linux-kernel - [PATCH v3 02/11] KVM: nVMX: Don't set 'dirty

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Message-Id: <20210526132026.270394-3-vkuznets@redhat.com>
Date:   Wed, 26 May 2021 15:20:17 +0200
From:   Vitaly Kuznetsov <vkuznets@...hat.com>
To:     kvm@...r.kernel.org, Paolo Bonzini <pbonzini@...hat.com>
Cc:     Sean Christopherson <seanjc@...gle.com>,
        Wanpeng Li <wanpengli@...cent.com>,
        Jim Mattson <jmattson@...gle.com>,
        Maxim Levitsky <mlevitsk@...hat.com>,
        linux-kernel@...r.kernel.org
Subject: [PATCH v3 02/11] KVM: nVMX: Don't set 'dirty_vmcs12' flag on enlightened VMPTRLD

'dirty_vmcs12' is only checked in prepare_vmcs02_early()/prepare_vmcs02()
and both checks look like:

 'vmx->nested.dirty_vmcs12 || evmptr_is_valid(vmx->nested.hv_evmcs_vmptr)'

so for eVMCS case the flag changes nothing. Drop the assignment to avoid
the confusion.

No functional change intended.

Reported-by: Maxim Levitsky <mlevitsk@...hat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@...hat.com>
---
 arch/x86/kvm/vmx/nested.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index 74ff3fd56ce5..c662278e4793 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -2022,7 +2022,6 @@ static enum nested_evmptrld_status nested_vmx_handle_enlightened_vmptrld(
 			return EVMPTRLD_VMFAIL;
 		}
 
-		vmx->nested.dirty_vmcs12 = true;
 		vmx->nested.hv_evmcs_vmptr = evmcs_gpa;
 
 		evmcs_gpa_changed = true;
-- 
2.31.1