[1/4] kvm/powerpc/e500mc: fix tlb invalidation on cpu migration

Submitted by Alexander Graf on April 11, 2013, 3:34 p.m.

Details

Message ID 1365694492-25108-2-git-send-email-agraf@suse.de
State New
Headers show

Commit Message

Alexander Graf April 11, 2013, 3:34 p.m.
From: Scott Wood <scottwood@freescale.com>

The existing check handles the case where we've migrated to a different
core than we last ran on, but it doesn't handle the case where we're
still on the same cpu we last ran on, but some other vcpu has run on
this cpu in the meantime.

Without this, guest segfaults (and other misbehavior) have been seen in
smp guests.

Cc: stable@vger.kernel.org # 3.8.x
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
---
 arch/powerpc/kvm/e500mc.c |    7 ++++++-
 1 files changed, 6 insertions(+), 1 deletions(-)

Patch hide | download patch | download mbox

diff --git a/arch/powerpc/kvm/e500mc.c b/arch/powerpc/kvm/e500mc.c
index 1f89d26..2f4baa0 100644
--- a/arch/powerpc/kvm/e500mc.c
+++ b/arch/powerpc/kvm/e500mc.c
@@ -108,6 +108,8 @@  void kvmppc_mmu_msr_notify(struct kvm_vcpu *vcpu, u32 old_msr)
 {
 }
 
+static DEFINE_PER_CPU(struct kvm_vcpu *, last_vcpu_on_cpu);
+
 void kvmppc_core_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 {
 	struct kvmppc_vcpu_e500 *vcpu_e500 = to_e500(vcpu);
@@ -136,8 +138,11 @@  void kvmppc_core_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 	mtspr(SPRN_GDEAR, vcpu->arch.shared->dar);
 	mtspr(SPRN_GESR, vcpu->arch.shared->esr);
 
-	if (vcpu->arch.oldpir != mfspr(SPRN_PIR))
+	if (vcpu->arch.oldpir != mfspr(SPRN_PIR) ||
+	    __get_cpu_var(last_vcpu_on_cpu) != vcpu) {
 		kvmppc_e500_tlbil_all(vcpu_e500);
+		__get_cpu_var(last_vcpu_on_cpu) = vcpu;
+	}
 
 	kvmppc_load_guest_fp(vcpu);
 }