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From: Rusty Russell <rusty@rustcorp.com.au>
To: Peter Zijlstra <peterz@infradead.org>,
        Fengguang Wu <fengguang.wu@intel.com>
Cc: x86@kernel.org, LKML <linux-kernel@vger.kernel.org>, lkp@01.org
Subject: Re: [microcode/load_module] WARNING: CPU: 0 PID: 1444 at kernel/sched/core.c:7094 __might_sleep+0x51/0x16f()
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Date: Thu, 07 Aug 2014 21:26:15 +0930
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Peter Zijlstra <peterz@infradead.org> writes:
> On Wed, Aug 06, 2014 at 05:12:24AM +0800, Fengguang Wu wrote:
>> Greetings,
>> 
>> Here is a microcode/load_module error triggered by debug check commit
>> 64c2181bc433b17f04da8fe8592aa83cceac9606 ("sched: Debug nested
>> sleeps"):

Hmm, google lead me to that.  Yuck, that's subtle.

> Cc: Rusty Russell <rusty@rustcorp.com.au>
> Reported-by: Fengguang Wu <fengguang.wu@intel.com>
> Signed-off-by: Peter Zijlstra <peterz@infradead.org>
> Link: http://lkml.kernel.org/n/tip-xtd4qlahotb7ar4bmo9lapz8@git.kernel.org
> ---
>  kernel/module.c |   26 ++++++++++++++++++++++++--
>  1 file changed, 24 insertions(+), 2 deletions(-)
>
> --- a/kernel/module.c
> +++ b/kernel/module.c
> @@ -3094,6 +3094,28 @@ static int may_init_module(void)
>  	return 0;
>  }
>  
> +int wait_finished_loading(struct module *mod)
> +{

Is this something we can generalize?  At least needs a comment on
why we don't just use the normal wait_event_interruptible...

Cheers,
Rusty.