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Date: Sun, 21 Jan 1996 23:54:09 +1100
From: Bruce Evans <bde@zeta.org.au>
Message-Id: <199601211254.XAA10974@godzilla.zeta.org.au>
To: brians@mandor.dev.com, freebsd-hackers@FreeBSD.ORG
Subject: Re: USER_LDT limit
Sender: owner-hackers@FreeBSD.ORG
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>I'm playing with Wine for FreeBSD 2.1, and found something odd.  In
>/usr/src/sys/i386/i386/sys_machdep.c, I see that the descriptor maximum
>allowed in i386_set_ldt() is 512, which isn't strange.  What is surprising
>is that it isn't a macro define.  Is the number 512 magic? I'd like to

I think it is just bad programming.  The power of 2 size is good for
avoiding memory wastage.  However, malloc() would better than kmem_malloc()
here since malloc() provides statistics.  However^2, the amount of memory
is fairly large and it is per-process, so it should be pageable.  Can
the vm system page user LDT's?

Bruce