From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ot1-f69.google.com (mail-ot1-f69.google.com [209.85.210.69]) by kanga.kvack.org (Postfix) with ESMTP id 2FBE16B026F for ; Wed, 31 Oct 2018 17:42:13 -0400 (EDT) Received: by mail-ot1-f69.google.com with SMTP id d34so12490664otb.10 for ; Wed, 31 Oct 2018 14:42:13 -0700 (PDT) Received: from mx1.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id k36-v6si12947864pgb.20.2018.10.31.14.42.11 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 31 Oct 2018 14:42:11 -0700 (PDT) Date: Wed, 31 Oct 2018 22:42:08 +0100 From: Michal Hocko Subject: Re: [PATCH] memory_hotplug: cond_resched in __remove_pages Message-ID: <20181031214208.GA5564@dhcp22.suse.cz> References: <20181031125840.23982-1-mhocko@kernel.org> <20181031121550.2f0cbd10a948880e534beaf7@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181031121550.2f0cbd10a948880e534beaf7@linux-foundation.org> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: Dan Williams , Johannes Thumshirn , linux-mm@kvack.org, LKML On Wed 31-10-18 12:15:50, Andrew Morton wrote: > On Wed, 31 Oct 2018 13:58:40 +0100 Michal Hocko wrote: > > > From: Michal Hocko > > > > We have received a bug report that unbinding a large pmem (>1TB) > > can result in a soft lockup: > > > > ... > > > > It has been reported on an older (4.12) kernel but the current upstream > > code doesn't cond_resched in the hot remove code at all and the given > > range to remove might be really large. Fix the issue by calling cond_resched > > once per memory section. > > > > Worthy of a cc:stable, I suggest? It is simple enough and we will surely have it in 4.12 based SLES kernels. So I do not really mind cc: stable. -- Michal Hocko SUSE Labs