diff options
author | Erez Shitrit <erezsh@mellanox.com> | 2017-08-17 15:50:50 +0300 |
---|---|---|
committer | Doug Ledford <dledford@redhat.com> | 2017-08-24 23:31:08 +0300 |
commit | 69956d83267e29e38cda7d506c4085932789fef2 (patch) | |
tree | 19f14834c67b6e6a19e83be6474478c865f0046e /drivers/infiniband/ulp/ipoib/ipoib_main.c | |
parent | f9bfea992e7d7557c40a58e8536ad8c6f177de25 (diff) | |
download | linux-69956d83267e29e38cda7d506c4085932789fef2.tar.xz |
IB/ipoib: Sync between remove_one to sysfs calls that use rtnl_lock
In order to avoid deadlock between sysfs functions (like create/delete
child) and remove_one (both of them are using the sysfs lock and
rtnl_lock) the driver will use a state mutex for sync.
That will fix traces as the following:
schedule+0x3e/0x90
kernfs_drain+0x75/0xf0
? wait_woken+0x90/0x90
__kernfs_remove+0x12e/0x1c0
kernfs_remove+0x25/0x40
sysfs_remove_dir+0x57/0x90
kobject_del+0x22/0x60
device_del+0x195/0x230
pm_runtime_set_memalloc_noio+0xac/0xf0
netdev_unregister_kobject+0x71/0x80
rollback_registered_many+0x205/0x2f0
rollback_registered+0x31/0x40
unregister_netdevice_queue+0x58/0xb0
unregister_netdev+0x20/0x30
ipoib_remove_one+0xb7/0x240 [ib_ipoib]
ib_unregister_device+0xbc/0x1b0 [ib_core]
ib_unregister_mad_agent+0x29/0x30 [ib_core]
mlx4_ib_remove+0x67/0x280 [mlx4_ib]
INFO: task echo:24082 blocked for more than 120 seconds.
Tainted: G OE 4.1.12-37.5.1.el6uek.x86_64 #2
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this
message.
Call Trace:
schedule+0x3e/0x90
schedule_preempt_disabled+0xe/0x10
__mutex_lock_slowpath+0x95/0x110
? _rcu_barrier+0x177/0x220
mutex_lock+0x23/0x40
rtnl_lock+0x15/0x20
netdev_run_todo+0x81/0x1f0
rtnl_unlock+0xe/0x10
ipoib_vlan_delete+0x12f/0x1c0 [ib_ipoib]
delete_child+0x69/0x80 [ib_ipoib]
dev_attr_store+0x20/0x30
sysfs_kf_write+0x41/0x50
Signed-off-by: Erez Shitrit <erezsh@mellanox.com>
Reviewed-by: Alex Vesker <valex@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Diffstat (limited to 'drivers/infiniband/ulp/ipoib/ipoib_main.c')
-rw-r--r-- | drivers/infiniband/ulp/ipoib/ipoib_main.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_main.c b/drivers/infiniband/ulp/ipoib/ipoib_main.c index 344e8d3d47bd..5f143445daa9 100644 --- a/drivers/infiniband/ulp/ipoib/ipoib_main.c +++ b/drivers/infiniband/ulp/ipoib/ipoib_main.c @@ -1878,6 +1878,7 @@ static void ipoib_build_priv(struct net_device *dev) spin_lock_init(&priv->lock); init_rwsem(&priv->vlan_rwsem); mutex_init(&priv->mcast_mutex); + mutex_init(&priv->sysfs_mutex); INIT_LIST_HEAD(&priv->path_list); INIT_LIST_HEAD(&priv->child_intfs); @@ -2329,7 +2330,11 @@ static void ipoib_remove_one(struct ib_device *device, void *client_data) cancel_delayed_work(&priv->neigh_reap_task); flush_workqueue(priv->wq); + /* Wrap rtnl_lock/unlock with mutex to protect sysfs calls */ + mutex_lock(&priv->sysfs_mutex); unregister_netdev(priv->dev); + mutex_unlock(&priv->sysfs_mutex); + rn->free_rdma_netdev(priv->dev); list_for_each_entry_safe(cpriv, tcpriv, &priv->child_intfs, list) |