屋漏偏逢連夜雨

所以就連系統也要來跟我亂, poll的時候會有soft lockup?!

[43278797.150000] BUG: soft lockup detected on CPU#0! [43278797.150000] <c0147e3c> softlockup_tick+0x9c/0xf0 <c012aff1> update_process_times+0x31/0x80 [43278797.150000] <c0113cd5> smp_apic_timer_interrupt+0x55/0x60 <c0103acc> apic_timer_interrupt+0x1c/0x24 [43278797.150000] <c02ad971> udp_v4_lookup_longway+0x61/0x110 <c02af633> udp_rcv+0x283/0x570 [43278797.150000] <c014ff62> __alloc_pages+0x52/0x300 <c028eced> ip_local_deliver+0x10d/0x2e0 [43278797.150000] <c028e99c> ip_rcv+0x2ac/0x4f0 <c026fc37> netif_receive_skb+0x207/0x2e0 [43278797.150000] <c026bda5> __alloc_skb+0x55/0x110 <f08d6e35> rtl8139_poll+0x2e5/0x4e0 [8139too] [43278797.150000] <f08d6cdd> rtl8139_poll+0x18d/0x4e0 [8139too] <c025d9b3> i8042_interrupt+0x1e3/0x230 [43278797.150000] <c027185b> net_rx_action+0xbb/0x190 <c0126aa2> __do_softirq+0x72/0xe0 [43278797.150000] <c0126b45> do_softirq+0x35/0x40 <c01055ae> do_IRQ+0x1e/0x30 [43278797.150000] <c0103a3e> common_interrupt+0x1a/0x20 <c02d8e39> _spin_unlock_irqrestore+0x9/0x10 [43278797.150000] <c017d6de> free_poll_entry+0xe/0x20 <c017d730> poll_freewait+0x40/0x60 [43278797.150000] <c017d890> do_sys_poll+0x140/0x400 <c017e600> __pollwait+0x0/0xf0 [43278797.150000] <c011b170> default_wake_function+0x0/0x10 <c011b170> default_wake_function+0x0/0x10 [43278797.150000] <c011b170> default_wake_function+0x0/0x10 <c011b170> default_wake_function+0x0/0x10 [43278797.150000] <c011b170> default_wake_function+0x0/0x10 <c011b170> default_wake_function+0x0/0x10 [43278797.150000] <c011b170> default_wake_function+0x0/0x10 <c011b170> default_wake_function+0x0/0x10 [43278797.150000] <c011b170> default_wake_function+0x0/0x10 <c011b170> default_wake_function+0x0/0x10 [43278797.150000] <c011b170> default_wake_function+0x0/0x10 <c011b170> default_wake_function+0x0/0x10 [43278797.150000] <c011b170> default_wake_function+0x0/0x10 <c011b170> default_wake_function+0x0/0x10 [43278797.150000] <c011b170> default_wake_function+0x0/0x10 <c011b170> default_wake_function+0x0/0x10 [43278797.150000] <c011b170> default_wake_function+0x0/0x10 <c011b170> default_wake_function+0x0/0x10 [43278797.150000] <c011b170> default_wake_function+0x0/0x10 <c011b170> default_wake_function+0x0/0x10 [43278797.150000] <c017db8c> sys_poll+0x3c/0x60 <c0102f93> sysenter_past_esp+0x54/0x75

講這麼多, 啊這是什麼?

Say Y here to enable the kernel to detect "soft lockups", which are bugs that cause the kernel to loop in kernel mode for more than 10 seconds, without giving other tasks a chance to run. When a soft-lockup is detected, the kernel will print the current stack trace (which you should report), but the system will stay locked up. This feature has negligible overhead.