• Eric Dumazet's avatar
    drop_monitor: dont sleep in atomic context · bec4596b
    Eric Dumazet authored
    drop_monitor calls several sleeping functions while in atomic context.
     BUG: sleeping function called from invalid context at mm/slub.c:943
     in_atomic(): 1, irqs_disabled(): 0, pid: 2103, name: kworker/0:2
     Pid: 2103, comm: kworker/0:2 Not tainted 3.5.0-rc1+ #55
     Call Trace:
      [<ffffffff810697ca>] __might_sleep+0xca/0xf0
      [<ffffffff811345a3>] kmem_cache_alloc_node+0x1b3/0x1c0
      [<ffffffff8105578c>] ? queue_delayed_work_on+0x11c/0x130
      [<ffffffff815343fb>] __alloc_skb+0x4b/0x230
      [<ffffffffa00b0360>] ? reset_per_cpu_data+0x160/0x160 [drop_monitor]
      [<ffffffffa00b022f>] reset_per_cpu_data+0x2f/0x160 [drop_monitor]
      [<ffffffffa00b03ab>] send_dm_alert+0x4b/0xb0 [drop_monitor]
      [<ffffffff810568e0>] process_one_work+0x130/0x4c0
      [<ffffffff81058249>] worker_thread+0x159/0x360
      [<ffffffff810580f0>] ? manage_workers.isra.27+0x240/0x240
      [<ffffffff8105d403>] kthread+0x93/0xa0
      [<ffffffff816be6d4>] kernel_thread_helper+0x4/0x10
      [<ffffffff8105d370>] ? kthread_freezable_should_stop+0x80/0x80
      [<ffffffff816be6d0>] ? gs_change+0xb/0xb
    Rework the logic to call the sleeping functions in right context.
    Use standard timer/workqueue api to let system chose any cpu to perform
    the allocation and netlink send.
    Also avoid a loop if reset_per_cpu_data() cannot allocate memory :
    use mod_timer() to wait 1/10 second before next try.
    Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
    Cc: Neil Horman <nhorman@tuxdriver.com>
    Reviewed-by: default avatarNeil Horman <nhorman@tuxdriver.com>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
drop_monitor.c 9.57 KB