From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <0c7ec36d740f732994044bd3bfc4a61b@quanstro.net>
From: erik quanstrom <quanstro@quanstro.net>
Date: Wed,  2 Sep 2009 09:35:26 -0400
To: 9fans@9fans.net
In-Reply-To: <9ab217670909020628t15f58a3bj99210c287fa5e298@mail.gmail.com>
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Subject: Re: [9fans] lowest valid stack address
Topicbox-Message-UUID: 5ec40b4e-ead5-11e9-9d60-3106f5b1d025

> problem ended up being that I'd have to rework a lot of the slab
> allocator, or do checks on every memory allocation, and I didn't want
> to do that. More detailed info for those who care:

could you use plan 9 terminology?

>
> Lemma: In order to avoid overcommitting, we must impose limits on how
> much memory may, in fact, be allocated. To make the implementation
> provable, you must be able to assert that memory always comes from the
> same spot, and you thus have a single path to follow into allocation.

"from the same spot" could mean from the same point in the code or
from the same physical address.  either way, i don't buy this assertion.
counter example: ssd drive remapping algorithms.

- erik