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Subject: Re: dtrace vs module unloading
From: George Neville-Neil <gnn@neville-neil.com>
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On Jan 27, 2013, at 07:24 , Andriy Gapon <avg@FreeBSD.org> wrote:

>=20
> 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.
>=20
> 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.
>=20
> 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).
>=20

Hrm, sounds like a bug more than anythign else.  I don't know enough yet =
to say how to solve
this but if you want to track this you're welcome to create a PR and =
assign it to me.

Best,
George