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Message-ID: <73a4655a-2c63-3209-1153-2fc816e8990e@redhat.com>
Date:   Wed, 5 Jul 2023 10:35:28 +1000
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Subject: Re: [RESEND PATCH v5 09/11] KVM: arm64: Flush only the memslot after
 write-protect
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To:     Raghavendra Rao Ananta <rananta@google.com>,
        Oliver Upton <oliver.upton@linux.dev>,
        Marc Zyngier <maz@kernel.org>,
        James Morse <james.morse@arm.com>,
        Suzuki K Poulose <suzuki.poulose@arm.com>
Cc:     Paolo Bonzini <pbonzini@redhat.com>,
        Sean Christopherson <seanjc@google.com>,
        Huacai Chen <chenhuacai@kernel.org>,
        Zenghui Yu <yuzenghui@huawei.com>,
        Anup Patel <anup@brainfault.org>,
        Atish Patra <atishp@atishpatra.org>,
        Jing Zhang <jingzhangos@google.com>,
        Colton Lewis <coltonlewis@google.com>,
        David Matlack <dmatlack@google.com>,
        linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev,
        linux-mips@vger.kernel.org, kvm-riscv@lists.infradead.org,
        linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org,
        kvm@vger.kernel.org
References: <20230621175002.2832640-1-rananta@google.com>
 <20230621175002.2832640-10-rananta@google.com>
From:   Gavin Shan <gshan@redhat.com>
In-Reply-To: <20230621175002.2832640-10-rananta@google.com>
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Precedence: bulk

On 6/22/23 03:50, Raghavendra Rao Ananta wrote:
> After write-protecting the region, currently KVM invalidates
> the entire TLB entries using kvm_flush_remote_tlbs(). Instead,
> scope the invalidation only to the targeted memslot. If
> supported, the architecture would use the range-based TLBI
> instructions to flush the memslot or else fallback to flushing
> all of the TLBs.
> 
> Signed-off-by: Raghavendra Rao Ananta <rananta@google.com>
> ---
>   arch/arm64/kvm/mmu.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 

Reviewed-by: Gavin Shan <gshan@redhat.com>

> diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
> index c3ec2141c3284..94f10e670c100 100644
> --- a/arch/arm64/kvm/mmu.c
> +++ b/arch/arm64/kvm/mmu.c
> @@ -992,7 +992,7 @@ static void kvm_mmu_wp_memory_region(struct kvm *kvm, int slot)
>   	write_lock(&kvm->mmu_lock);
>   	stage2_wp_range(&kvm->arch.mmu, start, end);
>   	write_unlock(&kvm->mmu_lock);
> -	kvm_flush_remote_tlbs(kvm);
> +	kvm_flush_remote_tlbs_memslot(kvm, memslot);
>   }
>   
>   /**