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charset="UTF-8" X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 1E6AC80011 X-Rspam-User: X-Stat-Signature: nh9jpq6machhghzkyeckbgg81esywyzz X-HE-Tag: 1676607632-493341 X-HE-Meta: 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 oLBenV4V JfdijsrdNyAF/8YVnRNpjCAOCnbfUXxUfjX769Bb6umcL6pdTtltLtkvsd2fpe9Z3v91QtnxYt3L8T/hSJGH0eu0uOq8BUSRger+Jl7SrkNKdE5hn9qQI724CEgNbGhBWYrYFBEcAbv9wdZDmToCKF0xUapxErXiTe0Qiw/7LRIbhrgDDx7elt7DnP2GyHAlGaO6GH7Wr8Lsvq7VrFcqtPvHuMXH1MEkz9fTX2LsGQ3c2Z+Y1i0RqB8PO7YEh7wRXabtF4VG3DMIPNtBw/1EXV3NRBZfZHTTU0xLv4t13UpgpT70uDlVltj2pPA== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, Feb 16, 2023 at 9:12 PM Yu Zhao wrote: > > This patch adds kvm_arch_test_clear_young() for the vast majority of > VMs that are not nested and run on hardware that sets the accessed bit > in TDP MMU page tables. > > It relies on two techniques, RCU and cmpxchg, to safely test and clear > the accessed bit without taking the MMU lock. The former protects KVM > page tables from being freed while the latter clears the accessed bit > atomically against both the hardware and other software page table > walkers. > > Signed-off-by: Yu Zhao > --- > arch/x86/include/asm/kvm_host.h | 27 ++++++++++++++++++++++ > arch/x86/kvm/mmu/spte.h | 12 ---------- > arch/x86/kvm/mmu/tdp_mmu.c | 41 +++++++++++++++++++++++++++++++++ > 3 files changed, 68 insertions(+), 12 deletions(-) Adding Sean and David. Can you please add other interested parties that I've missed? Thanks.