From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261210AbULWL3l (ORCPT ); Thu, 23 Dec 2004 06:29:41 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261212AbULWL3l (ORCPT ); Thu, 23 Dec 2004 06:29:41 -0500 Received: from cantor.suse.de ([195.135.220.2]:30408 "EHLO Cantor.suse.de") by vger.kernel.org with ESMTP id S261210AbULWL3k (ORCPT ); Thu, 23 Dec 2004 06:29:40 -0500 Date: Thu, 23 Dec 2004 12:29:39 +0100 From: Andi Kleen To: Bodo Stroesser Cc: Andi Kleen , linux-kernel@vger.kernel.org Subject: Re: 2.6.10-rc3, i386: fpu handling on sigreturn Message-ID: <20041223112939.GG14560@wotan.suse.de> References: <41C9B21F.90802@fujitsu-siemens.com.suse.lists.linux.kernel> <41CA0813.1070707@fujitsu-siemens.com> <20041222235448.GA17720@verdi.suse.de> <41CA90F4.8000800@fujitsu-siemens.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <41CA90F4.8000800@fujitsu-siemens.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > Sorry, I don't agree. AFAICS, if used_math isn't reset, on the next > attempt of the process to use the fpu, it will be reloaded with the > values, that come from the sighandler and that still reside in > thread.i387. Thus, clear_cpu() without resetting used_math has no > effect to the userspace task. > Resetting current->used_math to 0 would make math_state_restore() > calling init_fpu(), that clears thread.i387 before the fpu is loaded. Ok I agree. I revised the patch here. -Andi