Commit e6587cdb authored Dec 21, 2018 by Stefano Stabellini Committed by Boris Ostrovsky Jan 02, 2019

pvcalls-back: set -ENOTCONN in pvcalls_conn_back_read



When a connection is closing we receive on pvcalls_sk_state_change
notification. Instead of setting the connection as closed immediately
(-ENOTCONN), let's read one more time from it: pvcalls_conn_back_read
will set the connection as closed when necessary.

That way, we avoid races between pvcalls_sk_state_change and
pvcalls_back_ioworker.

Signed-off-by: Stefano Stabellini <stefanos@xilinx.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>

parent d90a1ca6

drivers/xen/pvcalls-back.c

+4 −3

Original line number	Diff line number	Diff line
		@@ -160,9 +160,10 @@ static void pvcalls_conn_back_read(void *opaque)

		/* write the data, then modify the indexes */
		virt_wmb();
		if (ret < 0)
		if (ret < 0) {
		atomic_set(&map->read, 0);
		intf->in_error = ret;
		else
		} else
		intf->in_prod = prod + ret;
		/* update the indexes, then notify the other end */
		virt_wmb();
		@@ -288,7 +289,7 @@ static void pvcalls_sk_state_change(struct sock *sock)
		return;

		intf = map->ring;
		intf->in_error = -ENOTCONN;
		atomic_inc(&map->read);
		notify_remote_via_irq(map->irq);
		}