From mboxrd@z Thu Jan 1 00:00:00 1970 From: ykzhao Subject: Re: [PATCH] x86: make sure wakeup code is below 1M -v2 Date: Thu, 12 Nov 2009 15:14:27 +0800 Message-ID: <1258010067.3802.11.camel@localhost.localdomain> References: <4AF7D820.5040503@kernel.org> <200911091315.13151.rjw@sisk.pl> <4AFA210B.3020207@kernel.org> <1257930767.31183.113.camel@localhost.localdomain> <4AFB0B02.4050306@kernel.org> <1257988632.31183.134.camel@localhost.localdomain> <4AFB7D21.6050004@kernel.org> <1257997072.3888.4.camel@localhost.localdomain> <4AFB9B60.7010009@kernel.org> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: Received: from mga11.intel.com ([192.55.52.93]:65035 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751284AbZKLHP5 (ORCPT ); Thu, 12 Nov 2009 02:15:57 -0500 In-Reply-To: <4AFB9B60.7010009@kernel.org> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Yinghai Lu Cc: "Rafael J. Wysocki" , Ingo Molnar , Thomas Gleixner , "H. Peter Anvin" , Len Brown , "linux-kernel@vger.kernel.org" , ACPI Devel Maling List , pm list On Thu, 2009-11-12 at 13:21 +0800, Yinghai Lu wrote: > ykzhao wrote: > > On Thu, 2009-11-12 at 11:12 +0800, Yinghai Lu wrote: > >> ykzhao wrote: > >>> On Thu, 2009-11-12 at 03:05 +0800, Yinghai Lu wrote: > >>>> ykzhao wrote: > >>>>> On Wed, 2009-11-11 at 10:27 +0800, Yinghai Lu wrote: > >>>>>> try to find_e820_area/reserve_early, and call acpi_reserve_memory early > >>>>>> > >>>>>> to get area is below 1M > >>>>>> > >>>>>> -v2: change function name to acpi_reserve_wakeup_memory according to Rafael > >>>>> It seems that the function of find_e820_area is called in several > >>>>> places. > >>>>> >Initmem_init: bootmap = find_e820_area(0, end_pfn< >>>>> bootmap_size, PAGE_SIZE); > >>>>> > >>>>> If we also call it in the acpi_reserve_wakeup_memory, do we get the same > >>>>> base address as that obtained in initmem_init? > >>>> no. find_e820_area will check the reserve res array that could be updated by reserve_early. > >>> It will check the reserved region array when calling the function of > >>> find_e820_area. > >>> But it seems that the array is not updated when the find_e820_area is > >>> called in the function of initmem_init. > >> right after that will use reserve_bootmem for those range in initmem_init. > > Yes. The reserve_bootmem is called for the range in initmem_init. > > But the reserved_early array is not updated. > > it is not needed anymore because bootmem for that node is ready at that point, could use > reserve_bootmem_node directly. and before that early_res_to_bootmem will convert that early resource that > fall into that node range to bootmem reserved too. After the bootmem allocator is initialized, the early_res_to_bootmem will convert the resource in reserved_early array and reserve them in the bootmem. In this patch the find_e820_area is used in the acpi_reserve_wakeup_memory, which is called after initializing the bootmem allocator. Can we still use the find_e820_area after the bootmem allocator is initialized? It seems that the bootmem bitmap is also found by using the find_e820_area. But we don't update the reserved_early array any more. Maybe we will get the overlap address with the bootmem bitmap for the wakeup code. thanks. > > please check code setup_node_bootmem/early_node_mem/early_res_to_bootmem ...and reserve_bootmem_node... > > YH