[PATCH 2/3] KVM: nVMX: Change emulated VMX-preemption timer hrtimer to absolute

Jim Mattson
2020-05-08T20:37:04Z

Prepare for migration of this hrtimer, by changing it from relative to
absolute. (I couldn't get migration to work with a relative timer.)

Signed-off-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Peter Shier <pshier@google.com>
Reviewed-by: Oliver Upton <oupton@google.com>
---
arch/x86/kvm/vmx/nested.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index 1f7fe6f47cbc..3ca792e3cd66 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -2041,7 +2041,8 @@ static void vmx_start_preemption_timer(struct kvm_vcpu *vcpu)
preemption_timeout *= 1000000;
do_div(preemption_timeout, vcpu->arch.virtual_tsc_khz);
hrtimer_start(&vmx->nested.preemption_timer,
- ns_to_ktime(preemption_timeout), HRTIMER_MODE_REL_PINNED);
+ ktime_add_ns(ktime_get(), preemption_timeout),
+ HRTIMER_MODE_ABS_PINNED);
}

static u64 nested_vmx_calc_efer(struct vcpu_vmx *vmx, struct vmcs12 *vmcs12)
@@ -4614,7 +4615,7 @@ static int enter_vmx_operation(struct kvm_vcpu *vcpu)
goto out_shadow_vmcs;

hrtimer_init(&vmx->nested.preemption_timer, CLOCK_MONOTONIC,
- HRTIMER_MODE_REL_PINNED);
+ HRTIMER_MODE_ABS_PINNED);
vmx->nested.preemption_timer.function = vmx_preemption_timer_fn;

vmx->nested.vpid02 = allocate_vpid();
--
2.26.2.645.ge9eca65c58-goog