[PATCH v2 1/2] KVM: nSVM: always restore the L1's GIF on migration

From: Maxim Levitsky <mlevitsk@redhat.com>
To: kvm@vger.kernel.org
Cc: Borislav Petkov <bp@alien8.de>,
	Paolo Bonzini <pbonzini@redhat.com>,
	x86@kernel.org (maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)),
	Wanpeng Li <wanpengli@tencent.com>,
	Jim Mattson <jmattson@google.com>,
	"H. Peter Anvin" <hpa@zytor.com>, Ingo Molnar <mingo@redhat.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	linux-kernel@vger.kernel.org, Cathy Avery <cavery@redhat.com>,
	Sean Christopherson <seanjc@google.com>,
	Vitaly Kuznetsov <vkuznets@redhat.com>,
	Joerg Roedel <joro@8bytes.org>,
	Maxim Levitsky <mlevitsk@redhat.com>
Subject: [PATCH v2 1/2] KVM: nSVM: always restore the L1's GIF on migration
Date: Tue,  4 May 2021 17:39:35 +0300	[thread overview]
Message-ID: <20210504143936.1644378-2-mlevitsk@redhat.com> (raw)
In-Reply-To: <20210504143936.1644378-1-mlevitsk@redhat.com>

While usually the L1's GIF is set while L2 runs, and usually
migration nested state is loaded after a vCPU reset which
also sets L1's GIF to true, this is not guaranteed.

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
---
 arch/x86/kvm/svm/nested.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index 32400cba608d..b331446f67f3 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -1314,6 +1314,8 @@ static int svm_set_nested_state(struct kvm_vcpu *vcpu,
 	else
 		svm->nested.vmcb02.ptr->save = svm->vmcb01.ptr->save;
 
+	svm_set_gif(svm, !!(kvm_state->flags & KVM_STATE_NESTED_GIF_SET));
+
 	svm->nested.nested_run_pending =
 		!!(kvm_state->flags & KVM_STATE_NESTED_RUN_PENDING);
 
-- 
2.26.2

