More mbuf INVARIANTS code, comments needed

Mike Silbersack silby at silby.com
Fri May 2 18:38:38 PDT 2003


On Fri, 2 May 2003, Vincent Jardin wrote:

> It is a good idea. I do not see any problems with your patch.
>
> An esthetic comment:
> I would prefer to see other trivial hexadecimal values like:
>   - 0xd0 (as in "Duh", used by stdlib/malloc())
>   - or 0xdeadc0de (used by kern_malloc.c:#define WEIRD_ADDR  0xdeadc0de)
>   - or 0xdead0137, 0xdead0138, 0xdead0139, ...
>
> According to me, these values are easier to analyse when you get a panic or
> when you dump the memory.
>
> Regards,
>   Vincent

FWIW, I picked 0x137 through 0x139 because they all land within the first
page of memory, which should be guaranteed to fault.  I believe that
0xdeadbeef might be a valid address on large memory systems, thereby not
causing the immediate failure I wanted.  If anyone can think of symbolic
values < 4096, I'm open to using them.

Mike "Silby" Silbersack


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