From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f173.google.com (mail-pf0-f173.google.com [209.85.192.173]) by kanga.kvack.org (Postfix) with ESMTP id B857A6B0005 for ; Wed, 6 Apr 2016 14:53:36 -0400 (EDT) Received: by mail-pf0-f173.google.com with SMTP id c20so39061666pfc.1 for ; Wed, 06 Apr 2016 11:53:36 -0700 (PDT) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org. [140.211.169.12]) by mx.google.com with ESMTPS id rw6si1222687pab.80.2016.04.06.11.53.35 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 06 Apr 2016 11:53:35 -0700 (PDT) Date: Wed, 6 Apr 2016 11:53:34 -0700 From: Andrew Morton Subject: Re: [PATCH 0/2] memory_hotplug: introduce config and command line options to set the default onlining policy Message-Id: <20160406115334.82af80e922f8b3eec6336a8b@linux-foundation.org> In-Reply-To: <1459950312-25504-1-git-send-email-vkuznets@redhat.com> References: <1459950312-25504-1-git-send-email-vkuznets@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Vitaly Kuznetsov Cc: linux-mm@kvack.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, Jonathan Corbet , Dan Williams , "Kirill A. Shutemov" , Mel Gorman , David Vrabel , David Rientjes , Igor Mammedov , Lennart Poettering On Wed, 6 Apr 2016 15:45:10 +0200 Vitaly Kuznetsov wrote: > This patchset continues the work I started with: > > commit 31bc3858ea3ebcc3157b3f5f0e624c5962f5a7a6 > Author: Vitaly Kuznetsov > Date: Tue Mar 15 14:56:48 2016 -0700 > > memory-hotplug: add automatic onlining policy for the newly added memory > > Initially I was going to stop there and bring the policy setting logic to > userspace. I met two issues on this way: > > 1) It is possible to have memory hotplugged at boot (e.g. with QEMU). These > blocks stay offlined if we turn the onlining policy on by userspace. > > 2) My attempt to bring this policy setting to systemd failed, systemd > maintainers suggest to change the default in kernel or ... to use tmpfiles.d > to alter the policy (which looks like a hack to me): > https://github.com/systemd/systemd/pull/2938 That discussion really didn't come to a conclusion and I don't understand why you consider Lennert's "recommended way" to be a hack? > Here I suggest to add a config option to set the default value for the policy > and a kernel command line parameter to make the override. But the patchset looks pretty reasonable regardless of the above. -- 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