KVM: PPC: Book3S HV P9: Fix irq disabling in tick accounting

kvmhv_run_single_vcpu() disables PMIs as well as Linux irqs,
however the tick time accounting code enables and disables irqs and
not PMIs within this region. By chance this might not actually cause
a bug, but it is clearly an incorrect use of the APIs.

Fixes: 2251fbe76395e ("KVM: PPC: Book3S HV P9: Improve mtmsrd scheduling by delaying MSR[EE] disable")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220908132545.4085849-2-npiggin@gmail.com

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 0868c015c6b0e1c92c30a18f9494adee6400d214..0f8dee6573364134a02ea793d6b4c77305ba08b0 100644 (file)
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -4634,7 +4634,7 @@ int kvmhv_run_single_vcpu(struct kvm_vcpu *vcpu, u64 time_limit,
 
        context_tracking_guest_exit();
        if (!vtime_accounting_enabled_this_cpu()) {
-               local_irq_enable();
+               powerpc_local_irq_pmu_restore(flags);
                /*
                 * Service IRQs here before vtime_account_guest_exit() so any
                 * ticks that occurred while running the guest are accounted to
@@ -4643,7 +4643,7 @@ int kvmhv_run_single_vcpu(struct kvm_vcpu *vcpu, u64 time_limit,
                 * interrupts here, which has the problem that it accounts
                 * interrupt processing overhead to the host.
                 */
-               local_irq_disable();
+               powerpc_local_irq_pmu_save(flags);
        }
        vtime_account_guest_exit();