3.16.72-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: YueHaibing <yuehaibing@xxxxxxxxxx> commit a3e23f719f5c4a38ffb3d30c8d7632a4ed8ccd9e upstream. In netdev_queue_add_kobject and rx_queue_add_kobject, if sysfs_create_group failed, kobject_put will call netdev_queue_release to decrease dev refcont, however dev_hold has not be called. So we will see this while unregistering dev: unregister_netdevice: waiting for bcsh0 to become free. Usage count = -1 Reported-by: Hulk Robot <hulkci@xxxxxxxxxx> Fixes: d0d668371679 ("net: don't decrement kobj reference count on init failure") Signed-off-by: YueHaibing <yuehaibing@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx> --- net/core/net-sysfs.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/net/core/net-sysfs.c +++ b/net/core/net-sysfs.c @@ -788,6 +788,8 @@ static int rx_queue_add_kobject(struct n if (error) return error; + dev_hold(queue->dev); + if (net->sysfs_rx_queue_group) { error = sysfs_create_group(kobj, net->sysfs_rx_queue_group); if (error) { @@ -797,7 +799,6 @@ static int rx_queue_add_kobject(struct n } kobject_uevent(kobj, KOBJ_ADD); - dev_hold(queue->dev); return error; } @@ -1146,6 +1147,8 @@ static int netdev_queue_add_kobject(stru if (error) return error; + dev_hold(queue->dev); + #ifdef CONFIG_BQL error = sysfs_create_group(kobj, &dql_group); if (error) { @@ -1155,7 +1158,6 @@ static int netdev_queue_add_kobject(stru #endif kobject_uevent(kobj, KOBJ_ADD); - dev_hold(queue->dev); return 0; }