From owner-svn-src-all@FreeBSD.ORG Wed Jan 19 17:18:22 2011 Return-Path: Delivered-To: svn-src-all@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id F2F311065673; Wed, 19 Jan 2011 17:18:21 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from mail.zoral.com.ua (mx0.zoral.com.ua [91.193.166.200]) by mx1.freebsd.org (Postfix) with ESMTP id 4A7838FC0A; Wed, 19 Jan 2011 17:18:20 +0000 (UTC) Received: from deviant.kiev.zoral.com.ua (root@deviant.kiev.zoral.com.ua [10.1.1.148]) by mail.zoral.com.ua (8.14.2/8.14.2) with ESMTP id p0JHI729006337 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Wed, 19 Jan 2011 19:18:07 +0200 (EET) (envelope-from kostikbel@gmail.com) Received: from deviant.kiev.zoral.com.ua (kostik@localhost [127.0.0.1]) by deviant.kiev.zoral.com.ua (8.14.4/8.14.4) with ESMTP id p0JHI7wI019294; Wed, 19 Jan 2011 19:18:07 +0200 (EET) (envelope-from kostikbel@gmail.com) Received: (from kostik@localhost) by deviant.kiev.zoral.com.ua (8.14.4/8.14.4/Submit) id p0JHI7w2019293; Wed, 19 Jan 2011 19:18:07 +0200 (EET) (envelope-from kostikbel@gmail.com) X-Authentication-Warning: deviant.kiev.zoral.com.ua: kostik set sender to kostikbel@gmail.com using -f Date: Wed, 19 Jan 2011 19:18:07 +0200 From: Kostik Belousov To: Jung-uk Kim Message-ID: <20110119171807.GA2518@deviant.kiev.zoral.com.ua> References: <201101191709.p0JH97ZD083132@svn.freebsd.org> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="cr8px54RfQr1fJtZ" Content-Disposition: inline In-Reply-To: <201101191709.p0JH97ZD083132@svn.freebsd.org> User-Agent: Mutt/1.4.2.3i X-Virus-Scanned: clamav-milter 0.95.2 at skuns.kiev.zoral.com.ua X-Virus-Status: Clean X-Spam-Status: No, score=-3.4 required=5.0 tests=ALL_TRUSTED,AWL,BAYES_00, DNS_FROM_OPENWHOIS autolearn=no version=3.2.5 X-Spam-Checker-Version: SpamAssassin 3.2.5 (2008-06-10) on skuns.kiev.zoral.com.ua Cc: svn-src-head@freebsd.org, svn-src-all@freebsd.org, src-committers@freebsd.org Subject: Re: svn commit: r217587 - head/sys/i386/i386 X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 19 Jan 2011 17:18:22 -0000 --cr8px54RfQr1fJtZ Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Jan 19, 2011 at 05:09:07PM +0000, Jung-uk Kim wrote: > Author: jkim > Date: Wed Jan 19 17:09:07 2011 > New Revision: 217587 > URL: http://svn.freebsd.org/changeset/base/217587 >=20 > Log: > Fix yet another fallout from r208833. VM86 BIOS call may cause page fa= ult > when FPU is in use. > =20 > Reported by: Marc UBM Bocklet (ubm dot freebsd at googlemail dot com) > Tested by: b. f. (bf1783 at googlemail dot com) > MFC after: 3 days >=20 > Modified: > head/sys/i386/i386/vm86bios.s >=20 > Modified: head/sys/i386/i386/vm86bios.s > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D > --- head/sys/i386/i386/vm86bios.s Wed Jan 19 17:04:07 2011 (r217586) > +++ head/sys/i386/i386/vm86bios.s Wed Jan 19 17:09:07 2011 (r217587) > @@ -73,10 +73,9 @@ ENTRY(vm86_bioscall) > je 1f /* no curproc/npxproc */ > pushl %edx > movl TD_PCB(%ecx),%ecx > - addl $PCB_SAVEFPU,%ecx > - pushl %ecx > + pushl PCB_SAVEFPU(%ecx) > call npxsave > - popl %ecx > + addl $4,%esp > popl %edx /* recover our pcb */ > 1: > popfl vm86_bioscall() in fact inlines the old version of npxexit(). Shouldn't the npxexit() be called from C code before call to vm86_bioscall ? Also, if bioscall can be used from the syscall context, I think whatever npxsave()/npxexit() is used, and BIOS modifies FPU state, we are corrupting usermode FPU context. Probably, fpu_kern_enter()/fpu_kern_leave() braces around vm86_bioscall is proper solution. --cr8px54RfQr1fJtZ Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (FreeBSD) iEYEARECAAYFAk03HM4ACgkQC3+MBN1Mb4gPWQCfTYpj25dyrceaOrmyYExO+Bpm uUMAoIUUH5eMvveKA7peZujUuRfBSJCE =WeQF -----END PGP SIGNATURE----- --cr8px54RfQr1fJtZ--