From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A9E39C433E6 for ; Wed, 17 Mar 2021 20:45:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5AFB264F3B for ; Wed, 17 Mar 2021 20:45:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231920AbhCQUok (ORCPT ); Wed, 17 Mar 2021 16:44:40 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:47088 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233360AbhCQUoe (ORCPT ); Wed, 17 Mar 2021 16:44:34 -0400 Received: from pps.filterd (m0098393.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.43/8.16.0.43) with SMTP id 12HKYcci129399; Wed, 17 Mar 2021 16:44:29 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=date : from : to : cc : subject : message-id : references : mime-version : content-type : in-reply-to; s=pp1; bh=TZWvtxAEABDXhAWjElMwLqknxdMXxE+DwRpI7YG7zAE=; b=f3GN9vIXTvfPkOBe29Kswwhf71nvONnFHfjZWc1UGrjVQ+rFcr9X9Ir3J1Nhb5W76D5s 7A07d0HXnj4nH6ROCleEkcpwCPymGX+21nYaceAeuiYjNzbeqJ7o/5Jyts4t0E5rXsMK OEl1cWm3itLl43SzGviUkwOm6aIhNIhDsNhH46m6WMKrPZTpTEEVxH2xSB3/Ev9EDcLk BCABErJpgnuqyTBIiC40GsOZMTNGsUs8EYyb7NX4xyc6J73F7iKWSw2f7DBz+3U4j6ar xtt+KGRE2zt+p9vZMyJFpug8j/7rQlCh+pHaYMQYKXr2qHgDdqR53EcwjHjmFpxp1MV3 kQ== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 37bnrcp0pa-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 17 Mar 2021 16:44:28 -0400 Received: from m0098393.ppops.net (m0098393.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.43/8.16.0.43) with SMTP id 12HKYeOp129537; Wed, 17 Mar 2021 16:44:28 -0400 Received: from ppma06ams.nl.ibm.com (66.31.33a9.ip4.static.sl-reverse.com [169.51.49.102]) by mx0a-001b2d01.pphosted.com with ESMTP id 37bnrcp0nt-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 17 Mar 2021 16:44:28 -0400 Received: from pps.filterd (ppma06ams.nl.ibm.com [127.0.0.1]) by ppma06ams.nl.ibm.com (8.16.0.43/8.16.0.43) with SMTP id 12HKgXkl025562; Wed, 17 Mar 2021 20:44:25 GMT Received: from b06cxnps4076.portsmouth.uk.ibm.com (d06relay13.portsmouth.uk.ibm.com [9.149.109.198]) by ppma06ams.nl.ibm.com with ESMTP id 37b30p0yd9-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 17 Mar 2021 20:44:25 +0000 Received: from d06av26.portsmouth.uk.ibm.com (d06av26.portsmouth.uk.ibm.com [9.149.105.62]) by b06cxnps4076.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 12HKiMvN27591166 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 17 Mar 2021 20:44:23 GMT Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id DF19AAE051; Wed, 17 Mar 2021 20:44:22 +0000 (GMT) Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 67798AE057; Wed, 17 Mar 2021 20:44:22 +0000 (GMT) Received: from osiris (unknown [9.171.26.13]) by d06av26.portsmouth.uk.ibm.com (Postfix) with ESMTPS; Wed, 17 Mar 2021 20:44:22 +0000 (GMT) Date: Wed, 17 Mar 2021 21:44:21 +0100 From: Heiko Carstens To: Shakeel Butt Cc: Andrew Morton , Roman Gushchin , Johannes Weiner , Hugh Dickins , Juergen Christ , Christian Borntraeger , Vasily Gorbik , Linux MM , Linux-Next Mailing List Subject: Re: [BUG -next] "memcg: charge before adding to swapcache on swapin" broken Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.369,18.0.761 definitions=2021-03-17_11:2021-03-17,2021-03-17 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 suspectscore=0 mlxscore=0 mlxlogscore=999 malwarescore=0 bulkscore=0 clxscore=1015 priorityscore=1501 phishscore=0 lowpriorityscore=0 spamscore=0 impostorscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2103170144 Precedence: bulk List-ID: X-Mailing-List: linux-next@vger.kernel.org On Wed, Mar 17, 2021 at 08:44:14AM -0700, Shakeel Butt wrote: > > Config below. And the fun thing is that I cannot reproduce it today > > anymore with the elfutils test case - what _seems_ to be different is > > that the test suite runs much faster than yesterday evening. Usually > > an indication that there is no steal time (other guests which steal > > cpu time), which again _could_ indicate a race / lack of locking > > somewhere. > > This is kind of odd, since yesterday evening it was very reliable to > > trigger the bug :/ > > > > Thanks for the config. One question regarding swap, is it disk based > swap or zram? Swap device is a real disk. > By guests, do you mean there was another significant workload running > on the machine in parallel to the tests? That I don't know. I didn't check. I still can't reproduce with elfutils anymore, however... > If you don't mind can you try swapping01 as well. ltp's swapping01 test triggers immediately random processes being killed with SIGSEGV. I also tested with linux-next 20210316 and _only_ "memcg: charge before adding to swapcache on swapin" being reverted on top, and the problem is away - so it looks like the result of yesterday's bisect is indeed valid.