From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ed1-f70.google.com (mail-ed1-f70.google.com [209.85.208.70]) by kanga.kvack.org (Postfix) with ESMTP id 9A5546B0003 for ; Sun, 4 Nov 2018 04:16:24 -0500 (EST) Received: by mail-ed1-f70.google.com with SMTP id y23-v6so3471211eds.12 for ; Sun, 04 Nov 2018 01:16:24 -0800 (PST) Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com. [148.163.158.5]) by mx.google.com with ESMTPS id f27-v6si4333563ede.346.2018.11.04.01.16.22 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sun, 04 Nov 2018 01:16:23 -0800 (PST) Received: from pps.filterd (m0098421.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id wA498jWi030516 for ; Sun, 4 Nov 2018 04:16:21 -0500 Received: from e06smtp02.uk.ibm.com (e06smtp02.uk.ibm.com [195.75.94.98]) by mx0a-001b2d01.pphosted.com with ESMTP id 2nhrvdgbe0-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Sun, 04 Nov 2018 04:16:21 -0500 Received: from localhost by e06smtp02.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Sun, 4 Nov 2018 09:16:19 -0000 Date: Sun, 4 Nov 2018 11:16:12 +0200 From: Mike Rapoport Subject: Re: Will the recent memory leak fixes be backported to longterm kernels? References: <20181102005816.GA10297@tower.DHCP.thefacebook.com> <20181102160122.GH194472@sasha-vm> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181102160122.GH194472@sasha-vm> Message-Id: <20181104091611.GC7829@rapoport-lnx> Sender: owner-linux-mm@kvack.org List-ID: To: Sasha Levin Cc: Dexuan Cui , Roman Gushchin , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , Kernel Team , Shakeel Butt , Michal Hocko , Johannes Weiner , Tejun Heo , Rik van Riel , Konstantin Khlebnikov , Matthew Wilcox , "Stable@vger.kernel.org" On Fri, Nov 02, 2018 at 12:01:22PM -0400, Sasha Levin wrote: > On Fri, Nov 02, 2018 at 02:45:42AM +0000, Dexuan Cui wrote: > >>From: Roman Gushchin > >>Sent: Thursday, November 1, 2018 17:58 > >> > >>On Fri, Nov 02, 2018 at 12:16:02AM +0000, Dexuan Cui wrote: > >>Hello, Dexuan! > >> > >>A couple of issues has been revealed recently, here are fixes > >>(hashes are from the next tree): > >> > >>5f4b04528b5f mm: don't reclaim inodes with many attached pages > >>5a03b371ad6a mm: handle no memcg case in memcg_kmem_charge() > >>properly > >> > >>These two patches should be added to the serie. > > > >Thanks for the new info! > > > >>Re stable backporting, I'd really wait for some time. Memory reclaim is a > >>quite complex and fragile area, so even if patches are correct by themselves, > >>they can easily cause a regression by revealing some other issues (as it was > >>with the inode reclaim case). > > > >I totally agree. I'm now just wondering if there is any temporary workaround, > >even if that means we have to run the kernel with some features disabled or > >with a suboptimal performance? > > I'm not sure what workload you're seeing it on, but if you could merge > these 7 patches and see that it solves the problem you're seeing and > doesn't cause any regressions it'll be a useful test for the rest of us. AFAIK, with Roman's patches backported to Ubuntu version of 4.15, the problem reported at [1] is solved. [1] https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1792349 > -- > Thanks, > Sasha > -- Sincerely yours, Mike.