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Date: Fri, 04 May 2007 14:40:32 -0700
From: Julian Elischer <julian@elischer.org>
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To: John Baldwin <jhb@freebsd.org>
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Cc: attilio@freebsd.org, freebsd-current@freebsd.org,
	Harald Schmalzbauer <h.schmalzbauer@omnisec.de>
Subject: Re: PANIC: blockable slep lock (sx) msi @ ....msi.c:374
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John Baldwin wrote:

> 
> This is wrong because once you do critical_enter(), you are free to assume 
> that you won't do a context switch until you critical_exit(), and sx_xlock() 
> would violate that if it blocked on the lock.

wellllll critical enter doesn't block interupts so it's true if you don't call
an interrupt as a context switch.
(it doesn't SWITCH contexts but it does step into a different context.)

>