From mboxrd@z Thu Jan  1 00:00:00 1970
From: =?ISO-8859-1?Q?Roger_Pau_Monn=E9?= <roger.pau@citrix.com>
Subject: Re: [PATCH] xenstore: set READ_THREAD_STACKSIZE to a
	sane value
Date: Wed, 12 Mar 2014 11:27:30 +0100
Message-ID: <53203692.9000607@citrix.com>
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To: Ian Jackson <Ian.Jackson@eu.citrix.com>
Cc: Ian Campbell <Ian.Campbell@citrix.com>, xen-devel@lists.xen.org
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On 11/03/14 17:52, Ian Jackson wrote:
> Roger Pau Monn=E9 writes ("Re: [PATCH] xenstore: set READ_THREAD_STACKSIZ=
E to a sane value"):
>> On 11/03/14 17:25, Ian Jackson wrote:
>>> Well, actually, a malloc works, doesn't it ?
>>
>> No, actually a malloc with PTHREAD_STACK_MIN doesn't work, this sample =

>> example program fails in the same way:
> =

> Wow.  I'm sure that can't be intentional.

According to
http://pubs.opengroup.org/onlinepubs/7908799/xsh/limits.h.html (or at
least that's how I read it), it shouldn't be assumed that
PTHREAD_STACK_MIN will be set to a value that allows using libc calls,
the standard even says it's valid to set it to 0.

So I think the proposed patch (or a variation of it), is the right
solution, we shouldn't rely on PTHREAD_STACK_MIN being set to a sane
value. IMHO the only thing we should use PTHREAD_STACK_MIN for is to
check that the value we are passing to pthread_attr_setstacksize is valid.