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.
This is upstream commit c44b849cee8c3ac587da3b0980e01f77500d158c
Cc: stable@xxxxxxxxxxxxxxx
Reported-by: Julien Grall <julien@xxxxxxx>
Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
Tested-by: Stefano Stabellini <sstabellini@xxxxxxxxxx>
Reviewed-by: Stefano Stabellini <sstabellini@xxxxxxxxxx>
Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx>
Reviewed-by: Wei Liu <wl@xxxxxxx>
---
drivers/xen/evtchn.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)
diff --git a/drivers/xen/evtchn.c b/drivers/xen/evtchn.c
index 052b55a14ebc..a43930191e20 100644
--- a/drivers/xen/evtchn.c
+++ b/drivers/xen/evtchn.c
@@ -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;
--
2.26.2
