Date: Thu, 26 Jun 2014 18:18:05 +0200
Message-ID: <s5hmwczve4i.wl%tiwai@suse.de>
From: Takashi Iwai <tiwai@suse.de>
To: "Luis R. Rodriguez" <mcgrof@do-not-panic.com>
Cc: chunkeey@googlemail.com, leedom@chelsio.com, cocci@systeme.lip6.fr,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        gregkh@linuxfoundation.org, "Luis R. Rodriguez" <mcgrof@suse.com>
Subject: Re: [PATCH 0/3] drivers: expand usage of request_firmware_direct()
In-Reply-To: <1403649583-12707-1-git-send-email-mcgrof@do-not-panic.com>
References: <1403649583-12707-1-git-send-email-mcgrof@do-not-panic.com>
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At Tue, 24 Jun 2014 15:39:40 -0700,
Luis R. Rodriguez wrote:
> 
> From: "Luis R. Rodriguez" <mcgrof@suse.com>
> 
> Takashi added request_firmware_direct() via bba3a87e9 through v3.14-rc1
> which avoids the unnecessary delay introduced by using the udev firmware
> loader in case the first try failed when loading we know loading "firmware"
> is optional. The first use case was for microcode update but if drivers are
> using it for optional configuration updates, custom EEPROMs, and other
> junk other than firmware that should apply as well as good use cases,
> specially if the driver already had a first phase in which it loaded
> the first required firmware. While reviewing one driver I figured it'd
> be best to try to give formalizing a check with SmPL. This isn't perfect
> it had 1 false possitive drivers/fmc/fmc-fakedev.c on the entire kernel
> run but my hope is this can be extended a bit more to build more
> confidence, and then perhaps stuff it as a coccicheck.
> 
> I suppose this will not be required once and if we remove
> CONFIG_FW_LOADER_USER_HELPER. Is that ever going away for good? I know
> there was a recent attempt to remove the udev loader support but
> it was unclear if the special alternative helper support would be
> removed upstream from the kernel.

Actually a few weeks ago I sent a patch to make request_firmware()
with usermode helper explicitly to be used by some drivers (like
dell-rbu).  I hope Greg took it for 3.17.  Once when this patch is in,
distros can turn off the usermode helper fallback gracefully, so no
ugly timeout issue shouldn't happen.


Takashi
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