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Date: Thu, 30 Jan 2014 14:09:02 -0800
From: Andrew Morton <akpm@linux-foundation.org>
To: David Rientjes <rientjes@google.com>
Cc: Vladimir Davydov <vdavydov@parallels.com>, mhocko@suse.cz,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] memcg: fix mutex not unlocked on
 memcg_create_kmem_cache fail path
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On Thu, 30 Jan 2014 14:04:12 -0800 (PST) David Rientjes <rientjes@google.com> wrote:

> On Thu, 30 Jan 2014, Andrew Morton wrote:
> 
> > > Yeah, it shouldn't be temporary it should be the one and only allocation.  
> > > We should construct the name in memcg_create_kmem_cache() and be done with 
> > > it.
> > 
> > Could.  That would require converting memcg_create_kmem_cache() to take 
> > a va_list and call kasprintf() on it.
> > 
> 
> Why?  We already construct the name in memcg_create_kmem_cache() 
> appropriately, we just want to avoid the kstrdup() in 
> kmem_cache_create_memcg() since it's pointless like my patch does.

oh, OK, missed that.

The problem now is that the string at kmem_cache.name is PATH_MAX
bytes, and PATH_MAX is huuuuuuuge.