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Date: Thu, 14 Aug 2003 15:31:29 -0500 (CDT)
From: Mike Silbersack <silby@silby.com>
To: John Baldwin <jhb@FreeBSD.org>
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Subject: RE: TCP socket shutdown race condition
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On Thu, 14 Aug 2003, John Baldwin wrote:

> In that case, CPU 2 uses an IPI to "push" the interrupt over to CPU 1
> since CPU 1 is in the kernel.  CPU 2 will not handle an interrupt unless
> it can get the giant lock.
>
> --
>
> John Baldwin <jhb@FreeBSD.org>  <><  http://www.FreeBSD.org/~jhb/

So on 4.x, any SMP race is probably also a UP race, but we just don't see
it because UP can't preempt.

Well, I guess the spl() fix is probably going to be the quickest here
then, please send it to me once you've pounded on it, Ed.

Mike "Silby" Silbersack