[Buildroot] Boot process stuck at "GRUB loading.." since 2021.02.1

[Peter Seiderer]

Hello Walter,

On Thu, 7 Oct 2021 20:36:07 +0000, "Walter, Stefan" <stefan.walter at iml.fraunhofer.de> wrote:

> Hi,
>
> the following used to work until Buildroot 2021.02, i.e. the resulting image booted normally. Ever since Buildroot 2021.02.1 and up until 2021.02.5, the resulting image does not boot any more - the boot process either gets stuck right after displaying "GRUB loading..", or it reboots at that point, leading to an infinite boot loop.
>
> What I'm doing:
>
> 1. Run Buildroot to create a root partition image (my_defconfig attached).
> 2. Create a GRUB image like this (grub_early.cfg attached):
>
> /path/to/buildroot-sdk/host/bin/grub-mkimage --config=grub_early.cfg --directory=/path/to/buildroot-sdk/host/lib/grub/i386-pc -o ./genimage_input_tmp/grub_core.img --format=i386-pc --prefix==/boot/grub biosdisk part_msdos ext2 normal linux configfile
>
> 3. Create a home partition image like this:
>
> MKE2FS_CONFIG=/path/to/buildroot-sdk/host/etc/mke2fs.conf /path/to/buildroot-sdk/host/sbin/mke2fs -d home_partition_prep/home -j -L home -t ext3 -U random -b 4096 ./genimage_input_tmp/home.ext3 25M
>
> 4. Create a disk image like this (genimage.cfg attached):
>
> /path/to/buildroot-sdk/host/bin/genimage --loglevel=1 --config=genimage.cfg --inputpath=./genimage_input_tmp --outputpath=images --rootpath=home_partition_prep --tmppath=./genimage_tmp --tune2fs=/path/to/buildroot-sdk/host/usr/sbin/tune2fs --e2fsck=/path/to/buildroot-sdk/host/usr/sbin/e2fsck
>
> Does anyone have any idea what's going wrong here since 2021.02.1?

Only known issue was 'Bug 13586 - grub failure with BR2_OPTIMIZE_3' (see [1]),
but should be fixed by commit 'boot/grub2: workaround breakage with -O2,
-O3 build' (see [2])

Regards,
Peter

[1] https://bugs.busybox.net/show_bug.cgi?id=13586
[2] https://git.buildroot.net/buildroot/commit/?id=7cb51d4843caaa9144270d92f86e60d8b5a2a1ec

>
> Best regards,
> Stefan