Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965776Ab3HHRQe (ORCPT ); Thu, 8 Aug 2013 13:16:34 -0400 Received: from g4t0017.houston.hp.com ([15.201.24.20]:26956 "EHLO g4t0017.houston.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965639Ab3HHRQc (ORCPT ); Thu, 8 Aug 2013 13:16:32 -0400 Message-ID: <1375982120.10300.212.camel@misato.fc.hp.com> Subject: Re: Cannot hot remove a memory device From: Toshi Kani To: "Rafael J. Wysocki" Cc: Yasuaki Ishimatsu , rafael.j.wysocki@intel.com, vasilis.liaskovitis@profitbricks.com, linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, tangchen@cn.fujitsu.com, wency@cn.fujitsu.com Date: Thu, 08 Aug 2013 11:15:20 -0600 In-Reply-To: <1375488280.10300.124.camel@misato.fc.hp.com> References: <51FA1E41.20304@jp.fujitsu.com> <2995879.KDC1gYpzij@vostro.rjw.lan> <1375479975.10300.105.camel@misato.fc.hp.com> <2124016.41i4c3lbD4@vostro.rjw.lan> <1375488280.10300.124.camel@misato.fc.hp.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.6.4 (3.6.4-3.fc18) Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1588 Lines: 36 On Fri, 2013-08-02 at 18:04 -0600, Toshi Kani wrote: > On Sat, 2013-08-03 at 01:43 +0200, Rafael J. Wysocki wrote: > > On Friday, August 02, 2013 03:46:15 PM Toshi Kani wrote: > > > On Thu, 2013-08-01 at 23:43 +0200, Rafael J. Wysocki wrote: : > > > I think it fails with -EINVAL at the place with dev_warn(dev, "ACPI > > > handle is already set\n"). When two ACPI memory objects associate with > > > a same memory block, the bind procedure of the 2nd ACPI memory object > > > sees that ACPI_HANDLE(dev) is already set to the 1st ACPI memory object. > > > > That sound's plausible, but I wonder how we can fix that? > > > > There's no way for a single physical device to have two different ACPI > > "companions". It looks like the memory blocks should be 64 M each in that > > case. Or we need to create two child devices for each memory block and > > associate each of them with an ACPI object. That would lead to complications > > in the user space interface, though. > > Right. Even bigger issue is that I do not think __add_pages() and > __remove_pages() can add / delete a memory chunk that is less than > 128MB. 128MB is the granularity of them. So, we may just have to fail > this case gracefully. FYI: I have submitted the patch blow to close this part of the issue... https://lkml.org/lkml/2013/8/8/396 Thanks, -Toshi -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/