linux-kernel - [PATCH 2/3] KVM: x86: really disarm lapic timer when clearing TMICT

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Date:   Fri,  6 Oct 2017 19:25:54 +0200
From:   Radim Krčmář <rkrcmar@...hat.com>
To:     linux-kernel@...r.kernel.org, kvm@...r.kernel.org
Cc:     Paolo Bonzini <pbonzini@...hat.com>,
        Wanpeng Li <kernellwp@...il.com>
Subject: [PATCH 2/3] KVM: x86: really disarm lapic timer when clearing TMICT

preemption timer only looks at tscdeadline and could inject already
disarmed timer.

Signed-off-by: Radim Krčmář <rkrcmar@...hat.com>
---
 arch/x86/kvm/lapic.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 39c1ae11ce1d..96ade848ae0b 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -1489,8 +1489,10 @@ static bool set_target_expiration(struct kvm_lapic *apic)
 	apic->lapic_timer.period = (u64)kvm_lapic_get_reg(apic, APIC_TMICT)
 		* APIC_BUS_CYCLE_NS * apic->divide_count;
 
-	if (!apic->lapic_timer.period)
+	if (!apic->lapic_timer.period) {
+		apic->lapic_timer.tscdeadline = 0;
 		return false;
+	}
 
 	limit_periodic_timer_frequency(apic);
 
-- 
2.14.2