[PATCH 2/2] net-sysfs: Use rtnl_trylock in wireless sysfs methods.

The wireless sysfs methods like the rest of the networking sysfs
methods are removed with the rtnl_lock held and block until
the existing methods stop executing.  So use rtnl_trylock
and restart_syscall so that the code continues to work.

Signed-off-by: Eric W. Biederman <redacted>
---
 net/core/net-sysfs.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c
index fbc1c74..099c753 100644
--- a/net/core/net-sysfs.c
+++ b/net/core/net-sysfs.c

@@ -410,7 +410,8 @@ static ssize_t wireless_show(struct device *d, char *buf,
 	const struct iw_statistics *iw;
 	ssize_t ret = -EINVAL;
 
-	rtnl_lock();
+	if (!rtnl_trylock())
+		return restart_syscall();
 	if (dev_isalive(dev)) {
 		iw = get_wireless_stats(dev);
 		if (iw)

-- 
1.6.5.2.143.g8cc62