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From: Nicolai Stange <nicstange@gmail.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Nicolai Stange <nicstange@gmail.com>, Juergen Gross <jgross@suse.com>,
        Ingo Molnar <mingo@kernel.org>, Thomas Gleixner <tglx@linutronix.de>,
        Davidlohr Bueso <dave@stgolabs.net>,
        Richard Weinberger <richard@nod.at>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] smp: smp_call_on_cpu(): use INIT_WORK_ONSTACK() for automatic work_struct
References: <20160922181758.3449-1-nicstange@gmail.com>
        <20160922184415.GB5012@twins.programming.kicks-ass.net>
Date: Thu, 22 Sep 2016 21:15:52 +0200
In-Reply-To: <20160922184415.GB5012@twins.programming.kicks-ass.net> (Peter
        Zijlstra's message of "Thu, 22 Sep 2016 20:44:15 +0200")
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Peter Zijlstra <peterz@infradead.org> writes:

> On Thu, Sep 22, 2016 at 08:17:58PM +0200, Nicolai Stange wrote:
>> This new warning
>> 
>>   INFO: trying to register non-static key.
>>   the code is fine but needs lockdep annotation.
>>   turning off the locking correctness validator.
>>   CPU: 0 PID: 82 Comm: kworker/0:1 Not tainted 4.8.0-rc6+ #360
>>   Hardware name: Dell Inc. Latitude E6540/0725FP, BIOS A10 06/26/2014
>>   Workqueue: events smp_call_on_cpu_callback
>
> https://lkml.kernel.org/r/tip-8db549491c4a3ce9e1d509b75f78516e497f48ec@git.kernel.org


Ah, thanks for letting me know.

One minor question regarding your patch though: it hasn't got a
destroy_work_on_stack(). Isn't one needed because of
  INIT_WORK_ONSTACK() -> __INIT_WORK() -> __init_work() ->
  debug_object_init_on_stack() ?
At least work_on_cpu() destroys its local work_struct that way...


Thanks,

Nicolai