From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761992AbcALBZ2 (ORCPT ); Mon, 11 Jan 2016 20:25:28 -0500 Received: from mail-oi0-f47.google.com ([209.85.218.47]:35557 "EHLO mail-oi0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759155AbcALBZ1 (ORCPT ); Mon, 11 Jan 2016 20:25:27 -0500 MIME-Version: 1.0 In-Reply-To: <20160111105933.GA663@gmail.com> References: <8dd42ba6434d84eefe6d864fb453fbe34d43098c.1452109816.git.luto@kernel.org> <568ECF61.4040007@osg.samsung.com> <20160111105933.GA663@gmail.com> From: Andy Lutomirski Date: Mon, 11 Jan 2016 17:25:06 -0800 Message-ID: Subject: Re: [PATCH] selftests/x86: Disable ldt_gdt_64 for now To: Ingo Molnar Cc: Shuah Khan , Andy Lutomirski , X86 ML , Borislav Petkov , "linux-kernel@vger.kernel.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jan 11, 2016 at 2:59 AM, Ingo Molnar wrote: > > * 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? Oops, it applies on top of a new self-test that I forgot to send. I send a v2 that should be better. I'll send the new selftest out as well once -tip catches up with all the vdso patches. --Andy