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From:   Wanpeng Li <kernellwp@gmail.com>
To:     linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc:     Paolo Bonzini <pbonzini@redhat.com>,
        Sean Christopherson <seanjc@google.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        Joerg Roedel <joro@8bytes.org>
Subject: [PATCH] KVM: LAPIC: Disarm LAPIC timer includes pending timer around TSC deadline switch
Date:   Tue, 10 May 2022 02:36:26 -0700
Message-Id: <1652175386-31587-1-git-send-email-wanpengli@tencent.com>
Precedence: bulk

From: Wanpeng Li <wanpengli@tencent.com>

The timer is disarmed when switching between TSC deadline and other modes, 
however, the pending timer is still in-flight, so let's accurately set 
everything to a disarmed state.

Fixes: 4427593258 (KVM: x86: thoroughly disarm LAPIC timer around TSC deadline switch)
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
---
 arch/x86/kvm/lapic.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 66b0eb0bda94..0274d17d91c2 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -1562,6 +1562,7 @@ static void apic_update_lvtt(struct kvm_lapic *apic)
 			kvm_lapic_set_reg(apic, APIC_TMICT, 0);
 			apic->lapic_timer.period = 0;
 			apic->lapic_timer.tscdeadline = 0;
+			atomic_set(&apic->lapic_timer.pending, 0);
 		}
 		apic->lapic_timer.timer_mode = timer_mode;
 		limit_periodic_timer_frequency(apic);
-- 
2.25.1