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
diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c
index 7bbfd58..d7e361f 100644
--- a/drivers/xen/events/events_base.c
+++ b/drivers/xen/events/events_base.c
@@ -642,6 +642,9 @@
}
info->eoi_time = 0;
+
+ /* is_active hasn't been reset yet, do it now. */
+ smp_store_release(&info->is_active, 0);
do_unmask(info, EVT_MASK_REASON_EOI_PENDING);
}
@@ -811,6 +814,7 @@
BUG();
}
+/* Not called for lateeoi events. */
static void event_handler_exit(struct irq_info *info)
{
smp_store_release(&info->is_active, 0);
@@ -1883,7 +1887,12 @@
if (VALID_EVTCHN(evtchn)) {
do_mask(info, EVT_MASK_REASON_EOI_PENDING);
- event_handler_exit(info);
+ /*
+ * Don't call event_handler_exit().
+ * Need to keep is_active non-zero in order to ignore re-raised
+ * events after cpu affinity changes while a lateeoi is pending.
+ */
+ clear_evtchn(evtchn);
}
}
