Re: [PATCH] ibmphp: Fix module ref count underflow

From: Greg KH
Date: Wed Dec 10 2008 - 17:34:50 EST


On Wed, Dec 10, 2008 at 02:43:34PM -0500, Neil Horman wrote:
> Hey-
> I happened to notice that the ibmphp hotplug driver does something
> rather silly in its init routine. It purposely calls module_put so as to
> underflow its module ref count to avoid being removed from the kernel. This is
> bad practice, and wrong, since it provides a window for subsequent module_gets
> to reset the refcount to zero, allowing an unload to race in and cause all sorts
> of mysterious panics. If the module is unsafe to load, it should inform the
> kernel as such with a call to __unsafe. The patch below does that.
>
> Regards
> Neil
>
> Signed-off-by: Neil Horman <nhorman@xxxxxxxxxxxxx>

Jesse is the PCI maintainer now, you should send this to him to verify
that it goes in.

Feel free to add my:
Acked-by: Greg Kroah-Hartman <gregkh@xxxxxxx>

to this, nice job.

thanks,

greg k-h
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