diff --git a/xen/arch/x86/irq.c b/xen/arch/x86/irq.c index 2eac2de0b4..b1387cf6c9 100644 --- a/xen/arch/x86/irq.c +++ b/xen/arch/x86/irq.c @@ -2539,7 +2539,7 @@ void fixup_irqs(const cpumask_t *mask, bool verbose) for ( irq = 0; irq < nr_irqs; irq++ ) { bool break_affinity = false, set_affinity = true; - unsigned int vector; + unsigned int vector, cpu = smp_processor_id(); cpumask_t *affinity = this_cpu(scratch_cpumask); if ( irq == 2 ) @@ -2582,6 +2582,33 @@ void fixup_irqs(const cpumask_t *mask, bool verbose) affinity); } + if ( desc->arch.move_in_progress && + /* + * Only attempt to adjust the mask if the current CPU is going + * offline, otherwise the whole system is going down and leaving + * stale data in the masks is fine. + */ + !cpu_online(cpu) && + cpumask_test_cpu(cpu, desc->arch.old_cpu_mask) ) + { + /* + * This CPU is going offline, remove it from ->arch.old_cpu_mask + * and possibly release the old vector if the old mask becomes + * empty. + * + * Note cleaning ->arch.old_cpu_mask is required if the CPU is + * brought offline and then online again, as when re-onlined the + * per-cpu vector table will no longer have ->arch.old_vector + * setup, and hence ->arch.old_cpu_mask would be stale. + */ + cpumask_clear_cpu(cpu, desc->arch.old_cpu_mask); + if ( cpumask_empty(desc->arch.old_cpu_mask) ) + { + desc->arch.move_in_progress = 0; + release_old_vec(desc); + } + } + /* * Avoid shuffling the interrupt around as long as current target CPUs * are a subset of the input mask. What fixup_irqs() cares about is