From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759535AbcAKK7j (ORCPT ); Mon, 11 Jan 2016 05:59:39 -0500 Received: from mail-wm0-f68.google.com ([74.125.82.68]:35450 "EHLO mail-wm0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759107AbcAKK7h (ORCPT ); Mon, 11 Jan 2016 05:59:37 -0500 Date: Mon, 11 Jan 2016 11:59:33 +0100 From: Ingo Molnar To: Shuah Khan Cc: Andy Lutomirski , x86@kernel.org, Borislav Petkov , linux-kernel@vger.kernel.org Subject: Re: [PATCH] selftests/x86: Disable ldt_gdt_64 for now Message-ID: <20160111105933.GA663@gmail.com> References: <8dd42ba6434d84eefe6d864fb453fbe34d43098c.1452109816.git.luto@kernel.org> <568ECF61.4040007@osg.samsung.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <568ECF61.4040007@osg.samsung.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Shuah Khan wrote: > On 01/06/2016 12:51 PM, Andy Lutomirski wrote: > > ldt_gdt.c relies on cross-cpu invalidation of SS to do one of its > > tests. On 32-bit builds, this works fine, but on 64-bit builds, it > > only works if the kernel has proper SS sigcontext handling for > > 64-bit user programs. > > > > Since the SS fixes are currently reverted, restrict the test case to > > 32 bits for now. > > > > In principle, I could change the test to use a different segment > > register, but it would be messy: CS can't point to the LDT for > > 64-bit code, and the other registers don't result in immediate > > faults because they aren't reloaded on kernel -> user transitions. > > > > When we fix sigcontext (in 4.6?), we can revert this. > > > > Signed-off-by: Andy Lutomirski > > -- > > Andy, > > This patch didn't apply to linux-kselftest next. > It probably has to go through x86. It doesn't apply to -tip either. Andy, which tree is this against? Thanks, Ingo