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Date: Tue, 03 Jun 2003 22:56:00 -0700
From: Terry Lambert <tlambert2@mindspring.com>
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To: Scott Long <scottl@freebsd.org>
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cc: Bryan Liesner <bleez@verizon.net>
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cc: Jeff Roberson <jroberson@chesapeake.net>
Subject: Re: umtx/libthr SMP fixes.
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Scott Long wrote:
> Bryan Liesner wrote:
> It's very hard to imagine Jeff's patches causing a problem at the point
> that the PR mentions.  Have you confirmed the problem in a kernel that
> was build in a totally clean environment?

The changed code is not protecting a traversal of a proc
struct member with a proc lock in two places.  What's hard
to imagine?

Even if it's weren't necessary to protect that FOREACH loop
(it's necessary; but even if it weren't...), locking the
proc could easily serialize a number of operations through
that or other code which could save it from interference.

-- Terry