Re: 2.6.9+ keyboard LED problem

From: Ville Hallik
Date: Thu Jan 06 2005 - 09:53:19 EST


In article <200501060143.13428.dtor_core@xxxxxxxxxxxxx> you wrote:

> Actually it is ACK processing hardening that is very useful at setup stage
> but is getting in our way once keyboard is initialized and commands are
> intermixed with good data.

> Could you please try the patch below? It is just a quick hack, just to prove
> the idea. If it works for you I will prepare the proper fix later.

> --
> Dmitry

> ===== drivers/input/serio/libps2.c 1.2 vs edited =====
> --- 1.2/drivers/input/serio/libps2.c 2004-10-20 03:13:08 -05:00
> +++ edited/drivers/input/serio/libps2.c 2005-01-06 01:20:11 -05:00
> @@ -250,7 +250,7 @@
> }
> /* Fall through */
> default:
> - return 1;
> + return 0;
> }
>
> if (!ps2dev->nak && ps2dev->cmdcnt)

This quick hack works for me too. Thanks!

However, it is still easy to make PS/2 keyboard and mouse completely
unusable with the following "sleepless" shell script (but it probably does
not qualify as DoS because access to PS/2 keyboard is limited to local user
only):

while : ; do xset led 3 ; xset -led 3 ; done

Even after killing this over network login, both keyboard and mouse are
still unresponsive for about 10..20 seconds. It was not that fatal with 2.6.8.

--

Ville Hallik
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