From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753203AbdFPLas (ORCPT ); Fri, 16 Jun 2017 07:30:48 -0400 Received: from mga14.intel.com ([192.55.52.115]:47572 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752801AbdFPLaq (ORCPT ); Fri, 16 Jun 2017 07:30:46 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.39,347,1493708400"; d="scan'208";a="1161263215" Date: Fri, 16 Jun 2017 14:30:24 +0300 From: "Kirill A. Shutemov" To: Ingo Molnar Cc: kernel test robot , LKP , linux-kernel@vger.kernel.org, wfg@linux.intel.com, Thomas Gleixner , "H. Peter Anvin" Subject: Re: c88d71508e ("x86/boot/64: Rewrite startup_64() in C"): BUG: kernel reboot-without-warning in early-boot stage, last printk: Booting the kernel. Message-ID: <20170616113024.ajmif63cmcszry5a@black.fi.intel.com> References: <59416012.KgnHJ9oFpPFgBi1m%fengguang.wu@intel.com> <20170616081630.mvc52ku6spchsqj4@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170616081630.mvc52ku6spchsqj4@gmail.com> User-Agent: NeoMutt/20161126 (1.7.0) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jun 16, 2017 at 10:16:30AM +0200, Ingo Molnar wrote: > > * kernel test robot wrote: > > > Greetings, > > > > 0day kernel testing robot got the below dmesg and the first bad commit is > > > > https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master > > > > commit c88d71508e36b514413464bd2e01f96f34583a0e > > Author: Kirill A. Shutemov > > AuthorDate: Tue Jun 6 14:31:26 2017 +0300 > > Commit: Ingo Molnar > > CommitDate: Tue Jun 13 08:56:54 2017 +0200 > > > > x86/boot/64: Rewrite startup_64() in C > > > > The patch write most of startup_64 logic in C. > > > > This is preparation for 5-level paging enabling. > > > > Signed-off-by: Kirill A. Shutemov > > Kirill, should I drop the 5-level paging series for now, or is there a fix in the > works? The patch below works for me, but I don't really understant all details of how linking kernel image works. Please double check that it makes sense. >>From b8c7201e97bbe86e88401376338ed92a5a53859e Mon Sep 17 00:00:00 2001 From: "Kirill A. Shutemov" Date: Fri, 16 Jun 2017 14:15:44 +0300 Subject: [PATCH] x86/boot/64: Put __startup_64() into .head.text Put __startup_64() and fixup_pointer() into .head.text section to make sure it's always near startup_64 and always callable. Signed-off-by: Kirill A. Shutemov --- arch/x86/kernel/head64.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index 2b2ac381195a..46c3c73e7f43 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -38,12 +38,14 @@ extern pmd_t early_dynamic_pgts[EARLY_DYNAMIC_PAGE_TABLES][PTRS_PER_PMD]; static unsigned int __initdata next_early_pgt; pmdval_t early_pmd_flags = __PAGE_KERNEL_LARGE & ~(_PAGE_GLOBAL | _PAGE_NX); -static void __init *fixup_pointer(void *ptr, unsigned long physaddr) +#define __head __section(.head.text) + +static void __head *fixup_pointer(void *ptr, unsigned long physaddr) { return ptr - (void *)_text + (void *)physaddr; } -void __init __startup_64(unsigned long physaddr) +void __head __startup_64(unsigned long physaddr) { unsigned long load_delta, *p; pgdval_t *pgd; -- Kirill A. Shutemov