Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932451AbVIMI64 (ORCPT ); Tue, 13 Sep 2005 04:58:56 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932452AbVIMI64 (ORCPT ); Tue, 13 Sep 2005 04:58:56 -0400 Received: from liaag2ad.mx.compuserve.com ([149.174.40.155]:39888 "EHLO liaag2ad.mx.compuserve.com") by vger.kernel.org with ESMTP id S932451AbVIMI6z (ORCPT ); Tue, 13 Sep 2005 04:58:55 -0400 Date: Tue, 13 Sep 2005 04:55:41 -0400 From: Chuck Ebbert <76306.1226@compuserve.com> Subject: [patch 2.6.13] i386: Ignore masked FPU exceptions To: linux-kernel Cc: Andrew Morton , Linus Torvalds , Ondrej Zary Message-ID: <200509130458_MC3-1-AA03-D8AA@compuserve.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1261 Lines: 36 I think ignoring masked FPU exceptions on i386 is the right thing to do. Although there is no documentation available for Cyrix MII, I did find erratum F-7 for Winchip C6, "FPU instruction may result in spurious exception under certain conditions" which seems to indicate that this can happen. Ondrej, this patch on top of 2.6.13 should fix your Cyrix problems. Can you confirm? There was another bug which was already fixed, so this should be all that's needed now. Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com> arch/i386/kernel/traps.c | 5 +++-- 1 files changed, 3 insertions(+), 2 deletions(-) --- 2.6.13a.orig/arch/i386/kernel/traps.c +++ 2.6.13a/arch/i386/kernel/traps.c @@ -804,8 +804,9 @@ void math_error(void __user *eip) cwd = get_fpu_cwd(task); swd = get_fpu_swd(task); switch (swd & ~cwd & 0x3f) { - case 0x000: - default: + case 0x000: /* No unmasked exception */ + return; + default: /* Multiple exceptions */ break; case 0x001: /* Invalid Op */ /* __ Chuck - 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/