[syslinux] Avoid returning to menu if boot error happened

[Anatol Pomozov]

Hi

On Thu, Jul 10, 2014 at 11:04 PM, Ady <ady-sf at hotmail.com> wrote:
>
>> Hi
>>
>> I have a weird early boot bug that most likely happens because of
>> interaction between syslinux (6.03pre18), btrfs and initram generated
>> by Linux Arch installer.
>>
>> For some reason boot fails. Syslinux prints some information and
>> returns back to the menu. Unfortunately it clears all the messages
>> from screen. I really want to know what boot process prints there.
>>
>> Looking at  com32/elflink/ldlinux/execute.c (I believe it is where the
>> error handled) I see the comment: /* If this returns, something went
>> bad; return to menu */
>>
>> Would it be better avoid returning to menu in case of an error? I
>> think syslinux should print message "Press any key to return back to
>> menu". This will preserve the error messages needed during debugging.
>> What do you think?
>
> You don't _have_ to use a menu to boot, and the default behavior is
> (or should be) not to clear the screen, so probably you can edit your
> syslinux.cfg so to obtain (and be able to read) the error message
> (that is, if indeed the error message is generated by Syslinux).
>
> For instance:
>  _ avoid the UI directive,
>  _ avoid ONTIMEOUT,
>  _ avoid ONERROR,
>  _ avoid MENU CLEAR
>  _ use a higher TIMEOUT,
>  _ use PROMPT 1,
>  _ use DEFAULT <problematic_label>.
>
> These are just basic changes that _might_ help. In some cases, some
> of the above should not be applied, and sometimes other changes are
> needed.

Thanks, it works! For some reason I thought UI option is required and
the text menu is the default one. After I removed the UI I am able to
see the boot error message.

Though I still think that it makes more sense to do pause on a boot error.

> The main point is that a basic syslinux.cfg (or equivalent) should
> help you see the error messages.
>
> If you need more details, please post your Syslinux configuration
> file.

I was using config file template from my distro
https://projects.archlinux.org/svntogit/packages.git/tree/trunk/syslinux.cfg?h=packages/syslinux