From owner-freebsd-hackers  Fri Oct 12  9: 5:34 2001
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Date: Fri, 12 Oct 2001 18:05:15 +0200
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From: Patrick Cipiere <Patrick.Cipiere@UDcast.com>
To: tinguely@web.cs.ndsu.nodak.edu
Cc: dillon@earth.backplane.com, Patrick.Cipiere@UDcast.com,
	freebsd-hackers@FreeBSD.ORG
In-reply-to: <200110121501.f9CF17Y14052@web.cs.ndsu.nodak.edu> (message from
	mark tinguely on Fri, 12 Oct 2001 10:01:07 -0500 (CDT))
Subject: Re: contigfree, free what?
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Mark,

> I also placed some checks on vm_map_delete

I did that also, and as far as I understand everything works fine.
The only thing I found was the fact that when contigmalloc() grabs the
contig pages it sets the value of pga[i] (for i in allocated pages)
note that: vm_page_t pga = vm_page_array;

Then contigfree() does a pretty good job, but does not reset the values
of pga[i] to pqtype == PQ_FREE (pqtype = pga[i].queue - pga[i].pc)

So the next contigmalloc() requiring the same number of pages fails on
the previously released pages because they are not PQ_FREE

The other thing that puzzled me is the fact that in vm_map_delete()
called by contgigfree() has a variable

  object = entry->object.vm_object;

which shows a value of 0 rather than kernel_object or kmem_object

But my understanding might be wrong.

Thanks,
Patrick.
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