From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-1108014-1516780012-2-10311234474770755729 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.25, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES en, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='US', FromHeader='com', MailFrom='org', XOriginatingCountry='UNK' X-Spam-charsets: plain='windows-1252' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: stable-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1516780012; b=BvYpOq40cd5y4Sl9wQOeT3RfT6zH5Hmfq7ntRosX1sUul+9 bkZ6hXhHoprQrtBj8RgufNf1V1Df229KGbJe71a+nHJKzs3Azuk2mCmhfIvrt1Bi jBCt05PEO5n4GtAcsJPKc6jRp1Piw/LyioEOSoHXdv3TpXXCU0VSN3KBOCC8AKw2 w4sMLRcHZTOVY8vNL0nQ/CS714vip9nN8Tal1i9kpOtu29J2k16Xsqroh85czvH2 c3gNDnTToWqP4/XI0Z06ksCuFpxrd6dR+GxU9MGioGKH/BWUikualfxwq7icJ7E1 okKIykLH+GwmZZZlXB4g7kmFxoC72hEFq4X/s9A== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=subject:to:references:cc:from:message-id :date:mime-version:in-reply-to:content-type :content-transfer-encoding:sender:list-id; s=arctest; t= 1516780012; bh=G/i6Qw6zvzpB47q7OuZ9XXZHyFCQnJI3vnWl5SUwKJo=; b=Y 5XPjhPCeJ/eqRa07O/THkaUNgTvExTBhiMKguIAhhs72Aa1opQ7m/YFhdfeoko93 C2OT29tu/frBVjyWdPbJij9+C4o+glsUhGI1xZ8hb3aCdesRH2/0YExQ0RHCSI0+ sf2CqSS+AFblF6VIP3Tlrb45mBh9O8AwUbGsAmbRD+G6zV4S1iIEdaunvrBK9VSW 17HB8ZZe7mpAd4DXLax5p3XVEauQf+oelbO9GHs3tWoos7X7J+yMmswQIM1cGgyN 5P84Hp8WWKZJbmA5vCLV5D/oRQsYJCSsAYuxytohnYttKeBG9E7WPrHoQqgYPzL3 GEs9v4dDrD9SsN7uUe1Ag== ARC-Authentication-Results: i=1; mx6.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=huawei.com; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=huawei.com header.result=pass header_is_org_domain=yes Authentication-Results: mx6.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=huawei.com; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=huawei.com header.result=pass header_is_org_domain=yes Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751422AbeAXHqs (ORCPT ); Wed, 24 Jan 2018 02:46:48 -0500 Received: from szxga06-in.huawei.com ([45.249.212.32]:37885 "EHLO huawei.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1751399AbeAXHqr (ORCPT ); Wed, 24 Jan 2018 02:46:47 -0500 Subject: Re: [PATCH AUTOSEL for 4.14 078/100] kmemleak: add scheduling point to kmemleak_scan() To: Sasha Levin , "linux-kernel@vger.kernel.org" , "stable@vger.kernel.org" References: <20180124041414.32065-1-alexander.levin@microsoft.com> <20180124041414.32065-78-alexander.levin@microsoft.com> CC: Michal Hocko , Andrew Morton , Linus Torvalds From: Yisheng Xie Message-ID: Date: Wed, 24 Jan 2018 15:46:27 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.1.0 MIME-Version: 1.0 In-Reply-To: <20180124041414.32065-78-alexander.levin@microsoft.com> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.177.29.40] X-CFilter-Loop: Reflected Sender: stable-owner@vger.kernel.org X-Mailing-List: stable@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: Hi Sasha, There is a fix patch for this patch: 13ab183 mm/kmemleak.c: make cond_resched() rate-limiting more efficient So if this patch is backported to stable, maybe the above patch is also need to be backported too. Thanks Yisheng On 2018/1/24 12:15, Sasha Levin wrote: > From: Yisheng Xie > > [ Upstream commit bde5f6bc68db51128f875a756e9082a6c6ff7b4c ] > > kmemleak_scan() will scan struct page for each node and it can be really > large and resulting in a soft lockup. We have seen a soft lockup when > do scan while compile kernel: > > watchdog: BUG: soft lockup - CPU#53 stuck for 22s! [bash:10287] > [...] > Call Trace: > kmemleak_scan+0x21a/0x4c0 > kmemleak_write+0x312/0x350 > full_proxy_write+0x5a/0xa0 > __vfs_write+0x33/0x150 > vfs_write+0xad/0x1a0 > SyS_write+0x52/0xc0 > do_syscall_64+0x61/0x1a0 > entry_SYSCALL64_slow_path+0x25/0x25 > > Fix this by adding cond_resched every MAX_SCAN_SIZE. > > Link: http://lkml.kernel.org/r/1511439788-20099-1-git-send-email-xieyisheng1@huawei.com > Signed-off-by: Yisheng Xie > Suggested-by: Catalin Marinas > Acked-by: Catalin Marinas > Cc: Michal Hocko > Signed-off-by: Andrew Morton > Signed-off-by: Linus Torvalds > Signed-off-by: Sasha Levin > --- > mm/kmemleak.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/mm/kmemleak.c b/mm/kmemleak.c > index 7780cd83a495..a1ba553816eb 100644 > --- a/mm/kmemleak.c > +++ b/mm/kmemleak.c > @@ -1532,6 +1532,8 @@ static void kmemleak_scan(void) > if (page_count(page) == 0) > continue; > scan_block(page, page + 1, NULL); > + if (!(pfn % (MAX_SCAN_SIZE / sizeof(*page)))) > + cond_resched(); > } > } > put_online_mems(); >