Re: [PATCH v7 2/2] x86/apic: x2apic write eoi msr notrace

[Wanpeng Li]

2016-11-03 5:10 GMT+08:00 Borislav Petkov <bp@xxxxxxxxx>:
> On Mon, Oct 31, 2016 at 09:37:02AM +0800, Wanpeng Li wrote:
>> From: Wanpeng Li <wanpeng.li@xxxxxxxxxxx>
>>
>> | RCU used illegally from idle CPU!
>> | rcu_scheduler_active = 1, debug_locks = 0
>> | RCU used illegally from extended quiescent state!
>> | no locks held by swapper/1/0.
>> |
>> |  [<ffffffff9d492b95>] do_trace_write_msr+0x135/0x140
>> |  [<ffffffff9d06f860>] native_write_msr+0x20/0x30
>> |  [<ffffffff9d065fad>] native_apic_msr_eoi_write+0x1d/0x30
>> |  [<ffffffff9d05bd1d>] smp_reschedule_interrupt+0x1d/0x30
>> |  [<ffffffff9d8daec6>] reschedule_interrupt+0x96/0xa0
>
> Please remove the text between [] and the offsets after "+..." - those
> are useless in a commit message.
>
>> Reschedule interrupt may be called in cpu idle state. This causes lockdep
>
> s/cpu/CPU/
>
>> check warning above.
>>
>> As Peterz pointed out:
>>
>> | So now we're making a very frequent interrupt slower because of debug
>> | code.
>> |
>> | The thing is, many many smp_reschedule_interrupt() invocations don't
>> | actually execute anything much at all and are only send to tickle the
>
> s/send/sent/

I will send a new version to clean it up.

Regards,
Wanpeng Li