From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michal Hocko Date: Mon, 01 Jul 2019 10:27:56 +0000 Subject: Re: [PATCH v3 10/11] mm/memory_hotplug: Make unregister_memory_block_under_nodes() never fail Message-Id: <20190701102756.GO6376@dhcp22.suse.cz> List-Id: References: <20190527111152.16324-1-david@redhat.com> <20190527111152.16324-11-david@redhat.com> <20190701085144.GJ6376@dhcp22.suse.cz> <20190701093640.GA17349@linux> In-Reply-To: <20190701093640.GA17349@linux> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Oscar Salvador Cc: linux-s390@vger.kernel.org, Alex Deucher , linux-ia64@vger.kernel.org, David Hildenbrand , Greg Kroah-Hartman , Mark Brown , linux-sh@vger.kernel.org, linux-kernel@vger.kernel.org, Wei Yang , linux-mm@kvack.org, "David S. Miller" , Jonathan Cameron , "Rafael J. Wysocki" , Igor Mammedov , akpm@linux-foundation.org, Chris Wilson , linuxppc-dev@lists.ozlabs.org, Dan Williams , linux-arm-kernel@lists.infradead.org On Mon 01-07-19 11:36:44, Oscar Salvador wrote: > On Mon, Jul 01, 2019 at 10:51:44AM +0200, Michal Hocko wrote: > > Yeah, we do not allow to offline multi zone (node) ranges so the current > > code seems to be over engineered. > > > > Anyway, I am wondering why do we have to strictly check for already > > removed nodes links. Is the sysfs code going to complain we we try to > > remove again? > > No, sysfs will silently "fail" if the symlink has already been removed. > At least that is what I saw last time I played with it. > > I guess the question is what if sysfs handling changes in the future > and starts dropping warnings when trying to remove a symlink is not there. > Maybe that is unlikely to happen? And maybe we handle it then rather than have a static allocation that everybody with hotremove configured has to pay for. -- Michal Hocko SUSE Labs