Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755038AbbLDBTK (ORCPT ); Thu, 3 Dec 2015 20:19:10 -0500 Received: from mga01.intel.com ([192.55.52.88]:21896 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754799AbbLDBOy (ORCPT ); Thu, 3 Dec 2015 20:14:54 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.20,378,1444719600"; d="scan'208";a="864315965" Subject: [PATCH 21/34] x86, pkeys: dump PKRU with other kernel registers To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, x86@kernel.org, Dave Hansen , dave.hansen@linux.intel.com From: Dave Hansen Date: Thu, 03 Dec 2015 17:14:53 -0800 References: <20151204011424.8A36E365@viggo.jf.intel.com> In-Reply-To: <20151204011424.8A36E365@viggo.jf.intel.com> Message-Id: <20151204011453.007731D7@viggo.jf.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1387 Lines: 35 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 2015-12-03 16:21:27.874773264 -0800 +++ b/arch/x86/kernel/process_64.c 2015-12-03 16:21:27.877773400 -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) _ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/