linux-kernel - [PATCH 14/15] KVM: x86/mmu: Sync roots after MMU load iff load as successful

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Message-Id: <20210302184540.2829328-15-seanjc@google.com>
Date:   Tue,  2 Mar 2021 10:45:39 -0800
From:   Sean Christopherson <seanjc@...gle.com>
To:     Paolo Bonzini <pbonzini@...hat.com>
Cc:     Sean Christopherson <seanjc@...gle.com>,
        Vitaly Kuznetsov <vkuznets@...hat.com>,
        Wanpeng Li <wanpengli@...cent.com>,
        Jim Mattson <jmattson@...gle.com>,
        Joerg Roedel <joro@...tes.org>, kvm@...r.kernel.org,
        linux-kernel@...r.kernel.org, Ben Gardon <bgardon@...gle.com>,
        Brijesh Singh <brijesh.singh@....com>,
        Tom Lendacky <thomas.lendacky@....com>
Subject: [PATCH 14/15] KVM: x86/mmu: Sync roots after MMU load iff load as successful

For clarity, explicitly skip syncing roots if the MMU load failed
instead of relying on the !VALID_PAGE check in kvm_mmu_sync_roots().

Signed-off-by: Sean Christopherson <seanjc@...gle.com>
---
 arch/x86/kvm/mmu/mmu.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 86432d6a4092..34eeb39ee0f9 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -4818,10 +4818,11 @@ int kvm_mmu_load(struct kvm_vcpu *vcpu)
 	else
 		r = mmu_alloc_shadow_roots(vcpu);
 	write_unlock(&vcpu->kvm->mmu_lock);
+	if (r)
+		goto out;
 
 	kvm_mmu_sync_roots(vcpu);
-	if (r)
-		goto out;
+
 	kvm_mmu_load_pgd(vcpu);
 	static_call(kvm_x86_tlb_flush_current)(vcpu);
 out:
-- 
2.30.1.766.gb4fecdf3b7-goog