From owner-cvs-all@FreeBSD.ORG  Fri Jun 18 04:02:47 2004
Return-Path: <owner-cvs-all@FreeBSD.ORG>
Delivered-To: cvs-all@freebsd.org
Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125])
	by hub.freebsd.org (Postfix) with ESMTP
	id 0D55316A4CE; Fri, 18 Jun 2004 04:02:47 +0000 (GMT)
Received: from repoman.freebsd.org (repoman.freebsd.org [216.136.204.115])
	by mx1.FreeBSD.org (Postfix) with ESMTP
	id 062CB43D2D; Fri, 18 Jun 2004 04:02:47 +0000 (GMT)
	(envelope-from peter@FreeBSD.org)
Received: from repoman.freebsd.org (localhost [127.0.0.1])
	by repoman.freebsd.org (8.12.11/8.12.11) with ESMTP id i5I41sXo000425;
	Fri, 18 Jun 2004 04:01:54 GMT
	(envelope-from peter@repoman.freebsd.org)
Received: (from peter@localhost)
	by repoman.freebsd.org (8.12.11/8.12.11/Submit) id i5I41sZf000421;
	Fri, 18 Jun 2004 04:01:54 GMT
	(envelope-from peter)
Message-Id: <200406180401.i5I41sZf000421@repoman.freebsd.org>
From: Peter Wemm <peter@FreeBSD.org>
Date: Fri, 18 Jun 2004 04:01:54 +0000 (UTC)
To: src-committers@FreeBSD.org, cvs-src@FreeBSD.org,
	cvs-all@FreeBSD.org
X-FreeBSD-CVS-Branch: HEAD
Subject: cvs commit: src/sys/amd64/amd64 fpu.c
X-BeenThere: cvs-all@freebsd.org
X-Mailman-Version: 2.1.1
Precedence: list
List-Id: CVS commit messages for the entire tree <cvs-all.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/cvs-all>,
	<mailto:cvs-all-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/cvs-all>
List-Post: <mailto:cvs-all@freebsd.org>
List-Help: <mailto:cvs-all-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/cvs-all>,
	<mailto:cvs-all-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Fri, 18 Jun 2004 04:02:47 -0000

peter       2004-06-18 04:01:54 UTC

  FreeBSD src repository

  Modified files:
    sys/amd64/amd64      fpu.c 
  Log:
  Try harder to give new processes a clean initial fpu state.  fpu_cleanstate
  wasn't actually clean, it was saving the xmm registers as left over by the
  bios.  fninit() doesn't clear those.
  
  In fpudna(), instead of doing a fninit() and forgetting to load the initial
  mxcsr, do a full fxrstor(&fpu_cleanstate).  Otherwise we hand over whatever
  random values are left in the xmm registers by the last user.
  
  I'm not certain of whether this is excessive paranoia or not, but there was
  an outright bug in neglecting to set the mxcsr value that caused awk to
  SIGFPE in some case.  Especially for Tim Robbins. :-)
  
  i386 probably should do something about the mxcsr setings too.
  
  Found by:  tjr
  
  Revision  Changes    Path
  1.154     +5 -7      src/sys/amd64/amd64/fpu.c