From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michal Hocko Date: Mon, 01 Jul 2019 12:46:28 +0000 Subject: Re: [PATCH v3 02/11] s390x/mm: Fail when an altmap is used for arch_add_memory() Message-Id: <20190701124628.GT6376@dhcp22.suse.cz> List-Id: References: <20190527111152.16324-1-david@redhat.com> <20190527111152.16324-3-david@redhat.com> <20190701074306.GC6376@dhcp22.suse.cz> In-Reply-To: <20190701074306.GC6376@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: David Hildenbrand Cc: Oscar Salvador , linux-s390@vger.kernel.org, linux-ia64@vger.kernel.org, Vasily Gorbik , linux-sh@vger.kernel.org, Heiko Carstens , linux-kernel@vger.kernel.org, Wei Yang , linux-mm@kvack.org, Mike Rapoport , Martin Schwidefsky , Igor Mammedov , akpm@linux-foundation.org, linuxppc-dev@lists.ozlabs.org, Dan Williams , linux-arm-kernel@lists.infradead.org On Mon 01-07-19 09:43:06, Michal Hocko wrote: > On Mon 27-05-19 13:11:43, David Hildenbrand wrote: > > ZONE_DEVICE is not yet supported, fail if an altmap is passed, so we > > don't forget arch_add_memory()/arch_remove_memory() when unlocking > > support. > > Why do we need this? Sure ZONE_DEVICE is not supported for s390 and so > might be the case for other arches which support hotplug. I do not see > much point in adding warning to each of them. I would drop this one. If there is a strong reason to have something like that it should come with a better explanation and it can be done on top. -- Michal Hocko SUSE Labs