From owner-freebsd-current Mon Oct 28 00:35:03 1996 Return-Path: owner-current Received: (from root@localhost) by freefall.freebsd.org (8.7.5/8.7.3) id AAA12671 for current-outgoing; Mon, 28 Oct 1996 00:35:03 -0800 (PST) Received: from marble.eps.nagoya-u.ac.jp (marble.eps.nagoya-u.ac.jp [133.6.57.68]) by freefall.freebsd.org (8.7.5/8.7.3) with ESMTP id AAA12646 for ; Mon, 28 Oct 1996 00:34:39 -0800 (PST) Received: from marble.eps.nagoya-u.ac.jp (localhost [127.0.0.1]) by marble.eps.nagoya-u.ac.jp (8.7.6/3.4W4) with ESMTP id RAA02181; Mon, 28 Oct 1996 17:33:12 +0900 (JST) Message-Id: <199610280833.RAA02181@marble.eps.nagoya-u.ac.jp> To: kato@eclogite.eps.nagoya-u.ac.jp Cc: current@freebsd.org Subject: Re: patch for Cyrix/Ti 486SLC/DLC CPU bug In-Reply-To: Your message of "Wed, 11 Sep 1996 20:39:15 +0900" References: <199609111139.UAA00456@marble.eps.nagoya-u.ac.jp> X-Mailer: Mew version 1.05+ on Emacs 19.28.1, Mule 2.3 X-PGP-Fingerprint: 03 72 85 36 62 46 23 03 52 B1 10 22 44 10 0D 9E Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Date: Mon, 28 Oct 1996 17:33:11 +0900 From: KATO Takenori Sender: owner-current@freebsd.org X-Loop: FreeBSD.org Precedence: bulk On Wed, 11 Sep 1996 20:39:15 +0900, I said: > 1) FPU exception is handled by interrupt gate (machdep.c). ^^^^^^^^^^^^^ (page fault exception) > 2) The function trap gets fault page address as soon as possible > (trap.c). > 3) The functions pmap_update_{1,2}pg don't use LMSW instruction > but call pmap_update in cpufunc.h (pmap.c). > 1 and 2 are effective for strange signal 11, and 3 is for page fault. I got a report from a TI 486DLC2 user about the pmap_update problem (No. 3). He installed most recent FreeBSD-current, and his kernel doesn't panic. However, he said that page fault related problem still exists, and interruption should be disabled before getting page fault address on his machine. This problem rarely appears on my Cyrix 5x86 box. I added some debug code which shows rcr2() in the function trap(). When rcr2() returns zero, a process is terminated by signal 11. ---- KATO Takenori Dept. Earth Planet. Sci., Nagoya Univ., Nagoya, 464-01, Japan PGP public key: finger kato@eclogite.eps.nagoya-u.ac.jp