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Date: Fri, 15 Aug 2003 23:01:50 -0400 (EDT)
From: Robert Watson <rwatson@freebsd.org>
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To: Kris Kennaway <kris@obsecurity.org>
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cc: current@freebsd.org
Subject: Re: LOR with filedesc structure and Giant
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On Fri, 15 Aug 2003, Kris Kennaway wrote:

> The problem seems to be due to select() being called on the /dev/null
> device, and it is holding the filedesc lock when it reaches
> PICKUP_GIANT() in spec_poll.

Yeah, this is pretty much the same issue you've been bumping into for a
bit -- we hold filedesc lock over select(), which means every object we
poll can't grab a lock that either comes before the file descriptor lockin
the lock order, or that might sleep.

Robert N M Watson             FreeBSD Core Team, TrustedBSD Projects
robert@fledge.watson.org      Network Associates Laboratories