linux-kernel - [PATCH v2 16/17] KVM: x86/mmu: Sync roots after MMU load iff load as successful

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20210305011101.3597423-17-seanjc@google.com>
Date:   Thu,  4 Mar 2021 17:11:00 -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 v2 16/17] 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 4f66ca0f5f68..bceff7d815c3 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -4850,10 +4850,11 @@ 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