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Merge tag 'for-linus-5.13b-rc8-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen fix from Juergen Gross: "A fix for a regression introduced in 5.12: when migrating an irq related to a Xen user event to another cpu, a race might result in a WARN() triggering" * tag 'for-linus-5.13b-rc8-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen/events: reset active flag for lateeoi events later
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drivers/xen/events/events_base.c

Lines changed: 10 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -642,6 +642,9 @@ static void xen_irq_lateeoi_locked(struct irq_info *info, bool spurious)
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}
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info->eoi_time = 0;
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/* is_active hasn't been reset yet, do it now. */
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smp_store_release(&info->is_active, 0);
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do_unmask(info, EVT_MASK_REASON_EOI_PENDING);
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}
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@@ -811,6 +814,7 @@ static void xen_evtchn_close(evtchn_port_t port)
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BUG();
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}
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/* Not called for lateeoi events. */
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static void event_handler_exit(struct irq_info *info)
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{
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smp_store_release(&info->is_active, 0);
@@ -1883,7 +1887,12 @@ static void lateeoi_ack_dynirq(struct irq_data *data)
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if (VALID_EVTCHN(evtchn)) {
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do_mask(info, EVT_MASK_REASON_EOI_PENDING);
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event_handler_exit(info);
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/*
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* Don't call event_handler_exit().
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* Need to keep is_active non-zero in order to ignore re-raised
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* events after cpu affinity changes while a lateeoi is pending.
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*/
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clear_evtchn(evtchn);
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}
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}
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