From: Borislav Petkov
> Sent: 02 April 2019 11:02
>
> On Mon, Apr 01, 2019 at 07:53:46PM +0200, Jann Horn wrote:
> > Hm. request_microcode_fw() gets that buffer from
> > request_firmware_direct(), which does this:
> >
> > __module_get(THIS_MODULE);
> > ret = _request_firmware(firmware_p, name, device, NULL, 0,
> > FW_OPT_UEVENT | FW_OPT_NO_WARN |
> > FW_OPT_NOFALLBACK);
> > module_put(THIS_MODULE);
> > return ret;
> >
> > What is that module_get()/module_put() supposed to be good for? Are we
> > expecting that caller to do something ridiculous like calling
> > module_put() on us? This doesn't seem to make any sense.
>
> Yah, the microcode thing used to be a module. Not anymore.
That probably makes diddly-squit difference.
There has to be a 'hold' on THIS_MODULE in order to be executing
code from it.
You only (usually) need an extra reference for a kernel thread,
and that needs to exit with module_put_and_exit().
David
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