[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Menu time-out missing when GRUB is loaded quickly and `at_keyboard`

From: Paul Menzel
Subject: Menu time-out missing when GRUB is loaded quickly and `at_keyboard`
Date: Mon, 14 Jan 2019 14:08:29 +0100
User-agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.4.0

Dear GRUB folks,

When the module `at_keyboard` is directly into the GRUB image (`--modules`), and GRUB is loaded really quickly, then the timer, which, after counting down to 0 (`GRUB_TIMEOUT`), starts the selected entry, is not shown.

I noticed this issue on the ASRock E350M1 with coreboot and a small GRUB payload, and a PS/2 keyboard connected. Due to the missing time-out, I manually have to confirm the selected entry. By chance, the keyboard wasn’t connected setting up the system somewhere else, and that made it work as expected. So, it looks like, it’s related to `at_keyboard`, and some race, because the bigger default GRUB payload also does not show the problem.

Luckily, it’s easily reproducible with GRUB’s standard `default_payload.elf` and QEMU.

Please find the instructions below to reproduce the issue.

    $ git clone
    $ cd coreboot
    $ # save attached grub.cfg in the directory
    $ util/scripts/config -e PAYLOAD_GRUB2
    grep: .config: Datei oder Verzeichnis nicht gefunden
    $ util/scripts/config -e GRUB2_INCLUDE_RUNTIME_CONFIG_FILE
    $ util/scripts/config -e GRUB2_MASTER
$ util/scripts/config -e CONFIG_COREBOOT_ROMSIZE_KB_2048 # default of 512 KB too small for GRUB payload
    $ util/scripts/config -e ANY_TOOLCHAIN
    $ # or: make crossgcc-i386 CPUS=`nproc`
    $ make olddefconfig
    $ make -j`nproc`
    $ qemu-system-x86_64 --version
     QEMU emulator version 3.1.0 (Debian 1:3.1+dfsg-2+b1)
Copyright (c) 2003-2018 Fabrice Bellard and the QEMU Project developers
    $ qemu-system-x86_64 -M pc -bios build/coreboot.rom -serial stdio

*No* time-out is shown. Telling QEMU to emulate a USB keyboard, indirectly disabling the PS/2 keyboard, the time-out *is* shown.

    $ qemu-system-x86_64 -M pc -bios build/coreboot.rom -serial stdio \
    -usb -device usb-kbd

Not including `at_keyboard` directly in GRUB’s “core image”, modules loaded automatically, the time-out is also shown.

`set debug=at_keyb` did not show anything interesting.

Can you reproduce that, and see what the problem is?

Kind regards,


PS: Please find the instructions to build GRUB as a coreboot payload done by coreboot’s Kconfig system automatically, and how put it into the coreboot filesystem CBFS.

$ git clone
$ cd grub
$ git describe --tags --dirty
$ ./
$ ./configure --with-platform=coreboot
$ make default_payload.elf # this includes `at_keyboard`
$ cp default_payload.elf my/coreboot/folder/
$ cd my/coreboot/folder/
$ build/cbfstool build/coreboot.rom print
$ build/cbfstool build/coreboot.rom remove -n fallback/payload
$ build/cbfstool build/coreboot.rom add-payload -f payload.elf -n fallback/payload -c lzma

Kind regards,


Attachment: grub.cfg
Description: Text document

reply via email to

[Prev in Thread] Current Thread [Next in Thread]