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Date:      Thu, 19 Apr 2001 16:47:52 +0000 (GMT)
From:      Terry Lambert <tlambert@primenet.com>
To:        dillon@earth.backplane.com (Matt Dillon)
Cc:        bde@zeta.org.au (Bruce Evans), tlambert@primenet.com (Terry Lambert), arch@FreeBSD.ORG
Subject:   Re: Found BAD BUG: squashed
Message-ID:  <200104191647.JAA02940@usr08.primenet.com>
In-Reply-To: <200104190755.f3J7taQ51976@earth.backplane.com> from "Matt Dillon" at Apr 19, 2001 12:55:36 AM

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>     Ok.  Since -current went from u_short to u_int, we should simply MFC
>     that change to stable after 4.3 is out the door.  Now, I know you have
>     your heart set on your fancy overflow check Terry but I really think
>     going to a 32 bit counter is the best solution, especially as Bruce
>     pointed out it will not bloat the structure.  We've been moving all our
>     other ref counts to 32 bits over the years...

Note that Bruce's fix doesn't addres the invariant stomping the
reference count, which makes checking for multiple frees
impossible.  The only way to fix that is to move the cr_ref out
of the first two bytes.


I would still like a general reference counting mechanism, so
I could turn on overflow checking at runtime.

As I said before, this is independent of whether the cred is
duplicated near overflow, or the count pushes the overflow off
to 4 billion (without preventing it).


					Terry Lambert
					terry@lambert.org
---
Any opinions in this posting are my own and not those of my present
or previous employers.

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