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=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable 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 EE5CAC433E0 for ; Thu, 4 Feb 2021 15:49:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BC63B64F51 for ; Thu, 4 Feb 2021 15:49:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237503AbhBDPr4 (ORCPT ); Thu, 4 Feb 2021 10:47:56 -0500 Received: from elvis.franken.de ([193.175.24.41]:52342 "EHLO elvis.franken.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237499AbhBDPjV (ORCPT ); Thu, 4 Feb 2021 10:39:21 -0500 Received: from uucp (helo=alpha) by elvis.franken.de with local-bsmtp (Exim 3.36 #1) id 1l7giJ-00066e-00; Thu, 04 Feb 2021 16:38:35 +0100 Received: by alpha.franken.de (Postfix, from userid 1000) id F2437C0D5A; Thu, 4 Feb 2021 16:36:23 +0100 (CET) Date: Thu, 4 Feb 2021 16:36:23 +0100 From: Thomas Bogendoerfer To: Jinyang He Cc: Huacai Chen , Jiaxun Yang , linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 2/2] MIPS: relocatable: Use __kaslr_offset in show_kernel_relocation Message-ID: <20210204153623.GA14818@alpha.franken.de> References: <1612348510-29569-1-git-send-email-hejinyang@loongson.cn> <1612348510-29569-2-git-send-email-hejinyang@loongson.cn> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1612348510-29569-2-git-send-email-hejinyang@loongson.cn> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Feb 03, 2021 at 06:35:10PM +0800, Jinyang He wrote: > The type of the VMLINUX_LOAD_ADDRESS macro is the (unsigned long long) > in 32bits kernel but (unsigned long) in the 64-bit kernel. Although there > is no error here, avoid using it to calculate kaslr_offset. And here we > may need is that the address of __kaslr_offset rather than (void *)offset. > > Signed-off-by: Jinyang He > --- > arch/mips/kernel/relocate.c | 8 ++------ > 1 file changed, 2 insertions(+), 6 deletions(-) > > diff --git a/arch/mips/kernel/relocate.c b/arch/mips/kernel/relocate.c > index 95abb9c..52018a3 100644 > --- a/arch/mips/kernel/relocate.c > +++ b/arch/mips/kernel/relocate.c > @@ -430,13 +430,9 @@ void *__init relocate_kernel(void) > */ > static void show_kernel_relocation(const char *level) > { > - unsigned long offset; > - > - offset = __pa_symbol(_text) - __pa_symbol(VMLINUX_LOAD_ADDRESS); > - > - if (IS_ENABLED(CONFIG_RELOCATABLE) && offset > 0) { > + if (__kaslr_offset > 0) { > printk(level); > - pr_cont("Kernel relocated by 0x%pK\n", (void *)offset); > + pr_cont("Kernel relocated by 0x%pK\n", &__kaslr_offset); are you sure ? I would have expected (void *)__kaslr_offset here. Thomas. -- Crap can work. Given enough thrust pigs will fly, but it's not necessarily a good idea. [ RFC1925, 2.3 ]