[Qemu-ppc] [RFC PATCH 09/17] KVM: PPC64: booke: Hard disable interrupts when entering guest

[Mihai Caraman]

64-bit host runs with lazy interrupt disabling, so local_irq_disable() does
not disable interrupts right away and does not protect against preemption
required by __kvmppc_vcpu_run(). Define a macro for 64-bit to use
hard_irq_disable().

Signed-off-by: Mihai Caraman <address@hidden>
---
 arch/powerpc/kvm/booke.c |   14 ++++++++++----
 1 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c
index 93b48e0..db05692 100644
--- a/arch/powerpc/kvm/booke.c
+++ b/arch/powerpc/kvm/booke.c
@@ -45,6 +45,12 @@ unsigned long kvmppc_booke_handlers;
 #define VM_STAT(x) offsetof(struct kvm, stat.x), KVM_STAT_VM
 #define VCPU_STAT(x) offsetof(struct kvm_vcpu, stat.x), KVM_STAT_VCPU
 
+#ifdef CONFIG_64BIT
+#define _hard_irq_disable() hard_irq_disable()
+#else
+#define _hard_irq_disable() local_irq_disable()
+#endif
+
 struct kvm_stats_debugfs_item debugfs_entries[] = {
        { "mmio",       VCPU_STAT(mmio_exits) },
        { "dcr",        VCPU_STAT(dcr_exits) },
@@ -456,7 +462,7 @@ int kvmppc_core_prepare_to_enter(struct kvm_vcpu *vcpu)
                local_irq_enable();
                kvm_vcpu_block(vcpu);
                clear_bit(KVM_REQ_UNHALT, &vcpu->requests);
-               local_irq_disable();
+               _hard_irq_disable();
 
                kvmppc_set_exit_type(vcpu, EMULATED_MTMSRWE_EXITS);
                r = 1;
@@ -480,7 +486,7 @@ static int kvmppc_prepare_to_enter(struct kvm_vcpu *vcpu)
                if (need_resched()) {
                        local_irq_enable();
                        cond_resched();
-                       local_irq_disable();
+                       _hard_irq_disable();
                        continue;
                }
 
@@ -515,7 +521,7 @@ int kvmppc_vcpu_run(struct kvm_run *kvm_run, struct 
kvm_vcpu *vcpu)
                return -EINVAL;
        }
 
-       local_irq_disable();
+       _hard_irq_disable();
        if (kvmppc_prepare_to_enter(vcpu)) {
                kvm_run->exit_reason = KVM_EXIT_INTR;
                ret = -EINTR;
@@ -955,7 +961,7 @@ int kvmppc_handle_exit(struct kvm_run *run, struct kvm_vcpu 
*vcpu,
         * aren't already exiting to userspace for some other reason.
         */
        if (!(r & RESUME_HOST)) {
-               local_irq_disable();
+               _hard_irq_disable();
                if (kvmppc_prepare_to_enter(vcpu)) {
                        run->exit_reason = KVM_EXIT_INTR;
                        r = (-EINTR << 2) | RESUME_HOST | (r & RESUME_FLAG_NV);
-- 
1.7.4.1