From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933756AbbEERJF (ORCPT ); Tue, 5 May 2015 13:09:05 -0400 Received: from mail-wi0-f179.google.com ([209.85.212.179]:36327 "EHLO mail-wi0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760639AbbEEQ1n (ORCPT ); Tue, 5 May 2015 12:27:43 -0400 From: Ingo Molnar To: linux-kernel@vger.kernel.org Cc: Andy Lutomirski , Borislav Petkov , Dave Hansen , Fenghua Yu , "H. Peter Anvin" , Linus Torvalds , Oleg Nesterov , Thomas Gleixner Subject: [PATCH 003/208] x86/fpu: Add debugging check to fpu__save() Date: Tue, 5 May 2015 18:23:43 +0200 Message-Id: <1430843228-13749-4-git-send-email-mingo@kernel.org> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1430843228-13749-1-git-send-email-mingo@kernel.org> References: <1430843228-13749-1-git-send-email-mingo@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Document the function a bit more and add debugging check that we are only running this with the current task. Reviewed-by: Borislav Petkov Cc: Andy Lutomirski Cc: Dave Hansen Cc: Fenghua Yu Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Oleg Nesterov Cc: Thomas Gleixner Signed-off-by: Ingo Molnar --- arch/x86/kernel/i387.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/x86/kernel/i387.c b/arch/x86/kernel/i387.c index ac47278cde71..66f1053ae2cd 100644 --- a/arch/x86/kernel/i387.c +++ b/arch/x86/kernel/i387.c @@ -119,9 +119,13 @@ EXPORT_SYMBOL(__kernel_fpu_end); /* * Save the FPU state (initialize it if necessary): + * + * This only ever gets called for the current task. */ void fpu__save(struct task_struct *tsk) { + WARN_ON(tsk != current); + preempt_disable(); if (__thread_has_fpu(tsk)) { if (use_eager_fpu()) { -- 2.1.0