From 8d6c45da6da688f310bd8e9960b13efe6c72f7cf Mon Sep 17 00:00:00 2001 From: Marcelo Tosatti <mtosatti@redhat.com> Date: Thu, 23 Jul 2009 10:42:16 -0300 Subject: [PATCH 2/2] KVM: SVM: force new asid on vcpu migration If a migrated vcpu matches the asid_generation value of the target pcpu, there will be no TLB flush via TLB_CONTROL_FLUSH_ALL_ASID. The check for vcpu.cpu in pre_svm_run is meaningless since svm_vcpu_load already updated it on schedule in. Such vcpu will VMRUN with stale TLB entries. Based on original patch from Joerg Roedel (http://patchwork.kernel.org/patch/10021/) Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> (cherry picked from commit 64f3068fd4cd2de030c0859cdb4c265dcfe5382e) Bugzilla: 513394 Message-ID: <20090723134216.GD25899@amt.cnet> Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> RH-Upstream-status: backported-from-upstream Acked-by: Gleb Natapov <gleb@redhat.com> Acked-by: Juan Quintela <quintela@redhat.com> Acked-by: Glauber Costa <glommer@redhat.com> --- arch/x86/kvm/svm.c | 6 +++--- 1 files changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index f6cab53..c7dcbd1 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -710,6 +710,7 @@ static void svm_vcpu_load(struct kvm_vcpu *vcpu, int cpu) svm->vmcb->control.tsc_offset += delta; vcpu->cpu = cpu; kvm_migrate_timers(vcpu); + svm->asid_generation = 0; } for (i = 0; i < NR_HOST_SAVE_USER_MSRS; i++) @@ -962,7 +963,6 @@ static void new_asid(struct vcpu_svm *svm, struct svm_cpu_data *svm_data) svm->vmcb->control.tlb_ctl = TLB_CONTROL_FLUSH_ALL_ASID; } - svm->vcpu.cpu = svm_data->cpu; svm->asid_generation = svm_data->asid_generation; svm->vmcb->control.asid = svm_data->next_asid++; } @@ -1540,8 +1540,8 @@ static void pre_svm_run(struct vcpu_svm *svm) struct svm_cpu_data *svm_data = per_cpu(svm_data, cpu); svm->vmcb->control.tlb_ctl = TLB_CONTROL_DO_NOTHING; - if (svm->vcpu.cpu != cpu || - svm->asid_generation != svm_data->asid_generation) + /* FIXME: handle wraparound of asid_generation */ + if (svm->asid_generation != svm_data->asid_generation) new_asid(svm, svm_data); } -- 1.6.3.rc4.29.g8146