linux/drivers/net/ethernet/cisco/enic
Govindarajulu Varadarajan b6931c9ba7 enic: fix possible deadlock in enic_stop/ enic_rfs_flw_tbl_free
The following warning is shown when spinlock debug is enabled.

This occurs when enic_flow_may_expire timer function is running and
enic_stop is called on same CPU.

Fix this by using spink_lock_bh().

=================================
[ INFO: inconsistent lock state ]
3.17.0-netnext-05504-g59f35b8 #268 Not tainted
---------------------------------
inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage.
ifconfig/443 [HC0[0]:SC0[0]:HE1:SE1] takes:
 (&(&enic->rfs_h.lock)->rlock){+.?...}, at:
enic_rfs_flw_tbl_free+0x34/0xd0 [enic]
{IN-SOFTIRQ-W} state was registered at:
  [<ffffffff810a25af>] __lock_acquire+0x83f/0x21c0
  [<ffffffff810a45f2>] lock_acquire+0xa2/0xd0
  [<ffffffff814913fc>] _raw_spin_lock+0x3c/0x80
  [<ffffffffa029c3d5>] enic_flow_may_expire+0x25/0x130[enic]
  [<ffffffff810bcd07>] call_timer_fn+0x77/0x100
  [<ffffffff810bd8e3>] run_timer_softirq+0x1e3/0x270
  [<ffffffff8105f9ae>] __do_softirq+0x14e/0x280
  [<ffffffff8105fdae>] irq_exit+0x8e/0xb0
  [<ffffffff8103da0f>] smp_apic_timer_interrupt+0x3f/0x50
  [<ffffffff81493742>] apic_timer_interrupt+0x72/0x80
  [<ffffffff81018143>] default_idle+0x13/0x20
  [<ffffffff81018a6a>] arch_cpu_idle+0xa/0x10
  [<ffffffff81097676>] cpu_startup_entry+0x2c6/0x330
  [<ffffffff8103b7ad>] start_secondary+0x21d/0x290
irq event stamp: 2997
hardirqs last  enabled at (2997): [<ffffffff81491865>] _raw_spin_unlock_irqrestore+0x65/0x90
hardirqs last disabled at (2996): [<ffffffff814915e6>] _raw_spin_lock_irqsave+0x26/0x90
softirqs last  enabled at (2968): [<ffffffff813b57a3>] dev_deactivate_many+0x213/0x260
softirqs last disabled at (2966): [<ffffffff813b5783>] dev_deactivate_many+0x1f3/0x260

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&(&enic->rfs_h.lock)->rlock);
  <Interrupt>
    lock(&(&enic->rfs_h.lock)->rlock);

 *** DEADLOCK ***

Reported-by: Jan Stancek <jstancek@redhat.com>
Signed-off-by: Govindarajulu Varadarajan <_govind@gmx.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-21 15:24:25 -04:00
..
cq_desc.h
cq_enet_desc.h enic: Fix endianness bug. 2012-02-24 17:53:03 -05:00
enic_api.c enic: fix lockdep around devcmd_lock 2014-06-23 14:32:19 -07:00
enic_api.h drivers/net: enic: Add an interface for USNIC to interact with firmware 2013-08-20 13:41:01 -07:00
enic_clsf.c enic: fix possible deadlock in enic_stop/ enic_rfs_flw_tbl_free 2014-10-21 15:24:25 -04:00
enic_clsf.h enic: Add ethtool support to show classifier filters added by the driver 2014-07-21 20:22:46 -07:00
enic_dev.c enic: fix lockdep around devcmd_lock 2014-06-23 14:32:19 -07:00
enic_dev.h enic: fix lockdep around devcmd_lock 2014-06-23 14:32:19 -07:00
enic_ethtool.c enic: Add tunable_ops support for rx_copybreak 2014-09-05 12:12:20 -07:00
enic_main.c enic: implement rx_copybreak 2014-09-05 12:12:20 -07:00
enic_pp.c net: enic: slight optimization of addr compare 2013-12-31 16:48:31 -05:00
enic_pp.h enic: Add support for port profile association on a enic SRIOV VF 2011-09-27 01:10:24 -04:00
enic_res.c enic: Add Accelerated RFS support 2014-06-23 14:32:19 -07:00
enic_res.h drivers/net: enic: Adding support for Cisco Low Latency NIC 2013-08-20 13:41:01 -07:00
enic.h enic: implement rx_copybreak 2014-09-05 12:12:20 -07:00
Kconfig net: Remove bogus dependencies on INET 2012-11-19 19:13:59 -05:00
Makefile enic: devcmd for adding IP 5 tuple hardware filters 2014-06-23 14:32:19 -07:00
rq_enet_desc.h
vnic_cq.c
vnic_cq.h enic: Add support for adaptive interrupt coalescing 2014-05-21 17:04:13 -04:00
vnic_dev.c drivers/net: Convert remaining uses of pr_warning to pr_warn 2014-09-09 20:37:08 -07:00
vnic_dev.h enic: devcmd for adding IP 5 tuple hardware filters 2014-06-23 14:32:19 -07:00
vnic_devcmd.h enic: devcmd for adding IP 5 tuple hardware filters 2014-06-23 14:32:19 -07:00
vnic_enet.h enic: Add Accelerated RFS support 2014-06-23 14:32:19 -07:00
vnic_intr.c
vnic_intr.h
vnic_nic.h
vnic_resource.h
vnic_rq.c drivers/net: enic: Adding support for Cisco Low Latency NIC 2013-08-20 13:41:01 -07:00
vnic_rq.h enic: add low latency socket busy_poll support 2014-06-23 14:32:19 -07:00
vnic_rss.h
vnic_stats.h
vnic_vic.c
vnic_vic.h
vnic_wq.c drivers/net: enic: Adding support for Cisco Low Latency NIC 2013-08-20 13:41:01 -07:00
vnic_wq.h drivers/net: enic: Adding support for Cisco Low Latency NIC 2013-08-20 13:41:01 -07:00
wq_enet_desc.h