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From: Espen Skoglund <esk@ira.uka.de>
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Date: Fri, 28 Jan 2005 13:23:55 +0100
To: Christian Hildner <christian.hildner@hob.de>
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cc: freebsd-ia64@freebsd.org
Subject: Re: TLB miss handlers
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[Christian Hildner]
> Hi,
>     ld8 r21=[r21]       // check VHPT tag
>     ^^^^^^^^^^
> Are you sure you cannot enter a nested TLB miss fault here on IA64
> implementations that do not have the VHPT walker implemented? You
> wouldn't get fault 0x0000 since there is no walker that throws that
> fault.

Er... I can't remember seeing anywhere that implementing the VHPT
walker in the CPU is optional.  Anyhow, I'd imagine that the VHPT is
located in a place that is backed by a pinned TR.  But I'm not really
familiar with FreeBSD internals, so...

	eSk