Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760229Ab2HXVQa (ORCPT ); Fri, 24 Aug 2012 17:16:30 -0400 Received: from mga03.intel.com ([143.182.124.21]:7595 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751785Ab2HXVPa (ORCPT ); Fri, 24 Aug 2012 17:15:30 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.80,304,1344236400"; d="scan'208";a="190967378" From: Suresh Siddha To: hpa@zytor.com, mingo@kernel.org, torvalds@linux-foundation.org, andreas.herrmann3@amd.com, bp@amd64.org, robert.richter@amd.com Cc: linux-kernel@vger.kernel.org, Suresh Siddha Subject: [PATCH 1/6] x86, fpu: drop_fpu() before restoring new state from sigframe Date: Fri, 24 Aug 2012 14:12:57 -0700 Message-Id: <1345842782-24175-2-git-send-email-suresh.b.siddha@intel.com> X-Mailer: git-send-email 1.7.6.5 In-Reply-To: <1345842782-24175-1-git-send-email-suresh.b.siddha@intel.com> References: <1345842782-24175-1-git-send-email-suresh.b.siddha@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2088 Lines: 67 No need to save the state with unlazy_fpu(), that is about to get overwritten by the state from the signal frame. Instead use drop_fpu() and continue to restore the new state. Also fold the stop_fpu_preload() into drop_fpu(). Signed-off-by: Suresh Siddha --- arch/x86/include/asm/fpu-internal.h | 7 +------ arch/x86/kernel/xsave.c | 8 +++----- 2 files changed, 4 insertions(+), 11 deletions(-) diff --git a/arch/x86/include/asm/fpu-internal.h b/arch/x86/include/asm/fpu-internal.h index ba83a08..fe95ad0 100644 --- a/arch/x86/include/asm/fpu-internal.h +++ b/arch/x86/include/asm/fpu-internal.h @@ -448,17 +448,12 @@ static inline void save_init_fpu(struct task_struct *tsk) preempt_enable(); } -static inline void stop_fpu_preload(struct task_struct *tsk) -{ - tsk->fpu_counter = 0; -} - static inline void drop_fpu(struct task_struct *tsk) { /* * Forget coprocessor state.. */ - stop_fpu_preload(tsk); + tsk->fpu_counter = 0; preempt_disable(); __drop_fpu(tsk); preempt_enable(); diff --git a/arch/x86/kernel/xsave.c b/arch/x86/kernel/xsave.c index a23d100..6cfc7d9 100644 --- a/arch/x86/kernel/xsave.c +++ b/arch/x86/kernel/xsave.c @@ -381,16 +381,14 @@ int __restore_xstate_sig(void __user *buf, void __user *buf_fx, int size) struct xsave_struct *xsave = &tsk->thread.fpu.state->xsave; struct user_i387_ia32_struct env; - stop_fpu_preload(tsk); - unlazy_fpu(tsk); + drop_fpu(tsk); if (__copy_from_user(xsave, buf_fx, state_size) || - __copy_from_user(&env, buf, sizeof(env))) { - drop_fpu(tsk); + __copy_from_user(&env, buf, sizeof(env))) return -1; - } sanitize_restored_xstate(tsk, &env, xstate_bv, fx_only); + set_used_math(); } else { /* * For 64-bit frames and 32-bit fsave frames, restore the user -- 1.7.6.5 -- 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/