netdev - Re: calling request_firmware() from module init will not work with recent/future udev versions

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Sat, 14 Jan 2012 12:45:32 -0600
From:	Larry Finger <Larry.Finger@...inger.net>
To:	Kay Sievers <kay.sievers@...y.org>
CC:	netdev@...r.kernel.org, linux-wireless@...r.kernel.org,
	Tom Gundersen <teg@...m.no>, Andy Whitcroft <apw@...onical.com>
Subject: Re: calling request_firmware() from module init will not work with
 recent/future udev versions

On 01/14/2012 09:25 AM, Kay Sievers wrote:
> Hey,
>
> just a heads-up, when bug reports are coming in now. The kernel log
> might look like a kernel failure, but it's caused by recent userspace
> changes.
>
> We changed udev to strictly enforce sequence order and dependency
> handling of events. This seems to break some netdev drivers which
> block in modprobe until the firmware from userspace is loaded into the
> driver.
>
> I think it's out of question, that nothing must block in module init
> and rely on a userspace transaction to be fulfilled to finish the
> init_module() syscall. If userspace is not running properly, nothing
> will work. Built-in drivers and the transition from initramfs to the
> real root can't be handled properly that way.
>
> These drivers need to be fixed to load their firmware during ifup,
> which would be the most flexible solution. That way, it should also
> work if the driver is built-in, or is loaded from initramfs and no
> firmware is available.
> Alternatively, the firmware request should be able to use the aync
> firmware_request API and not the blocking one.
>
> We might need to work around that in the current udev for now, but
> these drivers will definitely break in future udev versions.
> Userspace, these days, should not be in charge of papering over
> obvious kernel bugs like this.
>
> These are the drivers we received bug reports so far. We didn't look
> into any of details of the drivers, but according to the logs, they
> seem to block for 60 seconds in modprobe, when userspace is not
> behaving like expected:
>    bnx2/bnx2-mips-06-6.2.1.fw
>    rtlwifi/rtl8192sefw.bin
>    brcm/bcm43xx-0.fw

Thanks for the heads-up. Do you have a reference for the problem with 
rtlwifi/rtl8192sefw.bin? Google did not find anything that looked appropriate.

Thanks,

Larry

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html