Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762690AbbEESNt (ORCPT ); Tue, 5 May 2015 14:13:49 -0400 Received: from mail-wi0-f169.google.com ([209.85.212.169]:34345 "EHLO mail-wi0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1161472AbbEER7N (ORCPT ); Tue, 5 May 2015 13:59:13 -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 172/208] x86/fpu: Clarify ancient comments in fpu__restore() Date: Tue, 5 May 2015 19:57:56 +0200 Message-Id: <1430848712-28064-12-git-send-email-mingo@kernel.org> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1430848712-28064-1-git-send-email-mingo@kernel.org> References: <1430848712-28064-1-git-send-email-mingo@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2041 Lines: 54 So this function still had ancient language about 'saving current math information' - but we haven't been doing lazy FPU saves for quite some time, we are doing lazy FPU restores. Also remove IRQ13 related comment, which we don't support anymore either. Cc: Andy Lutomirski Cc: Borislav Petkov 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/fpu/core.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c index 7e91a6f7564a..45ef4e51928b 100644 --- a/arch/x86/kernel/fpu/core.c +++ b/arch/x86/kernel/fpu/core.c @@ -319,14 +319,14 @@ static void fpu__activate_stopped(struct fpu *child_fpu) } /* - * 'fpu__restore()' saves the current math information in the - * old math state array, and gets the new ones from the current task + * 'fpu__restore()' is called to copy FPU registers from + * the FPU fpstate to the live hw registers and to activate + * access to the hardware registers, so that FPU instructions + * can be used afterwards. * - * Careful.. There are problems with IBM-designed IRQ13 behaviour. - * Don't touch unless you *really* know how it works. - * - * Must be called with kernel preemption disabled (eg with local - * local interrupts as in the case of do_device_not_available). + * Must be called with kernel preemption disabled (for example + * with local interrupts disabled, as it is in the case of + * do_device_not_available()). */ void fpu__restore(void) { -- 2.1.0 -- 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/