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=-8.4 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_MUTT 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 6DE28C67839 for ; Thu, 13 Dec 2018 18:12:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4879E20870 for ; Thu, 13 Dec 2018 18:12:56 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4879E20870 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.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 S1729899AbeLMSMz (ORCPT ); Thu, 13 Dec 2018 13:12:55 -0500 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:39962 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727929AbeLMSMy (ORCPT ); Thu, 13 Dec 2018 13:12:54 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 63347A78; Thu, 13 Dec 2018 10:12:54 -0800 (PST) Received: from edgewater-inn.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.72.51.249]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 32EA13F575; Thu, 13 Dec 2018 10:12:54 -0800 (PST) Received: by edgewater-inn.cambridge.arm.com (Postfix, from userid 1000) id 16B9A1AE0838; Thu, 13 Dec 2018 18:13:18 +0000 (GMT) Date: Thu, 13 Dec 2018 18:13:18 +0000 From: Will Deacon To: Miles Chen Cc: Catalin Marinas , Matthias Brugger , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mediatek@lists.infradead.org, wsd_upstream@mediatek.com, ard.biesheuvel@linaro.org Subject: Re: [PATCH] arm64: kaslr: print PHYS_OFFSET in dump_kernel_offset() Message-ID: <20181213181317.GD18185@edgewater-inn.cambridge.arm.com> References: <1544612209-13660-1-git-send-email-miles.chen@mediatek.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1544612209-13660-1-git-send-email-miles.chen@mediatek.com> User-Agent: Mutt/1.11.1+30 (d10eec459b35) () Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [+Ard because I'll basically go with his preference on this one] On Wed, Dec 12, 2018 at 06:56:49PM +0800, Miles Chen wrote: > When debug with kaslr, it is sometimes necessary to have PHYS_OFFSET to > perform linear virtual address to physical address translation. > Sometimes we're debugging with only few information such as a kernel log > and a symbol file, print PHYS_OFFSET in dump_kernel_offset() for that case. > > Tested by: > echo c > /proc/sysrq-trigger > [ 11.996161] SMP: stopping secondary CPUs > [ 11.996732] Kernel Offset: 0x2522200000 from 0xffffff8008000000 > [ 11.996881] PHYS_OFFSET: 0xffffffeb40000000 > > Signed-off-by: Miles Chen > Tested-by: Miles Chen > --- > arch/arm64/kernel/setup.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c > index f4fc1e0544b7..4b0e1231625c 100644 > --- a/arch/arm64/kernel/setup.c > +++ b/arch/arm64/kernel/setup.c > @@ -388,6 +388,7 @@ static int dump_kernel_offset(struct notifier_block *self, unsigned long v, > if (IS_ENABLED(CONFIG_RANDOMIZE_BASE) && offset > 0) { > pr_emerg("Kernel Offset: 0x%lx from 0x%lx\n", > offset, KIMAGE_VADDR); > + pr_emerg("PHYS_OFFSET: 0x%llx\n", PHYS_OFFSET); > } else { > pr_emerg("Kernel Offset: disabled\n"); > } > -- > 2.18.0 >