From owner-freebsd-hackers  Fri Aug  3 11:35:34 2001
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Date: Fri, 3 Aug 2001 14:34:17 -0400 (EDT)
From: Zhihui Zhang <zzhang@cs.binghamton.edu>
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To: freebsd-hackers@FreeBSD.ORG
Subject: Re: Allocate a page at interrupt time
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I should have guessed the reason. Matthew Dillon answered this question on	
Fri, 2 Jun 2000 as follows:


    The VM routines that manage pages associated with objects are not
    protected against interrupts, so interrupts aren't allowed to change
    page-object associations.  Otherwise an interrupt at just the wrong
    time could corrupt the mainline kernel VM code.


On Thu, 2 Aug 2001, Zhihui Zhang wrote:

> 
> FreeBSD can not allocate from the PQ_CACHE queue in an interrupt context.
> Can anyone explain it to me why this is the case?
> 
> 
> Thanks,


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