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Subject: Re: How should a driver shutdown a taskqueue on detach?
From: Ryan Stone <rysto32@gmail.com>
To: Jack Vogel <jfvogel@gmail.com>
Cc: FreeBSD Current <freebsd-current@freebsd.org>
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On Wed, Jul 1, 2015 at 4:58 PM, Jack Vogel <jfvogel@gmail.com> wrote:

> But if you've disabled interrupts why would an "interrupt-handling task"
> even run??
>
> Jack
>

There's a race.  The task could have already have been scheduled by a
previous interrupt and could be running while I am trying to disable
interrupts and drain the taskqueue.