From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751659AbdJTDls (ORCPT ); Thu, 19 Oct 2017 23:41:48 -0400 Received: from mail.cn.fujitsu.com ([183.91.158.132]:10890 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750968AbdJTDlr (ORCPT ); Thu, 19 Oct 2017 23:41:47 -0400 X-IronPort-AV: E=Sophos;i="5.43,368,1503331200"; d="scan'208";a="29401783" Date: Fri, 20 Oct 2017 11:41:19 +0800 From: Chao Fan To: Dou Liyang CC: , , , , , , , , Subject: Re: [PATCH 2/4] kaslr: select the memory region in immovable node to process Message-ID: <20171020034117.GB5635@localhost.localdomain> References: <20171019100243.25259-1-fanc.fnst@cn.fujitsu.com> <20171019100243.25259-3-fanc.fnst@cn.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.1 (2017-09-22) X-Originating-IP: [10.167.225.56] X-yoursite-MailScanner-ID: DC68548029C3.AACD7 X-yoursite-MailScanner: Found to be clean X-yoursite-MailScanner-From: fanc.fnst@cn.fujitsu.com Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Oct 20, 2017 at 11:17:26AM +0800, Dou Liyang wrote: >Hi Chao > Hi Dou-san, >At 10/19/2017 06:02 PM, Chao Fan wrote: >> Since the interrelationship between e820 or efi entries and memory >> region in immovable_mem is different: >> One memory region in one node may contain several entries of e820 or >> efi sometimes, and one entry of e820 or efi may contain the memory in >> different nodes sometimes. So select the intersection as a region to >> process_mem_region. It may split one node or one entry to several regions. >> >> Signed-off-by: Chao Fan >> --- >> arch/x86/boot/compressed/kaslr.c | 72 ++++++++++++++++++++++++++++++++-------- >> 1 file changed, 58 insertions(+), 14 deletions(-) >> >> diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c >> index 3c1f5204693b..22330cbe8515 100644 >> --- a/arch/x86/boot/compressed/kaslr.c >> +++ b/arch/x86/boot/compressed/kaslr.c >> @@ -563,6 +563,7 @@ static void process_mem_region(struct mem_vector *entry, >> end = min(entry->size + entry->start, mem_limit); >> if (entry->start >= end) >> return; >> + >> cur_entry.start = entry->start; >> cur_entry.size = end - entry->start; > >Above code has nothing to do with this patch. remove it. > >> >> @@ -621,6 +622,52 @@ static void process_mem_region(struct mem_vector *entry, >> } >> } >> >> +static bool select_immovable_node(unsigned long long start, >> + unsigned long long size, >> + unsigned long long minimum, >> + unsigned long long image_size) >> +{ >> + struct mem_vector region; >> + int i; >> + >> + if (num_immovable_region == 0) { > >Seems it more better: > >#ifdef CONFIG_MEMORY_HOTPLUG >for (i = 0; i < num_immovable_region; i++) { > ... >} >#else >... >process_mem_region(®ion, minimum, image_size); >... >#endif No, if we set CONFIG_MEMORY_HOTPLUG=y(the default is y in fedora), but we do not use movable_node, we should go to process_mem_region straight, right? But in your change, we still go to the for(...), even if num_immovable_region == 0. So if num_immovable_region is 0, it includes the situation of CONFIG_MEMORY_HOTPLUG=n > >> + region.start = start; >> + region.size = size; >> + process_mem_region(®ion, minimum, image_size); >> + >> + if (slot_area_index == MAX_SLOT_AREA) { >> + debug_putstr("Aborted memmap scan (slot_areas full)!\n"); >> + return 1; >> + } >> + } else { >> + for (i = 0; i < num_immovable_region; i++) { >> + unsigned long long end, select_end; >> + unsigned long long region_start, region_end; >> + >> + end = start + size - 1; >> + region_start = immovable_mem[i].start; >> + region_end = region_start + immovable_mem[i].size - 1; >> + >> + if (end < region_start || start > region_end) >> + continue; >> + >> + region.start = start > region_start ? >> + start : region_start; >> + select_end = end > region_end ? region_end : end; >> + >> + region.size = select_end - region.start + 1; >> + >> + process_mem_region(®ion, minimum, image_size); >> + >> + if (slot_area_index == MAX_SLOT_AREA) { >> + debug_putstr("Aborted memmap scan (slot_areas full)!\n"); >> + return 1; >> + } >> + } >> + } >> + return 0; >> +} >> + >> #ifdef CONFIG_EFI >> /* >> * Returns true if mirror region found (and must have been processed >> @@ -631,7 +678,6 @@ process_efi_entries(unsigned long minimum, unsigned long image_size) >> { >> struct efi_info *e = &boot_params->efi_info; >> bool efi_mirror_found = false; >> - struct mem_vector region; >> efi_memory_desc_t *md; >> unsigned long pmap; >> char *signature; >> @@ -664,6 +710,8 @@ process_efi_entries(unsigned long minimum, unsigned long image_size) >> } >> >> for (i = 0; i < nr_desc; i++) { >> + unsigned long long start, size; >> + >> md = efi_early_memdesc_ptr(pmap, e->efi_memdesc_size, i); >> >> /* >> @@ -684,13 +732,11 @@ process_efi_entries(unsigned long minimum, unsigned long image_size) >> !(md->attribute & EFI_MEMORY_MORE_RELIABLE)) >> continue; >> >> - region.start = md->phys_addr; >> - region.size = md->num_pages << EFI_PAGE_SHIFT; >> - process_mem_region(®ion, minimum, image_size); >> - if (slot_area_index == MAX_SLOT_AREA) { >> - debug_putstr("Aborted EFI scan (slot_areas full)!\n"); >> + start = md->phys_addr; >> + size = md->num_pages << EFI_PAGE_SHIFT; >> + >> + if (select_immovable_node(start, size, minimum, image_size)) > >Why you replace the region with two parameters? Just use region. > You can see the commit message, we may splite one entry to more regions, so there will be region.start compared with memory region in immovable_mem and then fill more new regions if we use region here. The code will look strange. Start and size will be more clear. Thanks, Chao Fan >> break; >> - } >> } >> return true; >> } >> @@ -706,22 +752,20 @@ static void process_e820_entries(unsigned long minimum, >> unsigned long image_size) >> { >> int i; >> - struct mem_vector region; >> struct boot_e820_entry *entry; >> >> /* Verify potential e820 positions, appending to slots list. */ >> for (i = 0; i < boot_params->e820_entries; i++) { >> + unsigned long long start, size; >> entry = &boot_params->e820_table[i]; >> /* Skip non-RAM entries. */ >> if (entry->type != E820_TYPE_RAM) >> continue; >> - region.start = entry->addr; >> - region.size = entry->size; >> - process_mem_region(®ion, minimum, image_size); >> - if (slot_area_index == MAX_SLOT_AREA) { >> - debug_putstr("Aborted e820 scan (slot_areas full)!\n"); >> + start = entry->addr; >> + size = entry->size; >> + >> + if (select_immovable_node(start, size, minimum, image_size)) >ditto > >Thanks, > dou. >> break; >> - } >> } >> } >> >>