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From: "Michael Neubauer" <neubauer@in.tum.de>
Date: Thu, 29 Mar 2007 11:58:33 +0200
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Subject: [Qemu-devel] Qemu memory management
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To: qemu-devel@nongnu.org

Hello,

I'm trying to learn a bit more about the Qemu SoftMMU. The following
quotation is taken from section 2.10 of the "Qemu Internals" documentation.

"To avoid flushing the translated code each time the MMU mappings change,
QEMU uses a physically indexed translation cache. It means that each TB is
indexed with its physical address." 

Why does a cache like that prevent the translated code from being flushed?
If a translated code is relocated in physical memory (e. g. after a paging
swap operation) that would render the cache useless in my opinion. Maybe I'm
just mixing too many things up here since I don't really have a lot of
experience in the whole operating systems stuff. I would really appreciate
it if someone could give me a hint.

I'm sorry if that's the wrong place to ask questions like the one above.
Please let me know if there's any other  comprehensive resource of
information available.

-- Michael