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Date: Mon, 06 Sep 2010 00:49:35 -0500
From: Alan Cox <alan.l.cox@gmail.com>
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Cc: freebsd-hackers@freebsd.org, Nathan Whitehorn <nwhitehorn@freebsd.org>
Subject: Re: UMA allocations from a specific physical range
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mdf@FreeBSD.org wrote:
[snip]
> IIRC the memory from vm_phys_alloc_contig() can be released like any
> other page; the interface should just be fetching a specific page.
> How far off is the page wire count?  I'm assuming it's hitting the
> assert that it's > 1?
>
> I think vm_page_free() is the right interface to free the page again,
> so the wire count being off presumably means someone else wired it on
> you; do you know what code did it?  If no one else has a reference to
> the page anymore then setting the wire count to 1, while a hack,
> should be safe.
>
>   

Yes, vm_page_free() can be used to free a single page that was returned 
by vm_phys_alloc_contig().

Alan