xen/events: bind all new interdomain events to VCPU0

Commit fc087e10734a4d3e40693fc099461ec1270b3fff (xen/events: remove
unnecessary init_evtchn_cpu_bindings()) causes a regression.

The kernel-side VCPU binding was not being correctly set for newly
allocated or bound interdomain events.  In ARM guests where 2-level
events were used, this would result in no interdomain events being
handled because the kernel-side VCPU masks would all be clear.

x86 guests would work because the irq affinity was set during irq
setup and this would set the correct kernel-side VCPU binding.

Fix this by properly initializing the kernel-side VCPU binding in
bind_evtchn_to_irq().

Reported-and-tested-by: Julien Grall <julien.grall@linaro.org>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c
index 4672e00..f4a9e33 100644 (file)
--- a/drivers/xen/events/events_base.c
+++ b/drivers/xen/events/events_base.c
@@ -862,6 +862,8 @@ int bind_evtchn_to_irq(unsigned int evtchn)
                        irq = ret;
                        goto out;
                }
+               /* New interdomain events are bound to VCPU 0. */
+               bind_evtchn_to_cpu(evtchn, 0);
        } else {
                struct irq_info *info = info_for_irq(irq);
                WARN_ON(info == NULL || info->type != IRQT_EVTCHN);