Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Sat, 22 Jul 2023 02:22:49 +0000
In-Reply-To: <20230722022251.3446223-1-rananta@google.com>
Mime-Version: 1.0
References: <20230722022251.3446223-1-rananta@google.com>
Message-ID: <20230722022251.3446223-11-rananta@google.com>
Subject: [PATCH v7 10/12] KVM: arm64: Flush only the memslot after write-protect
From:   Raghavendra Rao Ananta <rananta@google.com>
To:     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>,
        Reiji Watanabe <reijiw@google.com>,
        Colton Lewis <coltonlewis@google.com>,
        Raghavendra Rao Anata <rananta@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, Gavin Shan <gshan@redhat.com>,
        Shaoqin Huang <shahuang@redhat.com>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

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>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Shaoqin Huang <shahuang@redhat.com>
---
 arch/arm64/kvm/mmu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index 387f2215fde7..985f605e2abc 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -1082,7 +1082,7 @@ 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);
 }
 
 /**
-- 
2.41.0.487.g6d72f3e995-goog