Commit c44b849c authored by Juergen Gross's avatar Juergen Gross
Browse files

xen/events: switch user event channels to lateeoi model 



Instead of disabling the irq when an event is received and enabling
it again when handled by the user process use the lateeoi model.

This is part of XSA-332.

Cc: stable@vger.kernel.org
Reported-by: default avatarJulien Grall <julien@xen.org>
Signed-off-by: default avatarJuergen Gross <jgross@suse.com>
Tested-by: default avatarStefano Stabellini <sstabellini@kernel.org>
Reviewed-by: default avatarStefano Stabellini <sstabellini@kernel.org>
Reviewed-by: default avatarJan Beulich <jbeulich@suse.com>
Reviewed-by: default avatarWei Liu <wl@xen.org>
parent c2711441

drivers/xen/evtchn.c

+3 −4
Original line number Diff line number Diff line
@@ -167,7 +167,6 @@ static irqreturn_t evtchn_interrupt(int irq, void *data) 
	     "Interrupt for port %u, but apparently not enabled; per-user %p\n",

	     evtchn->port, u);



	disable_irq_nosync(irq);

	evtchn->enabled = false;



	spin_lock(&u->ring_prod_lock);
@@ -293,7 +292,7 @@ static ssize_t evtchn_write(struct file *file, const char __user *buf, 
		evtchn = find_evtchn(u, port);

		if (evtchn && !evtchn->enabled) {

			evtchn->enabled = true;

			enable_irq(irq_from_evtchn(port));

			xen_irq_lateeoi(irq_from_evtchn(port), 0);

		}

	}
@@ -393,7 +392,7 @@ static int evtchn_bind_to_user(struct per_user_data *u, evtchn_port_t port) 
	if (rc < 0)

		goto err;



	rc = bind_evtchn_to_irqhandler(port, evtchn_interrupt, 0,

	rc = bind_evtchn_to_irqhandler_lateeoi(port, evtchn_interrupt, 0,

					       u->name, evtchn);

	if (rc < 0)

		goto err;