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Date: Tue, 28 Aug 2001 12:45:41 -0300 (BRST)
From: Rik van Riel <riel@conectiva.com.br>
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To: Hugh Dickins <hugh@veritas.com>
Cc: Marcelo Tosatti <marcelo@conectiva.com.br>, Ingo Molnar <mingo@elte.hu>,
        lkml <linux-kernel@vger.kernel.org>
Subject: Re: find_get_swapcache_page() question
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On Tue, 28 Aug 2001, Hugh Dickins wrote:

> 		if (!PageSwapCache(found))
> 			BUG();
> 		if (found->mapping != &swapper_space)
> 			BUG();
> are not safe, since there may a concurrent remove_from_swap_cache(),
> either from try_to_unuse() or from Rik's new vm_swap_full() deletion.
> Those tests would be safe if the page were locked, but it's not.

vm_swap_full() is called with the page locked,
remove_from_swap_cache() also seems to want the
page locked...

Rik
-- 
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