KVM: s390: Fix ipte locking

[cascardo/linux.git] / arch / s390 / kvm / gaccess.c

diff --git a/arch/s390/kvm/gaccess.c b/arch/s390/kvm/gaccess.c
index 0f961a1..6dc0ad9 100644 (file)
--- a/arch/s390/kvm/gaccess.c
+++ b/arch/s390/kvm/gaccess.c
@@ -229,10 +229,12 @@ static void ipte_lock_simple(struct kvm_vcpu *vcpu)
                goto out;
        ic = &vcpu->kvm->arch.sca->ipte_control;
        do {
-               old = ACCESS_ONCE(*ic);
+               old = *ic;
+               barrier();
                while (old.k) {
                        cond_resched();
-                       old = ACCESS_ONCE(*ic);
+                       old = *ic;
+                       barrier();
                }
                new = old;
                new.k = 1;
@@ -251,7 +253,9 @@ static void ipte_unlock_simple(struct kvm_vcpu *vcpu)
                goto out;
        ic = &vcpu->kvm->arch.sca->ipte_control;
        do {
-               new = old = ACCESS_ONCE(*ic);
+               old = *ic;
+               barrier();
+               new = old;
                new.k = 0;
        } while (cmpxchg(&ic->val, old.val, new.val) != old.val);
        wake_up(&vcpu->kvm->arch.ipte_wq);
@@ -265,10 +269,12 @@ static void ipte_lock_siif(struct kvm_vcpu *vcpu)
 
        ic = &vcpu->kvm->arch.sca->ipte_control;
        do {
-               old = ACCESS_ONCE(*ic);
+               old = *ic;
+               barrier();
                while (old.kg) {
                        cond_resched();
-                       old = ACCESS_ONCE(*ic);
+                       old = *ic;
+                       barrier();
                }
                new = old;
                new.k = 1;
@@ -282,7 +288,9 @@ static void ipte_unlock_siif(struct kvm_vcpu *vcpu)
 
        ic = &vcpu->kvm->arch.sca->ipte_control;
        do {
-               new = old = ACCESS_ONCE(*ic);
+               old = *ic;
+               barrier();
+               new = old;
                new.kh--;
                if (!new.kh)
                        new.k = 0;