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charset="UTF-8" X-Rspam-User: X-Rspamd-Server: rspam03 X-Stat-Signature: johaetkowrnbqk67pmouhmy6yyxoawnz X-Rspamd-Queue-Id: E86611C0009 X-HE-Tag: 1676607886-770411 X-HE-Meta: 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 8xadauQe DcyJrhhIzDjYdGyC6mRXT2k1DQJX02sTa/IsTjur4f3qmRJxm2qdyeYU5KY7hCh5RWIUxrD2/fFRb8cywG9lItTG65StIzy/IcnHYmhAEMrjLGPaVxkdT/wIn4Ceu14ONizTonk/CRSomlpsbhHUJjAl4Y/l6SGGldG3jgTDspSXHcE/XgtGv0XFqNN0Z5d/Sq8aWWBNxuHaVFTxKi2+7a29Z7mgZvpfUfRRqF+Ajj7zAwevAJ28FYKxOy75v495j+jzcoao8wt/dsXiFo/lVl0XZ9ju70a/2XvT6DpSplqU/yHsRXYeWcBycxA== 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 with Radix MMU enabled. > > 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/powerpc/include/asm/kvm_host.h | 18 ++++++ > arch/powerpc/include/asm/kvm_ppc.h | 14 +---- > arch/powerpc/kvm/book3s.c | 7 +++ > arch/powerpc/kvm/book3s.h | 2 + > arch/powerpc/kvm/book3s_64_mmu_radix.c | 78 +++++++++++++++++++++++++- > arch/powerpc/kvm/book3s_hv.c | 10 ++-- > 6 files changed, 110 insertions(+), 19 deletions(-) Adding Michael, Nicholas and Christophe. I'm not sure who I should add for this patch. Can you please add any interested parties that I've missed? Thank you.