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Date: Sun, 27 Jan 2013 09:41:28 -0500
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Subject: Re: dtrace vs module unloading
From: Ryan Stone <rysto32@gmail.com>
To: Andriy Gapon <avg@freebsd.org>
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On Sun, Jan 27, 2013 at 7:24 AM, Andriy Gapon <avg@freebsd.org> wrote:

>
> It seems that FreeBSD DTrace currently does not track module loading /
> unloading
> at all.  dtrace_module_loaded/dtrace_module_unloaded are both under ifdef
> sun.
>
> I think that this is a root cause of e.g. fbt probes for some functions
> remaining after a module that provides the functions is unloaded.
>
> It looks like currently we do not post any event when a module gets loaded
> /
> unloaded.  Perhaps this is one of the factors in current situation.
> OTOH, in Solaris they just have some dtrace hooks in the form of function
> pointers directly in the module handling code (equivalent of our
> kern_linker).
>

I have a PR in about this.  I haven't had a chance to look into fixing it
myself.