From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 21200C43143 for ; Tue, 2 Oct 2018 10:18:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CDF0920878 for ; Tue, 2 Oct 2018 10:18:50 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CDF0920878 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=zytor.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727503AbeJBRBV (ORCPT ); Tue, 2 Oct 2018 13:01:21 -0400 Received: from terminus.zytor.com ([198.137.202.136]:57079 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726178AbeJBRBV (ORCPT ); Tue, 2 Oct 2018 13:01:21 -0400 Received: from terminus.zytor.com (localhost [127.0.0.1]) by terminus.zytor.com (8.15.2/8.15.2) with ESMTPS id w92AI8UU1917678 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Tue, 2 Oct 2018 03:18:08 -0700 Received: (from tipbot@localhost) by terminus.zytor.com (8.15.2/8.15.2/Submit) id w92AI8051917675; Tue, 2 Oct 2018 03:18:08 -0700 Date: Tue, 2 Oct 2018 03:18:08 -0700 X-Authentication-Warning: terminus.zytor.com: tipbot set sender to tipbot@zytor.com using -f From: tip-bot for Masayoshi Mizuma Message-ID: Cc: mingo@kernel.org, tglx@linutronix.de, peterz@infradead.org, m.mizuma@jp.fujitsu.com, bhe@redhat.com, linux-kernel@vger.kernel.org, torvalds@linux-foundation.org, msys.mizuma@gmail.com, hpa@zytor.com, bp@alien8.de Reply-To: torvalds@linux-foundation.org, msys.mizuma@gmail.com, hpa@zytor.com, bp@alien8.de, tglx@linutronix.de, mingo@kernel.org, m.mizuma@jp.fujitsu.com, peterz@infradead.org, linux-kernel@vger.kernel.org, bhe@redhat.com In-Reply-To: <20181001140843.26137-2-msys.mizuma@gmail.com> References: <20181001140843.26137-2-msys.mizuma@gmail.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/boot] x86/mm: Add a kernel parameter to change the padding used for the physical memory mapping Git-Commit-ID: e79ac9354cf95d75ff6afd341f9c5aa5cbcd638b X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: e79ac9354cf95d75ff6afd341f9c5aa5cbcd638b Gitweb: https://git.kernel.org/tip/e79ac9354cf95d75ff6afd341f9c5aa5cbcd638b Author: Masayoshi Mizuma AuthorDate: Mon, 1 Oct 2018 10:08:41 -0400 Committer: Ingo Molnar CommitDate: Tue, 2 Oct 2018 11:47:20 +0200 x86/mm: Add a kernel parameter to change the padding used for the physical memory mapping If each node of physical memory layout has huge space for hotplug, the padding used for the physical memory mapping section is not enough. For exapmle of the layout: SRAT: Node 6 PXM 4 [mem 0x100000000000-0x13ffffffffff] hotplug SRAT: Node 7 PXM 5 [mem 0x140000000000-0x17ffffffffff] hotplug SRAT: Node 2 PXM 6 [mem 0x180000000000-0x1bffffffffff] hotplug SRAT: Node 3 PXM 7 [mem 0x1c0000000000-0x1fffffffffff] hotplug We can increase the padding via CONFIG_RANDOMIZE_MEMORY_PHYSICAL_PADDING, however, the needed padding size depends on the system environment. The kernel option is better than changing the config. Signed-off-by: Masayoshi Mizuma Reviewed-by: Baoquan He Cc: Borislav Petkov Cc: Linus Torvalds Cc: Masayoshi Mizuma Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/20181001140843.26137-2-msys.mizuma@gmail.com Signed-off-by: Ingo Molnar --- arch/x86/mm/kaslr.c | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c index 61db77b0eda9..00cf4cae38f5 100644 --- a/arch/x86/mm/kaslr.c +++ b/arch/x86/mm/kaslr.c @@ -40,6 +40,7 @@ */ static const unsigned long vaddr_end = CPU_ENTRY_AREA_BASE; +int __initdata rand_mem_physical_padding = CONFIG_RANDOMIZE_MEMORY_PHYSICAL_PADDING; /* * Memory regions randomized by KASLR (except modules that use a separate logic * earlier during boot). The list is ordered based on virtual addresses. This @@ -69,6 +70,20 @@ static inline bool kaslr_memory_enabled(void) return kaslr_enabled() && !IS_ENABLED(CONFIG_KASAN); } +static int __init rand_mem_physical_padding_setup(char *str) +{ + int max_padding = (1 << (MAX_PHYSMEM_BITS - TB_SHIFT)) - 1; + + get_option(&str, &rand_mem_physical_padding); + if (rand_mem_physical_padding < 0) + rand_mem_physical_padding = 0; + else if (rand_mem_physical_padding > max_padding) + rand_mem_physical_padding = max_padding; + + return 0; +} +early_param("rand_mem_physical_padding", rand_mem_physical_padding_setup); + /* Initialize base and padding for each memory region randomized with KASLR */ void __init kernel_randomize_memory(void) { @@ -102,7 +117,7 @@ void __init kernel_randomize_memory(void) */ BUG_ON(kaslr_regions[0].base != &page_offset_base); memory_tb = DIV_ROUND_UP(max_pfn << PAGE_SHIFT, 1UL << TB_SHIFT) + - CONFIG_RANDOMIZE_MEMORY_PHYSICAL_PADDING; + rand_mem_physical_padding; /* Adapt phyiscal memory region size based on available memory */ if (memory_tb < kaslr_regions[0].size_tb)