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From: Marcelo Tosatti <mtosatti@redhat.com>
To: kvm <kvm@vger.kernel.org>
Cc: Avi Kivity <avi@redhat.com>
Subject: KVM: use proper hrtimer function to retrieve expiration time
Date: Thu, 8 Oct 2009 10:55:03 -0300	[thread overview]
Message-ID: <20091008135503.GA4502@amt.cnet> (raw)


hrtimer->base can be temporarily NULL due to racing hrtimer_start.
See switch_hrtimer_base/lock_hrtimer_base.

Use hrtimer_get_remaining which is robust against it.

CC: stable@kernel.org
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

diff --git a/arch/x86/kvm/i8254.c b/arch/x86/kvm/i8254.c
index b857ca3..fab7440 100644
--- a/arch/x86/kvm/i8254.c
+++ b/arch/x86/kvm/i8254.c
@@ -116,7 +116,7 @@ static s64 __kpit_elapsed(struct kvm *kvm)
 	 * itself with the initial count and continues counting
 	 * from there.
 	 */
-	remaining = hrtimer_expires_remaining(&ps->pit_timer.timer);
+	remaining = hrtimer_get_remaining(&ps->pit_timer.timer);
 	elapsed = ps->pit_timer.period - ktime_to_ns(remaining);
 	elapsed = mod_64(elapsed, ps->pit_timer.period);
 
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 9c8f901..94aa315 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -515,7 +515,7 @@ static u32 apic_get_tmcct(struct kvm_lapic *apic)
 	if (apic_get_reg(apic, APIC_TMICT) == 0)
 		return 0;
 
-	remaining = hrtimer_expires_remaining(&apic->lapic_timer.timer);
+	remaining = hrtimer_get_remaining(&apic->lapic_timer.timer);
 	if (ktime_to_ns(remaining) < 0)
 		remaining = ktime_set(0, 0);
 


             reply	other threads:[~2009-10-08 13:55 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-10-08 13:55 Marcelo Tosatti [this message]
2009-10-08 14:16 ` KVM: use proper hrtimer function to retrieve expiration time Avi Kivity

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