1 files changed, 50 insertions, 22 deletions

diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c
index 9979be1d7ff2..3da0e4273389 100644
--- a/arch/powerpc/kvm/booke.c
+++ b/arch/powerpc/kvm/booke.c
@@ -439,8 +439,9 @@ static void kvmppc_core_check_exceptions(struct kvm_vcpu *vcpu)
 }
 
 /* Check pending exceptions and deliver one, if possible. */
-void kvmppc_core_prepare_to_enter(struct kvm_vcpu *vcpu)
+int kvmppc_core_prepare_to_enter(struct kvm_vcpu *vcpu)
 {
+        int r = 0;
         WARN_ON_ONCE(!irqs_disabled());
 
         kvmppc_core_check_exceptions(vcpu);
@@ -451,8 +452,46 @@ void kvmppc_core_prepare_to_enter(struct kvm_vcpu *vcpu)
                 local_irq_disable();
 
                 kvmppc_set_exit_type(vcpu, EMULATED_MTMSRWE_EXITS);
-                kvmppc_core_check_exceptions(vcpu);
+                r = 1;
         };
+
+        return r;
+}
+
+/*
+ * Common checks before entering the guest world.  Call with interrupts
+ * disabled.
+ *
+ * returns !0 if a signal is pending and check_signal is true
+ */
+static int kvmppc_prepare_to_enter(struct kvm_vcpu *vcpu, bool check_signal)
+{
+        int r = 0;
+
+        WARN_ON_ONCE(!irqs_disabled());
+        while (true) {
+                if (need_resched()) {
+                        local_irq_enable();
+                        cond_resched();
+                        local_irq_disable();
+                        continue;
+                }
+
+                if (check_signal && signal_pending(current)) {
+                        r = 1;
+                        break;
+                }
+
+                if (kvmppc_core_prepare_to_enter(vcpu)) {
+                        /* interrupts got enabled in between, so we
+                           are back at square 1 */
+                        continue;
+                }
+
+                break;
+        }
+
+        return r;
 }
 
 int kvmppc_vcpu_run(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu)
@@ -470,10 +509,7 @@ int kvmppc_vcpu_run(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu)
         }
 
         local_irq_disable();
-
-        kvmppc_core_prepare_to_enter(vcpu);
-
-        if (signal_pending(current)) {
+        if (kvmppc_prepare_to_enter(vcpu, true)) {
                 kvm_run->exit_reason = KVM_EXIT_INTR;
                 ret = -EINTR;
                 goto out;
@@ -598,25 +634,21 @@ int kvmppc_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu,
 
         switch (exit_nr) {
         case BOOKE_INTERRUPT_MACHINE_CHECK:
-                kvm_resched(vcpu);
                 r = RESUME_GUEST;
                 break;
 
         case BOOKE_INTERRUPT_EXTERNAL:
                 kvmppc_account_exit(vcpu, EXT_INTR_EXITS);
-                kvm_resched(vcpu);
                 r = RESUME_GUEST;
                 break;
 
         case BOOKE_INTERRUPT_DECREMENTER:
                 kvmppc_account_exit(vcpu, DEC_EXITS);
-                kvm_resched(vcpu);
                 r = RESUME_GUEST;
                 break;
 
         case BOOKE_INTERRUPT_DOORBELL:
                 kvmppc_account_exit(vcpu, DBELL_EXITS);
-                kvm_resched(vcpu);
                 r = RESUME_GUEST;
                 break;
 
@@ -865,19 +897,15 @@ int kvmppc_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu,
                 BUG();
         }
 
+        /*
+         * To avoid clobbering exit_reason, only check for signals if we
+         * aren't already exiting to userspace for some other reason.
+         */
         local_irq_disable();
-
-        kvmppc_core_prepare_to_enter(vcpu);
-
-        if (!(r & RESUME_HOST)) {
-                /* To avoid clobbering exit_reason, only check for signals if
-                 * we aren't already exiting to userspace for some other
-                 * reason. */
-                if (signal_pending(current)) {
-                        run->exit_reason = KVM_EXIT_INTR;
-                        r = (-EINTR << 2) | RESUME_HOST | (r & RESUME_FLAG_NV);
-                        kvmppc_account_exit(vcpu, SIGNAL_EXITS);
-                }
+        if (kvmppc_prepare_to_enter(vcpu, !(r & RESUME_HOST))) {
+                run->exit_reason = KVM_EXIT_INTR;
+                r = (-EINTR << 2) | RESUME_HOST | (r & RESUME_FLAG_NV);
+                kvmppc_account_exit(vcpu, SIGNAL_EXITS);
         }
 
         return r;