From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753472AbbKQDj3 (ORCPT ); Mon, 16 Nov 2015 22:39:29 -0500 Received: from mga09.intel.com ([134.134.136.24]:36118 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753228AbbKQDf4 (ORCPT ); Mon, 16 Nov 2015 22:35:56 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.20,305,1444719600"; d="scan'208";a="852570383" Subject: [PATCH 24/37] x86, pkeys: dump PKRU with other kernel registers To: linux-kernel@vger.kernel.org Cc: x86@kernel.org, Dave Hansen , dave.hansen@linux.intel.com From: Dave Hansen Date: Mon, 16 Nov 2015 19:35:44 -0800 References: <20151117033511.BFFA1440@viggo.jf.intel.com> In-Reply-To: <20151117033511.BFFA1440@viggo.jf.intel.com> Message-Id: <20151117033544.A730AE35@viggo.jf.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dave Hansen I'm a bit ambivalent about whether this is needed or not. Protection Keys never affect kernel mappings. But, they can affect whether the kernel will fault when it touches a user mapping. But, the kernel doesn't touch user mappings without some careful choreography and these accesses don't generally result in oopses. Signed-off-by: Dave Hansen --- b/arch/x86/kernel/process_64.c | 2 ++ 1 file changed, 2 insertions(+) diff -puN arch/x86/kernel/process_64.c~pkeys-30-kernel-error-dumps arch/x86/kernel/process_64.c --- a/arch/x86/kernel/process_64.c~pkeys-30-kernel-error-dumps 2015-11-16 12:35:46.445675988 -0800 +++ b/arch/x86/kernel/process_64.c 2015-11-16 12:35:46.449676170 -0800 @@ -116,6 +116,8 @@ void __show_regs(struct pt_regs *regs, i printk(KERN_DEFAULT "DR0: %016lx DR1: %016lx DR2: %016lx\n", d0, d1, d2); printk(KERN_DEFAULT "DR3: %016lx DR6: %016lx DR7: %016lx\n", d3, d6, d7); + if (boot_cpu_has(X86_FEATURE_OSPKE)) + printk(KERN_DEFAULT "PKRU: %08x\n", read_pkru()); } void release_thread(struct task_struct *dead_task) _