From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Subject: Re: bad return value in __mutex_lock_check_stamp
Date: Sun, 15 Dec 2013 16:10:11 +0100
Message-ID: <52ADC653.7090005@linutronix.de>
References: <20131215144047.GB32756@opentech.at>
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Cc: linux-rt-users@vger.kernel.org
To: Nicholas Mc Guire <der.herr@hofr.at>
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On 12/15/2013 03:40 PM, Nicholas Mc Guire wrote:
> 
> Bad return value in _mutex_lock_check_stamp - this problem only would show 
> up with 3.12.1 rt4 applied but CONFIG_PREEMPT_RT_FULL not enabled 
> currently it would be returning what ever vprintk_emit ended up with 
> (atleast on x86), which probably is not the intended behavior. Added a
> return 0; as in the case with CONFIG_PREEMPT_RT_FULL enabled.

Interesting. How do you trigger this? This BUG()-only function should
get completely removed by gcc because
- ctx argument should be always NULL
- BUG() has unreachable() so gcc knows it does not return.

Sebastian