From mboxrd@z Thu Jan 1 00:00:00 1970 From: Toshi Kani Subject: Re: [Bug fix PATCH] ACPI,acpi_memhotplug: enable acpi_memory_info->enabled of memory device presented at boot-time Date: Wed, 13 Mar 2013 08:50:13 -0600 Message-ID: <1363186213.12845.174.camel@misato.fc.hp.com> References: <514022BF.3080303@jp.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: Received: from g4t0017.houston.hp.com ([15.201.24.20]:6865 "EHLO g4t0017.houston.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932759Ab3CMPBV (ORCPT ); Wed, 13 Mar 2013 11:01:21 -0400 In-Reply-To: <514022BF.3080303@jp.fujitsu.com> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Yasuaki Ishimatsu Cc: rjw@sisk.pl, linux-acpi@vger.kernel.org, tangchen@cn.fujitsu.com, wency@cn.fujitsu.com, laijs@cn.fujitsu.com, linux-kernel@vger.kernel.org On Wed, 2013-03-13 at 15:54 +0900, Yasuaki Ishimatsu wrote: > At http://marc.info/?l=linux-acpi&m=135769405622667&w=2 thread, > Toshi Kani mentioned as follows: > > "I have a question about the change you made in commit 65479472 in > acpi_memhotplug.c. This change seems to require that > acpi_memory_enable_device() calls add_memory() to add all memory ranges > represented by memory device objects at boot-time, and keep the results > be used for hot-remove. > > If I understand it right, this add_memory() call fails with EEXIST at > boot-time since all memory ranges should have been added from EFI memory > table (or e820) already. This results all memory ranges be marked as ! > enabled & !failed. I think this means that we cannot hot-delete any > memory ranges presented at boot-time since acpi_memory_remove_memory() > only calls remove_memory() when the enabled flag is set. Is that > correct?" > > Above mention is correct. Thus even if memory device supports hotplug, > memory presented at boot-time cannot be hot removed since the memory > device's acpi_memory_info->enabled is always 0. > > This patch changes to set 1 to "acpi_memory_info->enabled" of memory > device presented at boot-time for hot removing the memory device. > > Signed-off-by: Yasuaki Ishimatsu > > --- > drivers/acpi/acpi_memhotplug.c | 4 ++-- > 1 files changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/acpi/acpi_memhotplug.c b/drivers/acpi/acpi_memhotplug.c > index da1f82b..88fd46a 100644 > --- a/drivers/acpi/acpi_memhotplug.c > +++ b/drivers/acpi/acpi_memhotplug.c > @@ -254,8 +254,8 @@ static int acpi_memory_enable_device(struct acpi_memory_device *mem_device) > continue; > } > > - if (!result) > - info->enabled = 1; > + info->enabled = 1; Do we still need to keep the enable bit? I think !failed means enabled with this change. Thanks, -Toshi