From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f71.google.com (mail-pg0-f71.google.com [74.125.83.71]) by kanga.kvack.org (Postfix) with ESMTP id EE7CD6B0297 for ; Mon, 24 Apr 2017 09:16:06 -0400 (EDT) Received: by mail-pg0-f71.google.com with SMTP id k14so13395704pga.5 for ; Mon, 24 Apr 2017 06:16:06 -0700 (PDT) Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com. [148.163.156.1]) by mx.google.com with ESMTPS id y12si18930398pgo.307.2017.04.24.06.16.06 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 24 Apr 2017 06:16:06 -0700 (PDT) Received: from pps.filterd (m0098409.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.20/8.16.0.20) with SMTP id v3ODEn4U134945 for ; Mon, 24 Apr 2017 09:16:05 -0400 Received: from e06smtp14.uk.ibm.com (e06smtp14.uk.ibm.com [195.75.94.110]) by mx0a-001b2d01.pphosted.com with ESMTP id 2a02g3c7g1-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Mon, 24 Apr 2017 09:16:05 -0400 Received: from localhost by e06smtp14.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 24 Apr 2017 14:16:03 +0100 Subject: Re: [RFC 1/2] mm: Uncharge poisoned pages References: <1492680362-24941-1-git-send-email-ldufour@linux.vnet.ibm.com> <1492680362-24941-2-git-send-email-ldufour@linux.vnet.ibm.com> <20170424090530.GA31900@hori1.linux.bs1.fc.nec.co.jp> From: Laurent Dufour Date: Mon, 24 Apr 2017 15:15:59 +0200 MIME-Version: 1.0 In-Reply-To: <20170424090530.GA31900@hori1.linux.bs1.fc.nec.co.jp> Content-Type: text/plain; charset=iso-2022-jp Content-Transfer-Encoding: 7bit Message-Id: Sender: owner-linux-mm@kvack.org List-ID: To: Naoya Horiguchi Cc: "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , "akpm@linux-foundation.org" On 24/04/2017 11:05, Naoya Horiguchi wrote: > On Thu, Apr 20, 2017 at 11:26:01AM +0200, Laurent Dufour wrote: >> When page are poisoned, they should be uncharged from the root memory >> cgroup. > > Could you include some information about what problem this patch tries > to solve? > # I know that you already explain it in patch 0/2, so you can simply > # copy from it. Thanks for the review, I will add the BUG's output in the next version. > >> >> Signed-off-by: Laurent Dufour >> --- >> mm/memory-failure.c | 1 + >> 1 file changed, 1 insertion(+) >> >> diff --git a/mm/memory-failure.c b/mm/memory-failure.c >> index 27f7210e7fab..00bd39d3d4cb 100644 >> --- a/mm/memory-failure.c >> +++ b/mm/memory-failure.c >> @@ -530,6 +530,7 @@ static const char * const action_page_types[] = { >> static int delete_from_lru_cache(struct page *p) >> { >> if (!isolate_lru_page(p)) { >> + memcg_kmem_uncharge(p, 0); > > This function is supposed to be called with if (memcg_kmem_enabled()) check, > so could you do like below? > > + if (memcg_kmem_enabled()) > + memcg_kmem_uncharge(p, 0); > > > And I feel that we can call this function outside if (!isolate_lru_page(p)) > block, because isolate_lru_page could fail and then the error page is left > incompletely isolated. Such error page has PageHWPoison set, so I guess that > the reported bug still triggers on such case. I move the call to memcg_kmem_uncharge() outside if (!isolate_lru_page(p)) and it seems to work as well. I'll wait a bit for any other review to come and I'll send a new version. Thanks, Laurent. -- 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