diff options
Diffstat (limited to 'arch/powerpc/kvm/book3s_xive.c')
-rw-r--r-- | arch/powerpc/kvm/book3s_xive.c | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/arch/powerpc/kvm/book3s_xive.c b/arch/powerpc/kvm/book3s_xive.c index 586867e46e51..591bfb4bfd0f 100644 --- a/arch/powerpc/kvm/book3s_xive.c +++ b/arch/powerpc/kvm/book3s_xive.c @@ -166,6 +166,9 @@ static irqreturn_t xive_esc_irq(int irq, void *data) */ vcpu->arch.xive_esc_on = false; + /* This orders xive_esc_on = false vs. subsequent stale_p = true */ + smp_wmb(); /* goes with smp_mb() in cleanup_single_escalation */ + return IRQ_HANDLED; } @@ -1119,6 +1122,31 @@ void kvmppc_xive_disable_vcpu_interrupts(struct kvm_vcpu *vcpu) vcpu->arch.xive_esc_raddr = 0; } +/* + * In single escalation mode, the escalation interrupt is marked so + * that EOI doesn't re-enable it, but just sets the stale_p flag to + * indicate that the P bit has already been dealt with. However, the + * assembly code that enters the guest sets PQ to 00 without clearing + * stale_p (because it has no easy way to address it). Hence we have + * to adjust stale_p before shutting down the interrupt. + */ +void xive_cleanup_single_escalation(struct kvm_vcpu *vcpu, + struct kvmppc_xive_vcpu *xc, int irq) +{ + struct irq_data *d = irq_get_irq_data(irq); + struct xive_irq_data *xd = irq_data_get_irq_handler_data(d); + + /* + * This slightly odd sequence gives the right result + * (i.e. stale_p set if xive_esc_on is false) even if + * we race with xive_esc_irq() and xive_irq_eoi(). + */ + xd->stale_p = false; + smp_mb(); /* paired with smb_wmb in xive_esc_irq */ + if (!vcpu->arch.xive_esc_on) + xd->stale_p = true; +} + void kvmppc_xive_cleanup_vcpu(struct kvm_vcpu *vcpu) { struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu; @@ -1143,6 +1171,9 @@ void kvmppc_xive_cleanup_vcpu(struct kvm_vcpu *vcpu) /* Free escalations */ for (i = 0; i < KVMPPC_XIVE_Q_COUNT; i++) { if (xc->esc_virq[i]) { + if (xc->xive->single_escalation) + xive_cleanup_single_escalation(vcpu, xc, + xc->esc_virq[i]); free_irq(xc->esc_virq[i], vcpu); irq_dispose_mapping(xc->esc_virq[i]); kfree(xc->esc_virq_names[i]); |