linux/drivers/infiniband/hw/mlx4
Jack Morgenstein df7fba6647 IB/mlx4: Fix possible deadlock on sm_lock spinlock
The sm_lock spinlock is taken in the process context by
mlx4_ib_modify_device, and in the interrupt context by update_sm_ah,
so we need to take that spinlock with irqsave, and release it with
irqrestore.

Lockdeps reports this as follows:

    [ INFO: inconsistent lock state ]
    3.5.0+ #20 Not tainted
    inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-W} usage.
    swapper/0/0 [HC1[1]:SC0[0]:HE0:SE1] takes:
    (&(&ibdev->sm_lock)->rlock){?.+...}, at: [<ffffffffa028af1d>] update_sm_ah+0xad/0x100 [mlx4_ib]
    {HARDIRQ-ON-W} state was registered at:
      [<ffffffff810b84a0>] mark_irqflags+0x120/0x190
      [<ffffffff810b9ce7>] __lock_acquire+0x307/0x4c0
      [<ffffffff810b9f51>] lock_acquire+0xb1/0x150
      [<ffffffff815523b1>] _raw_spin_lock+0x41/0x50
      [<ffffffffa028d563>] mlx4_ib_modify_device+0x63/0x240 [mlx4_ib]
      [<ffffffffa026d1fc>] ib_modify_device+0x1c/0x20 [ib_core]
      [<ffffffffa026c353>] set_node_desc+0x83/0xc0 [ib_core]
      [<ffffffff8136a150>] dev_attr_store+0x20/0x30
      [<ffffffff81201fd6>] sysfs_write_file+0xe6/0x170
      [<ffffffff8118da38>] vfs_write+0xc8/0x190
      [<ffffffff8118dc01>] sys_write+0x51/0x90
      [<ffffffff8155b869>] system_call_fastpath+0x16/0x1b

    ...
    *** DEADLOCK ***

    1 lock held by swapper/0/0:

    stack backtrace:
    Pid: 0, comm: swapper/0 Not tainted 3.5.0+ #20
    Call Trace:
    <IRQ>  [<ffffffff810b7bea>] print_usage_bug+0x18a/0x190
    [<ffffffff810b7370>] ? print_irq_inversion_bug+0x210/0x210
    [<ffffffff810b7fb2>] mark_lock_irq+0xf2/0x280
    [<ffffffff810b8290>] mark_lock+0x150/0x240
    [<ffffffff810b84ef>] mark_irqflags+0x16f/0x190
    [<ffffffff810b9ce7>] __lock_acquire+0x307/0x4c0
    [<ffffffffa028af1d>] ? update_sm_ah+0xad/0x100 [mlx4_ib]
    [<ffffffff810b9f51>] lock_acquire+0xb1/0x150
    [<ffffffffa028af1d>] ? update_sm_ah+0xad/0x100 [mlx4_ib]
    [<ffffffff815523b1>] _raw_spin_lock+0x41/0x50
    [<ffffffffa028af1d>] ? update_sm_ah+0xad/0x100 [mlx4_ib]
    [<ffffffffa026b2fa>] ? ib_create_ah+0x1a/0x40 [ib_core]
    [<ffffffffa028af1d>] update_sm_ah+0xad/0x100 [mlx4_ib]
    [<ffffffff810c27c3>] ? is_module_address+0x23/0x30
    [<ffffffffa028b05b>] handle_port_mgmt_change_event+0xeb/0x150 [mlx4_ib]
    [<ffffffffa028c177>] mlx4_ib_event+0x117/0x160 [mlx4_ib]
    [<ffffffff81552501>] ? _raw_spin_lock_irqsave+0x61/0x70
    [<ffffffffa022718c>] mlx4_dispatch_event+0x6c/0x90 [mlx4_core]
    [<ffffffffa0221b40>] mlx4_eq_int+0x500/0x950 [mlx4_core]

Reported by: Or Gerlitz <ogerlitz@mellanox.com>
Tested-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <roland@purestorage.com>
2012-08-10 13:02:24 -07:00
..
ah.c IB/mlx4: Fix SL to 802.1Q priority-bits mapping for IBoE 2012-01-03 21:00:02 -08:00
cq.c IB/mlx4: Increase the number of vectors (EQs) available for ULPs 2012-05-18 17:04:00 -07:00
doorbell.c IB: expand ib_umem_get() prototype 2008-04-29 08:06:12 -07:00
Kconfig mlx4: Fix infiniband Kconfig dependencies. 2011-08-11 23:05:05 -07:00
mad.c IB/mlx4: Fix possible deadlock on sm_lock spinlock 2012-08-10 13:02:24 -07:00
main.c IB/mlx4: Fix possible deadlock on sm_lock spinlock 2012-08-10 13:02:24 -07:00
Makefile IB/mlx4: Add a driver Mellanox ConnectX InfiniBand adapters 2007-05-08 18:00:38 -07:00
mlx4_ib.h InfiniBand/RDMA changes for the 3.6 merge window: 2012-07-24 13:56:26 -07:00
mr.c IB/mlx4: Replace printk(KERN_yyy...) with pr_yyy(...) 2012-05-08 11:59:36 -07:00
qp.c InfiniBand/RDMA changes for the 3.6 merge window: 2012-07-24 13:56:26 -07:00
srq.c IB/mlx4: Replace printk(KERN_yyy...) with pr_yyy(...) 2012-05-08 11:59:36 -07:00
user.h mlx4: Update/add Mellanox Technologies copyright lines to mlx4 driver files 2008-07-25 10:32:52 -07:00