On kernel 3.17 I see a random complete stall during emerge/compile code wich occupies all 8 cpu threads.
This is the log I can see after rebooting a complete locked machine: Oct 9 20:45:19 localhost kernel: INFO: rcu_preempt detected stalls on CPUs/tasks: { 7} (detected by 0, t=60002 jiffies, g=221162, c=221161, q=0) Oct 9 20:45:19 localhost kernel: Task dump for CPU 7: Oct 9 20:45:19 localhost kernel: cc1plus R running task 0 12992 12991 0x00080008 Oct 9 20:45:19 localhost kernel: ffffffff8109947d ffffffff810984e4 ffff88022fbd1c80 00000000000000a9 Oct 9 20:45:19 localhost kernel: 0000000000000006 00007f927dcef000 ffff880226bee540 ffff8800c386ff58 Oct 9 20:45:19 localhost kernel: ffff8802225317e0 ffffffff8106aac9 ffff880226bee5a0 0000000000000002 Oct 9 20:45:19 localhost kernel: Call Trace: Oct 9 20:45:19 localhost kernel: [<ffffffff8109947d>] ? pick_next_entity+0x9d/0x180 Oct 9 20:45:19 localhost kernel: [<ffffffff810984e4>] ? update_curr+0x74/0xd0 Oct 9 20:45:19 localhost kernel: [<ffffffff8106aac9>] ? __do_page_fault+0x199/0x450 Oct 9 20:45:19 localhost kernel: [<ffffffff8160d4af>] ? __schedule+0x63f/0x820 Oct 9 20:45:19 localhost kernel: [<ffffffff810a37a1>] ? cpuacct_account_field+0x11/0x60 Oct 9 20:45:19 localhost kernel: [<ffffffff81097923>] ? vtime_user_enter+0x23/0x40 Oct 9 20:45:19 localhost kernel: [<ffffffff810a37a1>] ? cpuacct_account_field+0x11/0x60 Oct 9 20:45:19 localhost kernel: [<ffffffff810a37a1>] ? cpuacct_account_field+0x11/0x60 Oct 9 20:45:19 localhost kernel: [<ffffffff81097923>] ? vtime_user_enter+0x23/0x40 Oct 9 20:45:19 localhost kernel: [<ffffffff816125d2>] ? page_fault+0x22/0x30 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/