diff options
author | Haggai Eran <haggaie@mellanox.com> | 2015-07-07 17:45:13 +0300 |
---|---|---|
committer | Doug Ledford <dledford@redhat.com> | 2015-07-14 13:20:12 -0400 |
commit | 8b7cce0dae956b329d09099f8739821936cf7c0f (patch) | |
tree | 255b75ae43adcb94c269eebc76d70bc9ab6bc556 /drivers | |
parent | 31b57b87fddf547bf3e98306b41bc82e111396fa (diff) | |
download | linux-8b7cce0dae956b329d09099f8739821936cf7c0f.tar.bz2 |
IB/ipoib: Prevent lockdep warning in __ipoib_ib_dev_flush
__ipoib_ib_dev_flush calls itself recursively on child devices, and lockdep
complains about locking vlan_rwsem twice (see below). Use down_read_nested
instead of down_read to prevent the warning.
=============================================
[ INFO: possible recursive locking detected ]
4.1.0-rc4+ #36 Tainted: G O
---------------------------------------------
kworker/u20:2/261 is trying to acquire lock:
(&priv->vlan_rwsem){.+.+..}, at: [<ffffffffa0791e2a>] __ipoib_ib_dev_flush+0x3a/0x2b0 [ib_ipoib]
but task is already holding lock:
(&priv->vlan_rwsem){.+.+..}, at: [<ffffffffa0791e2a>] __ipoib_ib_dev_flush+0x3a/0x2b0 [ib_ipoib]
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&priv->vlan_rwsem);
lock(&priv->vlan_rwsem);
*** DEADLOCK ***
May be due to missing lock nesting notation
3 locks held by kworker/u20:2/261:
#0: ("%s""ipoib_flush"){.+.+..}, at: [<ffffffff810827cc>] process_one_work+0x15c/0x760
#1: ((&priv->flush_heavy)){+.+...}, at: [<ffffffff810827cc>] process_one_work+0x15c/0x760
#2: (&priv->vlan_rwsem){.+.+..}, at: [<ffffffffa0791e2a>] __ipoib_ib_dev_flush+0x3a/0x2b0 [ib_ipoib]
stack backtrace:
CPU: 3 PID: 261 Comm: kworker/u20:2 Tainted: G O 4.1.0-rc4+ #36
Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2007
Workqueue: ipoib_flush ipoib_ib_dev_flush_heavy [ib_ipoib]
ffff8801c6c54790 ffff8801c9927af8 ffffffff81665238 0000000000000001
ffffffff825b5b30 ffff8801c9927bd8 ffffffff810bba51 ffff880100000000
ffffffff00000001 ffff880100000001 ffff8801c6c55428 ffff8801c6c54790
Call Trace:
[<ffffffff81665238>] dump_stack+0x4f/0x6f
[<ffffffff810bba51>] __lock_acquire+0x741/0x1820
[<ffffffff810bcbf8>] lock_acquire+0xc8/0x240
[<ffffffffa0791e2a>] ? __ipoib_ib_dev_flush+0x3a/0x2b0 [ib_ipoib]
[<ffffffff81669d2c>] down_read+0x4c/0x70
[<ffffffffa0791e2a>] ? __ipoib_ib_dev_flush+0x3a/0x2b0 [ib_ipoib]
[<ffffffffa0791e2a>] __ipoib_ib_dev_flush+0x3a/0x2b0 [ib_ipoib]
[<ffffffffa0791e4a>] __ipoib_ib_dev_flush+0x5a/0x2b0 [ib_ipoib]
[<ffffffffa07920ba>] ipoib_ib_dev_flush_heavy+0x1a/0x20 [ib_ipoib]
[<ffffffff81082871>] process_one_work+0x201/0x760
[<ffffffff810827cc>] ? process_one_work+0x15c/0x760
[<ffffffff81082ef0>] worker_thread+0x120/0x4d0
[<ffffffff81082dd0>] ? process_one_work+0x760/0x760
[<ffffffff81082dd0>] ? process_one_work+0x760/0x760
[<ffffffff81088b7e>] kthread+0xfe/0x120
[<ffffffff81088a80>] ? __init_kthread_worker+0x70/0x70
[<ffffffff8166c6e2>] ret_from_fork+0x42/0x70
[<ffffffff81088a80>] ? __init_kthread_worker+0x70/0x70
Signed-off-by: Haggai Eran <haggaie@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/infiniband/ulp/ipoib/ipoib_ib.c | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_ib.c b/drivers/infiniband/ulp/ipoib/ipoib_ib.c index 63b92cbb29ad..058150ff5aa1 100644 --- a/drivers/infiniband/ulp/ipoib/ipoib_ib.c +++ b/drivers/infiniband/ulp/ipoib/ipoib_ib.c @@ -985,20 +985,21 @@ static inline int update_child_pkey(struct ipoib_dev_priv *priv) } static void __ipoib_ib_dev_flush(struct ipoib_dev_priv *priv, - enum ipoib_flush_level level) + enum ipoib_flush_level level, + int nesting) { struct ipoib_dev_priv *cpriv; struct net_device *dev = priv->dev; int result; - down_read(&priv->vlan_rwsem); + down_read_nested(&priv->vlan_rwsem, nesting); /* * Flush any child interfaces too -- they might be up even if * the parent is down. */ list_for_each_entry(cpriv, &priv->child_intfs, list) - __ipoib_ib_dev_flush(cpriv, level); + __ipoib_ib_dev_flush(cpriv, level, nesting + 1); up_read(&priv->vlan_rwsem); @@ -1076,7 +1077,7 @@ void ipoib_ib_dev_flush_light(struct work_struct *work) struct ipoib_dev_priv *priv = container_of(work, struct ipoib_dev_priv, flush_light); - __ipoib_ib_dev_flush(priv, IPOIB_FLUSH_LIGHT); + __ipoib_ib_dev_flush(priv, IPOIB_FLUSH_LIGHT, 0); } void ipoib_ib_dev_flush_normal(struct work_struct *work) @@ -1084,7 +1085,7 @@ void ipoib_ib_dev_flush_normal(struct work_struct *work) struct ipoib_dev_priv *priv = container_of(work, struct ipoib_dev_priv, flush_normal); - __ipoib_ib_dev_flush(priv, IPOIB_FLUSH_NORMAL); + __ipoib_ib_dev_flush(priv, IPOIB_FLUSH_NORMAL, 0); } void ipoib_ib_dev_flush_heavy(struct work_struct *work) @@ -1092,7 +1093,7 @@ void ipoib_ib_dev_flush_heavy(struct work_struct *work) struct ipoib_dev_priv *priv = container_of(work, struct ipoib_dev_priv, flush_heavy); - __ipoib_ib_dev_flush(priv, IPOIB_FLUSH_HEAVY); + __ipoib_ib_dev_flush(priv, IPOIB_FLUSH_HEAVY, 0); } void ipoib_ib_dev_cleanup(struct net_device *dev) |