From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752840AbdJGBkB (ORCPT ); Fri, 6 Oct 2017 21:40:01 -0400 Received: from mail.kernel.org ([198.145.29.99]:56436 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751485AbdJGBkA (ORCPT ); Fri, 6 Oct 2017 21:40:00 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org ADCC021883 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=rostedt@goodmis.org Date: Fri, 6 Oct 2017 21:39:56 -0400 From: Steven Rostedt To: LKML Cc: Andy Lutomirski , Nadav Amit , Boris Ostrovsky , Thomas Gleixner , Ingo Molnar , Linus Torvalds Subject: [BUG] GPF on reboot of box Message-ID: <20171006213956.0b33cf61@gandalf.local.home> X-Mailer: Claws Mail 3.14.0 (GTK+ 2.24.31; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Starting with v4.14-rc1 my box crashes during a reboot. All I get is the following: [ 250.615793] sd 0:0:0:0: [sda] Synchronizing SCSI cache [ 250.635639] reboot: Restarting system [ 250.639671] reboot: machine restart [ 250.643842] general protection fault: 0000 [#1] PREEMPT SMP KASAN Then nothing. No reboot, it just hangs there. I bisected it down to this commit: 660da7c9228f ("x86/mm: Enable CR4.PCIDE on supported systems") If I comment out the setting of X86_CR4_PCIDE in that commit, it boots fine. But... I noticed that commit c7ad5ad29 ("x86/mm/64: Initialize CR4.PCIDE early") moved the problem code from arch/x86/kernel/cpu/common.c to arch/x86/mm/init.c If I comment it out in v4.14-rc1, it crashes on boot up. It appears that my box doesn't like having X86_CR4_PCIDE set. it causes reboot to fail. But it also appears that setting that is required for some other code to work. Help! -- Steve