Re: Grub2 UEFI boot and serial console output

[Andrei Borzenkov]

On Mon, Jan 16, 2017 at 11:36 AM, Matwey V. Kornilov
<address@hidden> wrote:
>>
>> I think here is my issue:
>>
>> terminal_input says that 'console' is active terminal and no other
>> terminals available.
>>
>> serial --speed=115200 efi0 says "can't find command `serial'"
>>
>
> Ok, now I see! There is file /boot/grub2/x86_64-efi/serial.mod but
> isnmod serial says that there is no such file.
>

Well

1. $prefix must be set correctly (normally is done for you by
grub-install & Co.; I do not know how you created your image)
2. Device which is part of $prefix must of course exist. You may need
to explicitly load partition driver (not autoloaded) and/or virtual
storage drivers (Linux MD, LVM2, LUKS, etc)
3. You need filesystem driver for this device (normally autoloaded).
4. Most vendors build images for use with Secure Boot that disable
module load. Unless module is included in the image by vendor, it is
flat unavailable. If you are using such image (you most likely do if
you enabled secure boot support in your OS configuration) - check how
image is built. You are using openSUSE, are not you?

All of this is basic stuff and has nothing to do with your problem
with serial port.