From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <005801c1be60$88bcd8a0$6401a8c0@attbi.com>
Reply-To: "Greg Griffes" <ggg@ieee.org>
From: "Greg Griffes" <ggg@ieee.org>
To: <linuxppc-embedded@lists.linuxppc.org>
References: <200202252229.g1PMTdQ02395@xdr.com>
Subject: Re: Linux 2.4.17 bug, mmap of /dev/mem
Date: Mon, 25 Feb 2002 19:57:15 -0500
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(snip)
> The crucial thing is mmap some region of io space
> read from a page write to the same page
> Repeat and rinse, something will corrupt the system.
>
> reads alone are ok.
> writes alone are ok.
> write followed by any combination of reads or writes is ok
> read followed by write = trouble

I am an embedded PPC Linux novice, so, tell me if I'm way off base.
This sounds like a pipeline problem; out of order I/O execution.
Could there be an "eieio" missing somewhere?

Greg Griffes


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