On 02/18/2013 04:24 PM, Thomas Gleixner wrote: > On Mon, 18 Feb 2013, Srivatsa S. Bhat wrote: >> Lockup observed while running this patchset, with CPU_IDLE and INTEL_IDLE turned >> on in the .config: >> >> smpboot: CPU 1 is now offline >> Kernel panic - not syncing: Watchdog detected hard LOCKUP on cpu 11 >> Pid: 0, comm: swapper/11 Not tainted 3.8.0-rc7+stpmch13-1 #8 >> Call Trace: >> [<ffffffff812aba1e>] do_raw_spin_lock+0x7e/0x150 >> [<ffffffff815a64c1>] _raw_spin_lock_irqsave+0x61/0x70 >> [<ffffffff810c0758>] ? clockevents_notify+0x28/0x150 >> [<ffffffff815a6d37>] ? _raw_spin_unlock_irqrestore+0x77/0x80 >> [<ffffffff810c0758>] clockevents_notify+0x28/0x150 >> [<ffffffff8130459f>] intel_idle+0xaf/0xe0 >> [<ffffffff81472ee0>] ? disable_cpuidle+0x20/0x20 >> [<ffffffff81472ef9>] cpuidle_enter+0x19/0x20 >> [<ffffffff814734c1>] cpuidle_wrap_enter+0x41/0xa0 >> [<ffffffff81473530>] cpuidle_enter_tk+0x10/0x20 >> [<ffffffff81472f17>] cpuidle_enter_state+0x17/0x50 >> [<ffffffff81473899>] cpuidle_idle_call+0xd9/0x290 >> [<ffffffff810203d5>] cpu_idle+0xe5/0x140 >> [<ffffffff8159c603>] start_secondary+0xdd/0xdf > >> BUG: spinlock lockup suspected on CPU#2, migration/2/19 >> lock: clockevents_lock+0x0/0x40, .magic: dead4ead, .owner: swapper/8/0, .owner_cpu: 8 > > Unfortunately there is no back trace for cpu8. Yes :-( I had run this several times hoping to get a backtrace on the lock-holder, expecting trigger_all_cpu_backtrace() to get it right at least once. But I hadn't succeeded even once. > That's probably caused > by the watchdog -> panic setting. > Oh, ok.. > So we have no idea why cpu2 and 11 get stuck on the clockevents_lock > and without that information it's impossible to decode. > But thankfully, the issue seems to have been resolved by the diff I posted in my previous mail, along with the fixes related to memory barriers. Regards, Srivatsa S. Bhat -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
