[PATCH 4.19 13/13] xen/events: fix setting irq affinity

From: Greg Kroah-Hartman
Date: Thu Apr 15 2021 - 11:07:48 EST


From: Juergen Gross <jgross@xxxxxxxx>

The backport of upstream patch 25da4618af240fbec61 ("xen/events: don't
unmask an event channel when an eoi is pending") introduced a
regression for stable kernels 5.10 and older: setting IRQ affinity for
IRQs related to interdomain events would no longer work, as moving the
IRQ to its new cpu was not included in the irq_ack callback for those
events.

Fix that by adding the needed call.

Note that kernels 5.11 and later don't need the explicit moving of the
IRQ to the target cpu in the irq_ack callback, due to a rework of the
affinity setting in kernel 5.11.

Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/xen/events/events_base.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/xen/events/events_base.c
+++ b/drivers/xen/events/events_base.c
@@ -1782,7 +1782,7 @@ static void lateeoi_ack_dynirq(struct ir

if (VALID_EVTCHN(evtchn)) {
do_mask(info, EVT_MASK_REASON_EOI_PENDING);
- event_handler_exit(info);
+ ack_dynirq(data);
}
}

@@ -1793,7 +1793,7 @@ static void lateeoi_mask_ack_dynirq(stru

if (VALID_EVTCHN(evtchn)) {
do_mask(info, EVT_MASK_REASON_EXPLICIT);
- event_handler_exit(info);
+ ack_dynirq(data);
}
}