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

On Wed, Dec 10, 2008 at 02:28:12PM -0800, Greg KH wrote:
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! I've forwarded the patch on to Jesse.

Best
Neil

thanks,

greg k-h
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