From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754710AbcHUPu7 (ORCPT ); Sun, 21 Aug 2016 11:50:59 -0400 Received: from wtarreau.pck.nerim.net ([62.212.114.60]:55778 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754400AbcHUPes (ORCPT ); Sun, 21 Aug 2016 11:34:48 -0400 From: Willy Tarreau To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Russell King , Willy Tarreau Subject: [PATCH 3.10 094/180] ARM: fix PTRACE_SETVFPREGS on SMP systems Date: Sun, 21 Aug 2016 17:30:24 +0200 Message-Id: <1471793510-13022-95-git-send-email-w@1wt.eu> X-Mailer: git-send-email 2.8.0.rc2.1.gbe9624a In-Reply-To: <1471793510-13022-1-git-send-email-w@1wt.eu> References: <1471793510-13022-1-git-send-email-w@1wt.eu> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Russell King commit e2dfb4b880146bfd4b6aa8e138c0205407cebbaf upstream. PTRACE_SETVFPREGS fails to properly mark the VFP register set to be reloaded, because it undoes one of the effects of vfp_flush_hwstate(). Specifically vfp_flush_hwstate() sets thread->vfpstate.hard.cpu to an invalid CPU number, but vfp_set() overwrites this with the original CPU number, thereby rendering the hardware state as apparently "valid", even though the software state is more recent. Fix this by reverting the previous change. Cc: Fixes: 8130b9d7b9d8 ("ARM: 7308/1: vfp: flush thread hwstate before copying ptrace registers") Acked-by: Will Deacon Tested-by: Simon Marchi Signed-off-by: Russell King Signed-off-by: Willy Tarreau --- arch/arm/kernel/ptrace.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm/kernel/ptrace.c b/arch/arm/kernel/ptrace.c index 03deeff..4e2110d 100644 --- a/arch/arm/kernel/ptrace.c +++ b/arch/arm/kernel/ptrace.c @@ -733,8 +733,8 @@ static int vfp_set(struct task_struct *target, if (ret) return ret; - vfp_flush_hwstate(thread); thread->vfpstate.hard = new_vfp; + vfp_flush_hwstate(thread); return 0; } -- 2.8.0.rc2.1.gbe9624a