xen/events: switch user event channels to lateeoi model

commit c44b849cee8c3ac587da3b0980e01f77500d158c upstream.

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: Julien Grall <julien@xen.org>
Signed-off-by: Juergen Gross <jgross@suse.com>
Tested-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Wei Liu <wl@xen.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Juergen Gross 2020-09-07 15:47:29 +02:00 committed by Greg Kroah-Hartman
parent 48b533aa83
commit b7d6a66e21
1 changed files with 3 additions and 4 deletions

View File

@ -166,7 +166,6 @@ static irqreturn_t evtchn_interrupt(int irq, void *data)
"Interrupt for port %d, but apparently not enabled; per-user %p\n",
evtchn->port, u);
disable_irq_nosync(irq);
evtchn->enabled = false;
spin_lock(&u->ring_prod_lock);
@ -292,7 +291,7 @@ 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);
}
}
@ -392,8 +391,8 @@ static int evtchn_bind_to_user(struct per_user_data *u, int port)
if (rc < 0)
goto err;
rc = bind_evtchn_to_irqhandler(port, evtchn_interrupt, 0,
u->name, evtchn);
rc = bind_evtchn_to_irqhandler_lateeoi(port, evtchn_interrupt, 0,
u->name, evtchn);
if (rc < 0)
goto err;