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Date: Mon, 9 Aug 2004 16:52:15 -0400
From: Andrew Gallatin <gallatin@cs.duke.edu>
To: Brian Feldman <green@FreeBSD.org>
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	from green@FreeBSD.org on Mon, Aug 09, 2004 at 07:52:29PM +0000
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Subject: Re: cvs commit: src/sys/vm vm_kern.c vm_map.c vm_map.h
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Brian Feldman [green@FreeBSD.org] wrote:

>   * Require all mappings to be unwired before they are deleted.
>     When VM space is still wired upon deletion, it will be waited
>     upon for the following unwire.  This makes vslock(9) work
>     rather than allowing kernel-locked memory to be deleted
>     out from underneath of its consumer as it would before.

Can you explain in a little more detail what would happen now in the
following scenario:

An application running in userspace allocates SIZE bytes at "addr",
either with an mmap or via sbrk.  Then something in the kernel calls:
vm_map_wire(map, addr, addr + SIZE, TRUE) on its behalf.
Then the application frees (or munmaps) "addr".

Does the application sleep waiting for something to unwire addr+SIZE?

Thanks,

Drew