KVM: x86/mmu: Clear only A-bit (if enabled) when aging TDP MMU SPTEs

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Use tdp_mmu_clear_spte_bits() when clearing the Accessed bit in TDP MMU
SPTEs so as to use an atomic-AND instead of XCHG to clear the A-bit.
Similar to the D-bit story, this will allow KVM to bypass
__handle_changed_spte() by ensuring only the A-bit is modified.

Link: https://lore.kernel.org/all/Y9HcHRBShQgjxsQb@google.com
Signed-off-by: Vipin Sharma <vipinsh@google.com>
Reviewed-by: David Matlack <dmatlack@google.com>
[sean: massage changelog]
Link: https://lore.kernel.org/r/20230321220021.2119033-9-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

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Vipin Sharma 2023-03-21 15:00:16 -07:00 • committed by Sean Christopherson

parent e73008705d

commit 7ee131e3a3

1 changed files with 21 additions and 17 deletions

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arch/x86/kvm/mmu/tdp_mmu.c

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