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

[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.

Signed-off-by: Scott Wood <scottwood@freescale.com>
---
This seems to have been the cause of the userspace segfaults I was
seeing (the other TLB patches I posted are still needed as well).

 arch/powerpc/kvm/e500mc.c |    6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/kvm/e500mc.c b/arch/powerpc/kvm/e500mc.c
index 1f89d26..8637689 100644
--- a/arch/powerpc/kvm/e500mc.c
+++ b/arch/powerpc/kvm/e500mc.c
@@ -111,6 +111,7 @@ void kvmppc_mmu_msr_notify(struct kvm_vcpu *vcpu, u32 old_msr)
 void kvmppc_core_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 {
 	struct kvmppc_vcpu_e500 *vcpu_e500 = to_e500(vcpu);
+	static struct kvm_vcpu *last_vcpu_on_cpu[NR_CPUS];
 
 	kvmppc_booke_vcpu_load(vcpu, cpu);
 
@@ -136,8 +137,11 @@ 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) ||
+	    last_vcpu_on_cpu[smp_processor_id()] != vcpu) {
 		kvmppc_e500_tlbil_all(vcpu_e500);
+		last_vcpu_on_cpu[smp_processor_id()] = vcpu;
+	}
 
 	kvmppc_load_guest_fp(vcpu);
 }
-- 
1.7.9.5