From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kalle Valo Subject: [PATCH] net: fix rtnl even race in register_netdevice() Date: Fri, 29 Apr 2011 20:26:34 +0300 Message-ID: <20110429172634.27130.25375.stgit@x201> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: linux-wireless-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Return-path: Sender: linux-wireless-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: netdev.vger.kernel.org From: Kalle Valo There's a race in register_netdevice so that the rtnl event is sent before the device is actually ready. This was visible with flimflam, chrome os connection manager: 00:21:35 roska flimflamd[2598]: src/udev.c:add_net_device() 00:21:35 roska flimflamd[2598]: connman_inet_ifname: SIOCGIFNAME(index 4): No such device 00:21:45 roska flimflamd[2598]: src/rtnl.c:rtnl_message() buf 0xbfefda3c len 1004 00:21:45 roska flimflamd[2598]: src/rtnl.c:rtnl_message() NEWLINK len 1004 type 16 flags 0x0000 seq 0 So the kobject is visible in udev before the device is ready. (ignore the 10 s delay, I added that to reproduce the issue easily) The issue is reported here: https://bugzilla.kernel.org/show_bug.cgi?id=15606 The fix is to call netdev_register_kobject() after the device is added to the list. Signed-off-by: Kalle Valo --- net/core/dev.c | 10 +++++----- 1 files changed, 5 insertions(+), 5 deletions(-) diff --git a/net/core/dev.c b/net/core/dev.c index 956d3b0..f2afbe6 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -5425,11 +5425,6 @@ int register_netdevice(struct net_device *dev) if (ret) goto err_uninit; - ret = netdev_register_kobject(dev); - if (ret) - goto err_uninit; - dev->reg_state = NETREG_REGISTERED;