From 0f127d12e44c13d2f90e5c613490e70ddb1a5e08 Mon Sep 17 00:00:00 2001 From: Lan Tianyu Date: Sun, 13 Mar 2016 11:10:29 +0800 Subject: [PATCH] KVM/x86: update the comment of memory barrier in the vcpu_enter_guest() The barrier also orders the write to mode from any reads to the page tables done and so update the comment. Signed-off-by: Lan Tianyu Signed-off-by: Paolo Bonzini --- arch/x86/kvm/x86.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 98ae1fb9fd66..e260ccbc8f55 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -6596,8 +6596,12 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu) srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx); - /* We should set ->mode before check ->requests, - * see the comment in make_all_cpus_request. + /* + * We should set ->mode before check ->requests, + * Please see the comment in kvm_make_all_cpus_request. + * This also orders the write to mode from any reads + * to the page tables done while the VCPU is running. + * Please see the comment in kvm_flush_remote_tlbs. */ smp_mb__after_srcu_read_unlock(); -- 2.45.2