From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx109.postini.com [74.125.245.109]) by kanga.kvack.org (Postfix) with SMTP id 2F1476B0071 for ; Thu, 15 Aug 2013 16:29:01 -0400 (EDT) Received: by mail-oa0-f50.google.com with SMTP id i4so1389561oah.23 for ; Thu, 15 Aug 2013 13:29:00 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <1376593564.10300.446.camel@misato.fc.hp.com> References: <1375956979-31877-1-git-send-email-tangchen@cn.fujitsu.com> <20130812145016.GI15892@htj.dyndns.org> <5208FBBC.2080304@zytor.com> <20130812152343.GK15892@htj.dyndns.org> <52090D7F.6060600@gmail.com> <20130812164650.GN15892@htj.dyndns.org> <5209CEC1.8070908@cn.fujitsu.com> <520A02DE.1010908@cn.fujitsu.com> <520ADBBA.10501@cn.fujitsu.com> <1376593564.10300.446.camel@misato.fc.hp.com> Date: Thu, 15 Aug 2013 13:28:59 -0700 Message-ID: Subject: Re: [PATCH part5 0/7] Arrange hotpluggable memory as ZONE_MOVABLE. From: Yinghai Lu Content-Type: text/plain; charset=ISO-8859-1 Sender: owner-linux-mm@kvack.org List-ID: To: Toshi Kani Cc: Tang Chen , Tejun Heo , Tang Chen , "H. Peter Anvin" , Bob Moore , Lv Zheng , "Rafael J. Wysocki" , Len Brown , Thomas Gleixner , Ingo Molnar , Andrew Morton , Thomas Renninger , Jiang Liu , Wen Congyang , Lai Jiangshan , Yasuaki Ishimatsu , Taku Izumi , Mel Gorman , Minchan Kim , "mina86@mina86.com" , "gong.chen@linux.intel.com" , Vasilis Liaskovitis , "lwoodman@redhat.com" , Rik van Riel , "jweiner@redhat.com" , Prarit Bhargava , Zhang Yanfei , "yanghy@cn.fujitsu.com" , the arch/x86 maintainers , "linux-doc@vger.kernel.org" , Linux Kernel Mailing List , Linux MM , ACPI Devel Maling List , "Luck, Tony (tony.luck@intel.com)" On Thu, Aug 15, 2013 at 12:06 PM, Toshi Kani wrote: > On Wed, 2013-08-14 at 09:22 +0800, Tang Chen wrote: >> On 08/14/2013 06:33 AM, Yinghai Lu wrote: >> ...... >> > >> >> relocate_initrd() >> > >> > size could be very big, like several hundreds mega bytes. >> > should be anywhere, but will be freed after booting. >> > >> > ===> so we should not limit it to near kernel range. >> > >> >> acpi_initrd_override() >> > >> > should be 64 * 10 about 1M. >> > >> >> reserve_crashkernel() >> > >> > could be under 4G, or above 4G. >> > size could be 512M or 8G whatever. >> > >> > looks like >> > should move down relocated_initrd and reserve_crashkernel. >> >> OK, will try to do this. >> >> Thank you for the explanation. :) > > So, we still need reordering, and put a new requirement that all earlier > allocations must be small... > > I think the root of this issue is that ACPI init point is not early > enough in the boot sequence. If it were much earlier already, the whole > thing would have been very simple. We are now trying to workaround this > issue in the mblock code (which itself is a fine idea), but this ACPI > issue still remains and similar issues may come up again in future. > > For instance, ACPI SCPR/DBGP/DBG2 tables allow the OS to initialize > serial console/debug ports at early boot time. The earlier it can be > initialized, the better this feature will be. These tables are not > currently used by Linux due to a licensing issue, but it could be > addressed some time soon. As platforms becoming more complex & legacy > free, the needs of ACPI tables will increase. > > I think moving up the ACPI init point earlier is a good direction. Good point. If we put acpi_initrd_override in BRK, and can more acpi_boot_table_init() much early. Yinghai -- 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