From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail190.messagelabs.com (mail190.messagelabs.com [216.82.249.51]) by kanga.kvack.org (Postfix) with SMTP id 6247B6B0047 for ; Sat, 4 Sep 2010 08:29:54 -0400 (EDT) Date: Sat, 4 Sep 2010 14:29:49 +0200 From: Andrea Arcangeli Subject: Re: [PATCH] fix swapin race condition Message-ID: <20100904122949.GJ16761@random.random> References: <20100903153958.GC16761@random.random> <20100903130259.b7dd8da5.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20100903130259.b7dd8da5.akpm@linux-foundation.org> Sender: owner-linux-mm@kvack.org To: Andrew Morton Cc: Hugh Dickins , linux-mm@kvack.org List-ID: On Fri, Sep 03, 2010 at 01:02:59PM -0700, Andrew Morton wrote: > On Fri, 3 Sep 2010 17:39:58 +0200 > Andrea Arcangeli wrote: > > > The pte_same check is reliable only if the swap entry remains pinned > > (by the page lock on swapcache). We've also to ensure the swapcache > > isn't removed before we take the lock as try_to_free_swap won't care > > about the page pin. > > What were the end-user-observeable effects of this bug? I found it by code review only. > Do we think the fix should be backported into earlier kernels? Considering I didn't see user-observable effects it's up to you. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org