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To: 9fans@9fans.net
Date: Wed, 14 May 2008 02:12:45 +0200
From: cinap_lenrek@gmx.de
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Subject: Re: [9fans] some x86 Segment descriptor experiments
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arrrg... i found the problem... of course! Plan9 *does* restore/reload the
segment registers! It does it still in kernel mode. So if a segment
register is set (from usermode) with a selector pointing to my TLS
descriptor, and that descriptor gets changed to {0, 0} again, forkret()
restores/reloads the segment register and *kernel* gets a GP fault.

Now the selector checking in trap() makes sense... arrg >_<

sorry for the noise...

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Date: Tue, 13 May 2008 16:26:31 -0700
From: "ron minnich" <rminnich@gmail.com>
To: "Fans of the OS Plan 9 from Bell Labs" <9fans@9fans.net>
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Subject: Re: [9fans] some x86 Segment descriptor experiments
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it seems reasonable on first glance. What's the stack barf look like?

ron
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