From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with SMTP id CD7CE6B0078 for ; Tue, 10 Nov 2009 21:42:12 -0500 (EST) Received: from m4.gw.fujitsu.co.jp ([10.0.50.74]) by fgwmail6.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id nAB2gANn007517 for (envelope-from kosaki.motohiro@jp.fujitsu.com); Wed, 11 Nov 2009 11:42:10 +0900 Received: from smail (m4 [127.0.0.1]) by outgoing.m4.gw.fujitsu.co.jp (Postfix) with ESMTP id 091EA45DE60 for ; Wed, 11 Nov 2009 11:42:10 +0900 (JST) Received: from s4.gw.fujitsu.co.jp (s4.gw.fujitsu.co.jp [10.0.50.94]) by m4.gw.fujitsu.co.jp (Postfix) with ESMTP id B385545DE70 for ; Wed, 11 Nov 2009 11:42:09 +0900 (JST) Received: from s4.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s4.gw.fujitsu.co.jp (Postfix) with ESMTP id 707E0E1800A for ; Wed, 11 Nov 2009 11:42:09 +0900 (JST) Received: from ml13.s.css.fujitsu.com (ml13.s.css.fujitsu.com [10.249.87.103]) by s4.gw.fujitsu.co.jp (Postfix) with ESMTP id F132C1DB803A for ; Wed, 11 Nov 2009 11:42:05 +0900 (JST) From: KOSAKI Motohiro Subject: Re: [PATCH 6/6] mm: sigbus instead of abusing oom In-Reply-To: <20091111113719.589e61d7.kamezawa.hiroyu@jp.fujitsu.com> References: <20091111113719.589e61d7.kamezawa.hiroyu@jp.fujitsu.com> Message-Id: <20091111114119.FD53.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Date: Wed, 11 Nov 2009 11:42:04 +0900 (JST) Sender: owner-linux-mm@kvack.org To: KAMEZAWA Hiroyuki Cc: kosaki.motohiro@jp.fujitsu.com, Hugh Dickins , Andrew Morton , Izik Eidus , Andrea Arcangeli , Minchan Kim , Andi Kleen , Wu Fengguang , linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: > On Tue, 10 Nov 2009 22:06:49 +0000 (GMT) > Hugh Dickins wrote: > > > When do_nonlinear_fault() realizes that the page table must have been > > corrupted for it to have been called, it does print_bad_pte() and > > returns ... VM_FAULT_OOM, which is hard to understand. > > > > It made some sense when I did it for 2.6.15, when do_page_fault() > > just killed the current process; but nowadays it lets the OOM killer > > decide who to kill - so page table corruption in one process would > > be liable to kill another. > > > > Change it to return VM_FAULT_SIGBUS instead: that doesn't guarantee > > that the process will be killed, but is good enough for such a rare > > abnormality, accompanied as it is by the "BUG: Bad page map" message. > > > > And recent HWPOISON work has copied that code into do_swap_page(), > > when it finds an impossible swap entry: fix that to VM_FAULT_SIGBUS too. > > > > Signed-off-by: Hugh Dickins > > Thank you ! > Reviewed-by: KAMEZAWA Hiroyuki Thank you, me too. Reviewed-by: KOSAKI Motohiro -- 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