[PATCH 2/2] pvcalls-front: wait for other operations to return when release passive sockets

From: Stefano Stabellini
Date: Mon Feb 05 2018 - 17:52:07 EST


Passive sockets can have ongoing operations on them, specifically, we
have two wait_event_interruptable calls in pvcalls_front_accept.

Add two wake_up calls in pvcalls_front_release, then wait for the
potential waiters to return and release the sock_mapping refcount.

Signed-off-by: Stefano Stabellini <stefano@xxxxxxxxxxx>
---
drivers/xen/pvcalls-front.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/drivers/xen/pvcalls-front.c b/drivers/xen/pvcalls-front.c
index 164d3ad..d32cac5 100644
--- a/drivers/xen/pvcalls-front.c
+++ b/drivers/xen/pvcalls-front.c
@@ -1017,6 +1017,12 @@ int pvcalls_front_release(struct socket *sock)

pvcalls_front_free_map(bedata, map);
} else {
+ wake_up(&bedata->inflight_req);
+ wake_up(&map->passive.inflight_accept_req);
+
+ while (atomic_read(&map->refcount) > 1)
+ cpu_relax();
+
spin_lock(&bedata->socket_lock);
list_del(&map->list);
spin_unlock(&bedata->socket_lock);
--
1.9.1