From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <13426df10708221602l51238c48x2e4d6999891fc158@mail.gmail.com>
Date: Wed, 22 Aug 2007 19:02:08 -0400
From: "ron minnich" <rminnich@gmail.com>
To: "Fans of the OS Plan 9 from Bell Labs" <9fans@cse.psu.edu>
Subject: Re: [9fans] double-mapping KZERO in l.s
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On 8/22/07, erik quanstrom <quanstro@coraid.com> wrote:
> perhaps this is completely obvious, but why are the first
> 4 mb double-mapped in l.s at virtual address 0 and KZERO?
>

you start out executing with real memory addresses, i.e. you are
executing code at 0x100000 not at KZERO+0x100000. There is a period of
time where you are executing at those low addresses, then you pop up
to KZERO space and you blow away the low mappings by clearing
PDO(KZERO).

ron