From owner-freebsd-hackers Fri Mar 9 19:34:43 2001 Delivered-To: freebsd-hackers@freebsd.org Received: from xena.gsicomp.on.ca (cr677933-a.ktchnr1.on.wave.home.com [24.43.230.149]) by hub.freebsd.org (Postfix) with ESMTP id 82BF237B71C for ; Fri, 9 Mar 2001 19:34:40 -0800 (PST) (envelope-from matt@gsicomp.on.ca) Received: from hermes (hermes.gsicomp.on.ca [192.168.0.18]) by xena.gsicomp.on.ca (8.11.1/8.9.3) with SMTP id f2A3Wsi49550; Fri, 9 Mar 2001 22:32:54 -0500 (EST) (envelope-from matt@gsicomp.on.ca) Message-ID: <003d01c0a913$923455b0$1200a8c0@gsicomp.on.ca> From: "Matthew Emmerton" To: "Matthew Emmerton" , References: <000b01c0a90a$e3287360$1200a8c0@gsicomp.on.ca> Subject: Re: Kernel area libmish stuff Date: Fri, 9 Mar 2001 22:38:28 -0500 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4133.2400 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4133.2400 Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG > > On Fri, 9 Mar 2001, Matt Dillon wrote: > > > > > You can't safely do FP instructions in the kernel. I do not > > > believe the FP context is saved/restored between processes in kernel > > > mode, only from user mode. The kernel saves and restores the fp > state > > > in the few places it uses FP instructions (for memory copying). > > > In anycase, I think there'd be a problem here. > > > > The last time I tried using FP in a device driver, it caused kernel > > panics (I hate it when that happens...) > > Seeing as the original requestor wanted to use FP functions to do number > crunching in screen savers, would adding a few strategic FP save/restore > calls in the syscons driver be enough to allow FP calculations in screen > saver modules? Please forget I ever said this. I took a look at what would be involved, and it's wayyyy too deep for me to even begin about thinking about it. -- Matt Emmerton To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message