Re: [PATCH 1/3] firmware: Avoid superfluous usermodehelper lock

From: Ming Lei
Date: Wed May 08 2013 - 11:52:13 EST


On Wed, May 8, 2013 at 2:56 PM, Takashi Iwai <tiwai@xxxxxxx> wrote:
> When a firmware file can be loaded directly, there is no good reason
> to lock usermodehelper. It's needed only when the direct fw load
> fails and falls back to the user-mode helper.

I remembered that we discussed the problem before, :-)

Some crazy drivers might call request_firmware inside resume callback
(for example, USB devices might be rebind in resume), with
usermodehelper_read_lock, we can find the mistake easily and log it.

I am wondering if it is good to remove the usermodehelper lock.

Could you let us know any benefit to do it?

Thanks,
--
Ming Lei
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