To: Carlos Munoz <carlos@kenati.com>
Cc: Lee Revell <rlrevell@joe-job.com>, Valdis.Kletnieks@vt.edu,
       linux-kernel@vger.kernel.org
Subject: Re: How can I link the kernel with libgcc ?
References: <4410D9F0.6010707@kenati.com>
	<200603100145.k2A1jMem005323@turing-police.cc.vt.edu>
	<1141956362.13319.105.camel@mindpipe> <4410EC0D.3090303@kenati.com>
	<4410F1BE.7000904@kenati.com>
From: Jes Sorensen <jes@sgi.com>
Date: 10 Mar 2006 05:18:41 -0500
In-Reply-To: <4410F1BE.7000904@kenati.com>
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>>>>> "Carlos" == Carlos Munoz <carlos@kenati.com> writes:

Carlos> I figured out how to get the driver to use floating point
Carlos> operations. I included source code (from an open source math
Carlos> library) for the log10 function in the driver. Then I added
Carlos> the following lines to the file arch/sh/kernel/sh_ksyms.c:

Bad bad bad!

You shouldn't be using floating point in the kernel at all! Most
architectures do not save the full floating point register set on
entry so if you start messing with the fp registers you may corrupt
user space applications.

You need to either write a customer user space app or use a table as
Arjan suggested.

Cheers,
Jes
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