From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr0-f200.google.com (mail-wr0-f200.google.com [209.85.128.200]) by kanga.kvack.org (Postfix) with ESMTP id D05656B0038 for ; Fri, 24 Feb 2017 11:52:28 -0500 (EST) Received: by mail-wr0-f200.google.com with SMTP id v30so13739237wrc.4 for ; Fri, 24 Feb 2017 08:52:28 -0800 (PST) Received: from mx2.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id h1si10794730wrb.231.2017.02.24.08.52.27 for (version=TLS1 cipher=AES128-SHA bits=128/128); Fri, 24 Feb 2017 08:52:27 -0800 (PST) Date: Fri, 24 Feb 2017 17:52:25 +0100 From: Michal Hocko Subject: Re: [RFC PATCH] memory-hotplug: Use dev_online for memhp_auto_offline Message-ID: <20170224165224.GA9363@dhcp22.suse.cz> References: <20170223174106.GB13822@dhcp22.suse.cz> <87tw7kydto.fsf@vitty.brq.redhat.com> <20170224133714.GH19161@dhcp22.suse.cz> <87efyny90q.fsf@vitty.brq.redhat.com> <20170224144147.GJ19161@dhcp22.suse.cz> <87a89by6hd.fsf@vitty.brq.redhat.com> <20170224153227.GL19161@dhcp22.suse.cz> <8760jzy3iu.fsf@vitty.brq.redhat.com> <20170224162317.GN19161@dhcp22.suse.cz> <871suny22u.fsf@vitty.brq.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <871suny22u.fsf@vitty.brq.redhat.com> Sender: owner-linux-mm@kvack.org List-ID: To: Vitaly Kuznetsov Cc: Nathan Fontenot , linux-mm@kvack.org, mpe@ellerman.id.au, linuxppc-dev@lists.ozlabs.org, mdroth@linux.vnet.ibm.com, kys@microsoft.com On Fri 24-02-17 17:40:25, Vitaly Kuznetsov wrote: > Michal Hocko writes: > > > On Fri 24-02-17 17:09:13, Vitaly Kuznetsov wrote: [...] > >> While this will most probably work for me I still disagree with the > >> concept of 'one size fits all' here and the default 'false' for ACPI, > >> we're taking away the feature from KVM/Vmware folks so they'll again > >> come up with the udev rule which has known issues. > > > > Well, AFAIU acpi_memory_device_add is a standard way how to announce > > physical memory added to the system. Where does the KVM/VMware depend on > > this to do memory ballooning? > > As far as I understand memory hotplug in KVM/VMware is pure ACPI memory > hotplug, there is no specific code for it. VMware has its ballooning driver AFAIK and I have no idea what KVM uses. Anyway, acpi_memory_device_add is no different from doing a physical memory hotplug IIUC so there shouldn't be any difference to how it is handled. I will post the patch as an RFC sometimes next week, let's see what others think about it. -- Michal Hocko SUSE Labs -- 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