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>
parent
d10845fc
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