Re: grub-mkimage

[Pascal]

hi,

for the second point of the verbose mode, the qemu allows me to get the
messages delivered by grub :-)

regards

Le mar. 1 mars 2022 à 09:29, Pascal <patatetom@gmail.com> a écrit :

> hi (and sorry for this long time),
>
> thank you for the explanations about the graft point syntax which should
> probably be present in the grub-mkstandalone documentation.
> so, you should replace SOURCE by GRAFTPOINT in the general presentation
> (usage line).
>
> I was mentioning prefix because three small dots are present after the
> SOURCE argument in the usage line and I thought it was possible to
> provide other arguments and therefore perhaps prefix.
>
> thank you for the proposal but unfortunately I don't think I have the
> knowledge to send patches, even for documentation.
>
> the verbose mode (thanks again),
> 1) the verbose mode is only activated when the set debug=all line is
> played : is it possible to activate it as soon as grub is loaded/launched
> (at UEFI level may be) ?
> 2) a lot of messages are displayed on the screen and the menu ends up
> taking over : is it possible to capture these messages (with redirection to
> a file may be) ?
>
> regards, lacsaP.
>
> Le jeu. 10 févr. 2022 à 04:34, Glenn Washburn <development@efficientek.com>
> a écrit :
>
>> On Wed, 26 Jan 2022 10:34:28 +0100
>> Pascal <patatetom@gmail.com> wrote:
>>
>> > hi,
>> >
>> > thank you Andrei for taking the time to read and answer me.
>> >
>> > I try to reduce the space taken by GRUB as much as possible.
>> > this way, I only have the bootloader and a basic configuration file :
>> >
>> > # ll -h /run/live/bootmnt/efi/boot/bootx64.efi
>> > -rwxr-xr-x 1 root root 584K 26 janv. 07:46
>> > /run/live/bootmnt/efi/boot/bootx64.efi
>> >
>> > # cat /run/live/bootmnt/efi/menu.cfg
>> > menuentry MyLiveSystem {
>> > linux /boot/kernel ...
>> > initrd /boot/initramfs
>> > }
>> >
>> > I tried to remove efi_gop and efi_uga but I always get (at least with
>> Qemu)
>> > the following error message :
>> >
>> > error: no suitable video mode found.
>> > Booting in blind mode
>> >
>> > adding video and/or video_fb modules (which are required/used by efi_*
>> > modules) does not change anything.
>> >
>> > I tried to use grub-mkstandalone but I fail to generate a bootloader
>> that
>> > works as simply as my tiny one.
>> > here is the command used :
>> >
>> > grub-mkstandalone \
>> >    --disable-shim-lock \
>> >    --fonts="" --locales="" --themes="" \
>> >    --modules="linux normal minicmd gzio efi_uga efi_gop fat part_gpt
>> chain"
>> > \
>> >    -o /run/live/bootmnt/efi/boot/test.efi \
>> >    -O x86_64-efi \
>> >    "boot/grub/grub.cfg=/run/live/bootmnt/efi/menu.cfg"
>> >
>> > as root and prefix use (memdisk), I get the following error message :
>> >
>> > error: file `/boot/kernel' not found.
>> >
>> > only the cmdpath variable refers to my disk with (hd0,gpt2)/efi/boot.
>> > it works once the root variable is manually set to (hd0,gpt2) (but not
>> with
>> > (,gpt2)).
>> >
>> > as you are involved in the development of GRUB, I have a small remark
>> about
>> > grub-mkstandalone : the SOURCE parameter is not discussed in its man
>> page
>> > apart from the general presentation (eg. invocation).
>> > I found my last parameter ("boot/grub/grub.cfg=...") on the internet :
>> what
>> > more information/option can be passed ? prefix may be ?
>>
>> If you run "grub-mkstandalone --help", you'll see a line at the bottom
>> saying "Graft point syntax (E.g. /boot/grub/grub.cfg=./grub.cfg) is
>> accepted". This could proabably be worded better and perhaps more
>> detailed. However, "graft-point" syntax is FROM=TO where FROM is a path
>> valid in the host (the one running grub-mkstandalone) and TO is what
>> the files path should be in the memdisk. If the source argument has no
>> equal sign, then it treated as SOURCE=SOURCE. As fas as I can tell
>> that's all that SOURCE is, a list of such arguments.
>>
>> What kind of prefix are you looking for?
>>
>> It would be great if you had any ideas on how to make the documentation
>> more clear or better in some way. If you have some explicit feedback,
>> please let me/us know. And even better, documentation patches welcome!
>>
>> >
>> > a last question (for today ;-)) to which I did not find an answer : is
>> it
>> > possible to switch the bootloader to verbose mode ?
>>
>> If you set the debug variable to "all" (eg. "set debug=all"), then you
>> turn on all debugging messages. This may be what you're looking for.
>>
>> Glenn
>>
>