linux-kernel - Re: Wonkiness with keyboard adapter - not sure if it's in USB or input systems

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]

Message-ID: <Pine.LNX.4.44L0.1104271316370.2239-100000@iolanthe.rowland.org>
Date:	Wed, 27 Apr 2011 13:23:31 -0400 (EDT)
From:	Alan Stern <stern@...land.harvard.edu>
To:	Jiri Kosina <jkosina@...e.cz>
cc:	Valdis.Kletnieks@...edu, Greg Kroah-Hartman <gregkh@...e.de>,
	Dmitry Torokhov <dmitry.torokhov@...il.com>,
	<linux-kernel@...r.kernel.org>, <linux-usb@...r.kernel.org>,
	<linux-input@...r.kernel.org>
Subject: Re: Wonkiness with keyboard adapter - not sure if it's in USB or
 input systems

On Tue, 26 Apr 2011, Jiri Kosina wrote:

> It seems like the BIOS handover of the USB input device doesn't work 
> properly.
> 
> The way things usually work in such situations -- BIOS is able to 
> understand USB input devices in a very basic mode (hidp) and translate the 
> events into PS/2-looking events, so that things like grub (which don't 
> understand USB HID) are able to see keyboard events -- BIOS presents those 
> as PS/2 devices.
> 
> Once kernel is booted, it takes over devices in this 'legacy' mode from 
> BIOS, and initializes them properly as USB input devices.
> 
> Seems like this process is broken on your system. Could you please try to 
> disable legacy USB emulation in your BIOS, and see if the problem 
> persists? (it will make USB keyboard unavailable in grub).

If the drivers are set up properly in the initrd image, this shouldn't 
be a problem.  Still, it's worth testing.  A good test would be to use 
two keyboards, one attached to the PS2 port for typing in the 
decryption key and one attached to the adapter.  Does the second 
keyboard work after the kernel has finished starting up?

If it doesn't, does "rmmod ehci ; modprobe ehci" make any difference?  

Also, once the kernel is running, it is possible to fire up usbmon and
see what it reveals.

Alan Stern

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/