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From: John Baldwin <jhb@freebsd.org>
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	(bigwig.baldwin.cx); Mon, 01 Aug 2011 09:59:39 -0400 (EDT)
Cc: Andrew Thompson <andy@fud.org.nz>
Subject: Re: variable init
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On Monday, August 01, 2011 3:09:27 am Andrew Thompson wrote:
> Hi,
> 
> Looking at,
> 
> http://www.freebsd.org/cgi/query-pr.cgi?pr=159345
> 
> The lock is a global variable, declared as
> 
> static struct mtx       lagg_list_mtx;
> 
> I would expect this to be zeroed memory, is this guaranteed?

Yes, but when if_lagg.ko is loaded, the runtime linker resolves references to 
'lagg_list_mtx' to point to the lock that is in the kernel's .bss from the 
compiled-in lagg, not the one in the .ko file.  However, both initializer 
functions run (the one from the kernel and the one from the .ko) which causes 
the panic.

-- 
John Baldwin