From mboxrd@z Thu Jan  1 00:00:00 1970
Date: Tue, 21 Apr 2015 18:06:26 +0200
From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
Message-ID: <20150421160625.GX7109@hermes.click-hack.org>
References: <E1Yka0Q-00008c-Jh@sd-51317.xenomai.org>
 <20150421152715.GV7109@hermes.click-hack.org>
 <5536751A.6080609@siemens.com>
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Subject: Re: [Xenomai] [Xenomai-git] Jan Kiszka : lib/cobalt: Rework minimum
 stack size enforcement
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To: Jan Kiszka <jan.kiszka@siemens.com>
Cc: xenomai-git@xenomai.org, xenomai@xenomai.org

On Tue, Apr 21, 2015 at 06:04:42PM +0200, Jan Kiszka wrote:
> On 2015-04-21 17:27, Gilles Chanteperdrix wrote:
> > On Tue, Apr 21, 2015 at 05:22:34PM +0200, git repository hosting wrote:
> >> +COBALT_IMPL(int, pthread_attr_setstack, (pthread_attr_t *attr, void *stackaddr,
> >> +					 size_t stacksize))
> >> +{
> >> +	if (stacksize < COBALT_STACKSIZE_MIN)
> >> +		return -EINVAL;
> >> +	return __STD(pthread_attr_setstack)(attr, stackaddr, stacksize);
> >> +}
> > 
> > As I said, there is no reason for Xenomai to enforce a task size
> > larger than PTHREAD_STACK_MIN. This breaks POSIX compliance, and is
> > useless.
> 
> Then we should not use printf & Co. from any trampoline function, e.g.
> vxworks/taskLib.c:task_trampoline. I only tried with a local skin, but I
> bet the issue is reproducible with that one.
> 
> For that reason, I went down the conservative path.

The path you took breaks compatibility with POSIX. On a compliant
system, pthread_attr_setstacksize(attr, PTHREAD_STACK_MIN) is not
supposed to return an error.

-- 
					    Gilles.