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Message-ID: <4cc25cb20801230634w2cab51c7w8d62d75ec982f132@mail.gmail.com>
Date: Wed, 23 Jan 2008 22:34:57 +0800
From: rmingming <mingming.nk@gmail.com>
To: linux-kernel@vger.kernel.org
Subject: Re: Is try_module_get buggy?
In-Reply-To: <200801171409.39389.rusty@rustcorp.com.au>
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	 <200801171409.39389.rusty@rustcorp.com.au>
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> Hi rminming,
>
> try_module_get is designed to ensure that you don't call a function inside a
> module without a reference.  Like any reference function, it cannot handle
> the case where the argument is invalid (or invalidated partway through the
> call).
>
> In this case, the module pointer is usually inside a registered structure.
> The pointer will be valid until the structure is unregistered, which the
> calling code presumably prevents while it's doing a lookup.
>
> Hope that clarifies,
> Rusty.
>

Hi Rusty,

Thank you so much!
I think you mean that this situation can really happen, because this
is a reference function, but it is so seldom, and the common result of
this situation is a kernel oops, it's not very important. Am I right?

Sorry about later reply, thanks again.
Best wishes,

rmingming