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Date: Fri, 15 Aug 2008 21:51:15 -0600
From: Scott Long <scottl@samsco.org>
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Cc: freebsd-current@freebsd.org
Subject: Re: kernel memory
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vehemens wrote:
> I'm going to ask this question as I have not seen this rule written down 
> anywhere.  So don't shoot me please :>
> 
> Do kernel memory memory routines such as malloc always return a region of 
> memory that is locked to a physical page?

Malloc does, yes, as does the UMA zone allocator.  If all you want is an
virtual address range, but no backing pages, use
kmem_alloc_nofault(kernel_map, size).  To later associate it with a
physical page, you can use something like pmap_kenter(va, pa)

Scott