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Date: Thu, 30 Jan 2014 14:13:18 -0800 (PST)
From: David Rientjes <rientjes@google.com>
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To: Andrew Morton <akpm@linux-foundation.org>
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, Andrew Morton wrote:

> > 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.
> 

It always was.  Google uses pretty long memcg names (although admittedly 
not as long as PATH_MAX!) and it hasn't caused any problem with 
/proc/slabinfo or slabtop(1).