From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 932F9C169C4 for ; Sun, 3 Feb 2019 14:03:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6BA9120815 for ; Sun, 3 Feb 2019 14:03:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729706AbfBCODA (ORCPT ); Sun, 3 Feb 2019 09:03:00 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:54794 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728051AbfBCOC5 (ORCPT ); Sun, 3 Feb 2019 09:02:57 -0500 Received: from cable-78.29.236.164.coditel.net ([78.29.236.164] helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1gqIEO-0003th-Lb; Sun, 03 Feb 2019 13:54:44 +0000 Received: from ben by deadeye with local (Exim 4.92-RC4) (envelope-from ) id 1gqIEL-0000BQ-AM; Sun, 03 Feb 2019 14:54:41 +0100 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, Denis Kirjanov , "Peter Zijlstra" , "Thomas Gleixner" , "Andy Lutomirski" , "Matthew Whitehead" , "Ingo Molnar" , "Linus Torvalds" Date: Sun, 03 Feb 2019 14:45:08 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 305/305] x86/vdso: Fix vDSO syscall fallback asm constraint regression In-Reply-To: X-SA-Exim-Connect-IP: 78.29.236.164 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.63-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Andy Lutomirski commit 02e425668f5c9deb42787d10001a3b605993ad15 upstream. When I added the missing memory outputs, I failed to update the index of the first argument (ebx) on 32-bit builds, which broke the fallbacks. Somehow I must have screwed up my testing or gotten lucky. Add another test to cover gettimeofday() as well. Signed-off-by: Andy Lutomirski Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Fixes: 715bd9d12f84 ("x86/vdso: Fix asm constraints on vDSO syscall fallbacks") Link: http://lkml.kernel.org/r/21bd45ab04b6d838278fa5bebfa9163eceffa13c.1538608971.git.luto@kernel.org Signed-off-by: Ingo Molnar [bwh: Backported to 3.16: - Drop selftest changes - Adjust filename] Tested-by: Matthew Whitehead Signed-off-by: Ben Hutchings --- arch/x86/vdso/vclock_gettime.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- a/arch/x86/vdso/vclock_gettime.c +++ b/arch/x86/vdso/vclock_gettime.c @@ -147,11 +147,11 @@ notrace static long vdso_fallback_gettim asm ( "mov %%ebx, %%edx \n" - "mov %2, %%ebx \n" + "mov %[clock], %%ebx \n" "call __kernel_vsyscall \n" "mov %%edx, %%ebx \n" : "=a" (ret), "=m" (*ts) - : "0" (__NR_clock_gettime), "g" (clock), "c" (ts) + : "0" (__NR_clock_gettime), [clock] "g" (clock), "c" (ts) : "memory", "edx"); return ret; } @@ -162,11 +162,11 @@ notrace static long vdso_fallback_gtod(s asm ( "mov %%ebx, %%edx \n" - "mov %2, %%ebx \n" + "mov %[tv], %%ebx \n" "call __kernel_vsyscall \n" "mov %%edx, %%ebx \n" : "=a" (ret), "=m" (*tv), "=m" (*tz) - : "0" (__NR_gettimeofday), "g" (tv), "c" (tz) + : "0" (__NR_gettimeofday), [tv] "g" (tv), "c" (tz) : "memory", "edx"); return ret; }