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

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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: 2251fbe763 ("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
This commit is contained in:
Nicholas Piggin 2022-09-08 23:25:42 +10:00 committed by Michael Ellerman
parent bc91c04bff
commit c953f7500b
1 changed files with 2 additions and 2 deletions
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4
arch/powerpc/kvm/book3s_hv.c
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@ -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();