Message-ID: <1343139390.4415.31.camel@jlt3.sipsolutions.net> (sfid-20120724_161642_535858_48845418)
Subject: Re: calling request_firmware() from module init will not work with
 recent/future udev versions
From: Johannes Berg <johannes@sipsolutions.net>
To: Kay Sievers <kay@vrfy.org>
Cc: netdev@vger.kernel.org, linux-wireless@vger.kernel.org,
	Tom Gundersen <teg@jklm.no>, Andy Whitcroft <apw@canonical.com>
Date: Tue, 24 Jul 2012 16:16:30 +0200
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On Thu, 2012-07-19 at 12:46 +0200, Kay Sievers wrote:

> >> > What I'm was asking then is this: Can udev know that it is running from
> >> > initramfs (presumably that can't be too hard) and simply not reply to
> >> > async requests it doesn't have firmware for? Then once the real root is
> >> > mounted it could satisfy (or not) firmware requests from the real root.
> >>
> >> We can surely change it to not cancel the firmware request.
> >>
> >> Either by making it aware that we run from initramfs, or by never
> >> cancelling any firmware request and just leave it hanging around for
> >> forever?
> 
> Never say 6 months is a long time to reply. :)

Hehe :-)

> Fedora uses systemd in the initramfs now, which made it trivial to
> implement this, and to leave the firmware requests hanging around
> until we reach in the real rootfs and know if the firmware file is
> available:
>   http://cgit.freedesktop.org/systemd/systemd/commit/?id=39177382a4f92a834b568d6ae5d750eb2a5a86f9
> 
> The logic to tell udev that it runs in the initramfs could easily be
> implemented by other initramfs tools than dracut, but they usually do
> not really follow what we do here, so this might for now only work on
> recent systems using dracut.

Ok, too bad there wasn't a generic way, but at least there's a way
now :-)

Anyway, I think this is a good thing.

johannes