linux-kernel - [PATCH 2/4] KVM: x86: initialize kvmclock

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Date:   Thu,  1 Sep 2016 17:26:13 +0200
From:   Paolo Bonzini <pbonzini@...hat.com>
To:     linux-kernel@...r.kernel.org, kvm@...r.kernel.org
Cc:     peterhornyack@...gle.com, rkrcmar@...hat.com, den@...nvz.org,
        rkagan@...tuozzo.com
Subject: [PATCH 2/4] KVM: x86: initialize kvmclock_offset

Make the guest's kvmclock count up from zero, not from the host boot
time.  The guest cannot rely on that anyway because it changes on
migration, the numbers are easier on the eye and finally it matches the
desired semantics of the Hyper-V time reference counter.

Signed-off-by: Paolo Bonzini <pbonzini@...hat.com>
---
 arch/x86/kvm/x86.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 65974dd0565f..b5853b86b67d 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -7774,6 +7774,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 	mutex_init(&kvm->arch.apic_map_lock);
 	spin_lock_init(&kvm->arch.pvclock_gtod_sync_lock);
 
+	kvm->arch.kvmclock_offset = -get_kernel_ns();
 	pvclock_update_vm_gtod_copy(kvm);
 
 	INIT_DELAYED_WORK(&kvm->arch.kvmclock_update_work, kvmclock_update_fn);
-- 
1.8.3.1