Message-ID: <1370968655.3252.49.camel@edumazet-glaptop>
Subject: Re: [PATCH] slab: prevent warnings when allocating with __GFP_NOWARN
From: Eric Dumazet <eric.dumazet@gmail.com>
To: Sasha Levin <sasha.levin@oracle.com>
Cc: Christoph Lameter <cl@gentwo.org>, Pekka Enberg <penberg@kernel.org>,
        "linux-mm@kvack.org" <linux-mm@kvack.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        LKML <linux-kernel@vger.kernel.org>
Date: Tue, 11 Jun 2013 09:37:35 -0700
In-Reply-To: <51B74E28.4070906@oracle.com>
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On Tue, 2013-06-11 at 12:19 -0400, Sasha Levin wrote:

> It might be, but you need CAP_SYS_RESOURCE to go into the dangerous
> zone (>pipe_max_size).
> 
> So if root (or someone with that cap) wants to go there, as Rusty says:
> "Root asked, we do."

Yes and no : adding a test to select vmalloc()/vfree() instead of
kmalloc()/kfree() will slow down regular users asking 32 pages in their
pipe.

If there is no _sensible_ use for large pipes even for root, please do
not bloat the code just because we can.


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