at_keyboard breaks rebooting of system

at_keyboard breaks rebooting of system

[Olaf Hering]

While trying to enable a german keymap in grub2 I run into some grub2 or
BIOS bug on my Esprimo M9400. After 'terminal_input at_keyboard' reboot
just hangs, in grub2, Linux and Xen. Poweroff still works. In Linux the
cursor stops blinking when the reboot is supposed to happen. In grub2
the cursor does still blink.

It looks like at_keyboard is required to get a non-US keymap in grub2.

Any idea what might be the culprit, anything I can try?

Olaf

Re: at_keyboard breaks rebooting of system

[Andrei Borzenkov]

On Thu, Mar 24, 2016 at 1:20 PM, Olaf Hering <olaf@aepfle.de> wrote:
> While trying to enable a german keymap in grub2 I run into some grub2 or
> BIOS bug on my Esprimo M9400. After 'terminal_input at_keyboard' reboot
> just hangs, in grub2, Linux and Xen. Poweroff still works. In Linux the
> cursor stops blinking when the reboot is supposed to happen. In grub2
> the cursor does still blink.
>
> It looks like at_keyboard is required to get a non-US keymap in grub2.
>
> Any idea what might be the culprit, anything I can try?
>

One potential problem is that at_keyboard directly competes with BIOS
for input characters. It probably should disable BIOS keyboard
processing on i386-pc platform while is is active.

There was alternative suggestion (because at_keyboard was too
unreliable) to use extended BIOS keyboard service.

https://lists.gnu.org/archive/html/help-grub/2015-07/msg00004.html
(and thread that led to it)

... hmm ... I thought there was a followup but I cannot find it.

Re: at_keyboard breaks rebooting of system

[Vladimir 'phcoder' Serbinenko]

[-- Attachment #1: Type: text/plain, Size: 1403 bytes --]

Le jeu. 24 mars 2016 12:10, Andrei Borzenkov <arvidjaar@gmail.com> a écrit :

> On Thu, Mar 24, 2016 at 1:20 PM, Olaf Hering <olaf@aepfle.de> wrote:
> > While trying to enable a german keymap in grub2 I run into some grub2 or
> > BIOS bug on my Esprimo M9400. After 'terminal_input at_keyboard' reboot
> > just hangs, in grub2, Linux and Xen. Poweroff still works. In Linux the
> > cursor stops blinking when the reboot is supposed to happen. In grub2
> > the cursor does still blink.
> >
> > It looks like at_keyboard is required to get a non-US keymap in grub2.
> >
> > Any idea what might be the culprit, anything I can try?
> >
>
> One potential problem is that at_keyboard directly competes with BIOS
> for input characters. It probably should disable BIOS keyboard
> processing on i386-pc platform while is is active.
>
> There was alternative suggestion (because at_keyboard was too
> unreliable) to use extended BIOS keyboard service.
>
Which doesn't provide enough data to handle some of common keyboard layout
features like AltGr

>
> https://lists.gnu.org/archive/html/help-grub/2015-07/msg00004.html
> (and thread that led to it)
>
> ... hmm ... I thought there was a followup but I cannot find it.
>
>
> _______________________________________________
> Grub-devel mailing list
> Grub-devel@gnu.org
> https://lists.gnu.org/mailman/listinfo/grub-devel
>

[-- Attachment #2: Type: text/html, Size: 2203 bytes --]