MMU
KVM: x86/mmu: Drop ignored return value from
kvm_tdp_mmu_clear_dirty_slot()
KVM: x86/mmu: Fold mmu_spte_update_no_track() into mmu_spte_update()
KVM: x86/mmu: WARN and flush if resolving a TDP MMU fault clears
MMU-writable
KVM: x86/mmu: Add a dedicated flag to track if A/D bits are globally
enabled
KVM: x86/mmu: Set shadow_accessed_mask for EPT even if A/D bits
disabled
KVM: x86/mmu: Set shadow_dirty_mask for EPT even if A/D bits disabled
KVM: x86/mmu: Use Accessed bit even when _hardware_ A/D bits are
disabled
KVM: x86/mmu: Process only valid TDP MMU roots when aging a gfn range
KVM: x86/mmu: Stop processing TDP MMU roots for test_age if young SPTE
found
KVM: x86/mmu: Dedup logic for detecting TLB flushes on leaf SPTE
changes
KVM: x86/mmu: Set Dirty bit for new SPTEs, even if _hardware_ A/D bits
are disabled
KVM: Allow arch code to elide TLB flushes when aging a young page
KVM: x86: Don't emit TLB flushes when aging SPTEs for mmu_notifiers

arch/x86/kvm/Kconfig | 1 +
arch/x86/kvm/mmu/mmu.c | 72 +++++++-----------------
arch/x86/kvm/mmu/spte.c | 59 ++++++++------------
arch/x86/kvm/mmu/spte.h | 72 ++++++++++++------------
arch/x86/kvm/mmu/tdp_mmu.c | 109 +++++++++++++++++--------------------
arch/x86/kvm/mmu/tdp_mmu.h | 2 +-
virt/kvm/Kconfig | 4 ++
virt/kvm/kvm_main.c | 20 ++-----
8 files changed, 142 insertions(+), 197 deletions(-)


base-commit: 3f9cf3d569fdf7fb451294b636991291965573ce
--
2.47.0.rc1.288.g06298d1525-goog