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>
Acked-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 71510e0..b1f658a 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -711,6 +711,7 @@
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++)
@@ -1031,7 +1032,6 @@
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++;
}
@@ -2300,8 +2300,8 @@
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);
}