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Date: Fri, 17 Oct 2008 13:17:17 +0100 (BST)
From: Hugh Dickins <hugh@veritas.com>
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To: Bodo Eggert <7eggert@gmx.de>
cc: David Newall <davidn@davidnewall.com>,
       Peter Zijlstra <peterz@infradead.org>, Peter Cordes <peter@cordes.ca>,
       linux-kernel@vger.kernel.org, Christoph Hellwig <hch@infradead.org>,
       linux-mm <linux-mm@kvack.org>
Subject: Re: no way to swapoff a deleted swap file?
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On Fri, 17 Oct 2008, Bodo Eggert wrote:
> 
> Somebody might want their swapfiles to have zero links,
> _and_ the possibility of doing swapoff.

You're right, they might, and it's not an unreasonable wish.
But we've not supported it in the past, and I still don't
think it's worth adding special kernel support for it now.

> If you can do it by keeping some fds open to let
> /proc/pid/fd point to the files, I think it's OK.

I've a very strong aversion to adding strange code to abuse the
/proc/<pid>/fd space of some random kernel thread - a "kswapd"
because its name contains the substring "swap"?

Hugh
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