Subject: Re: [bug#30604] [PATCH v8 3/7] linux-boot: Load kernel modules only when the hardware is present.

From: Danny Milosavljevic <[email-masked]>
Date: Fri, 9 Mar 2018 23:44:34 +0100

Hi Ludo,

sorry for the many e-mails - I'm recollecting all the workarounds :)

>--8<---------------cut here---------------start------------->8---
>loading '/gnu/store/n2zvdxp25kvg7wy5xr1y5n9r4502fw80-linux-vm-loader'...
>environment variable `PATH' set to `/gnu/store/vxl918zb9brnrgaipzsykpy3mzcafvcr-qemu-minimal-2.11.1/bin:/gnu/store/lvkaf3xlvy57bvap51xlzb209ilbkgcv-parted-3.2/sbin:/>gnu/store/nm305rpb2mvridkyj4l3636nc9ql4lf9-e2fsprogs-1.43.6/bin:/gnu/store/nm305rpb2mvridkyj4l3636nc9ql4lf9-e2fsprogs-1.43.6/sbin:/gnu/>store/0sq2nflm42x0znkv44add0gk82khkcb6-dosfstools-4.1/sbin:/gnu/store/0hl513mnpkhszm2hjai2w9cxmpxs0vgq-sed-4.4/bin:/gnu/store/1h44pkgdd7n6s3i2vjh54awsvfmc219j->grep-3.1/bin:/gnu/store/kgzvfby2ggi1xawsh5vjh4s93qk2dp9k-coreutils-8.28/bin:/gnu/store/k7r2m2wgj8x8jjhccwjsiimp0dlzxb7i-findutils-4.6.0/bin:/gnu/store/>ahxc89r6npzf2bbl8yg5vdjicskzzjf3-gawk-4.1.4/bin'
>creating partition table with 2 partitions (20.0 MiB, 40.0 MiB)...
>Warning: The resulting partition is not properly aligned for best performance.
>creating ext4 partition...
...
[    3.235493] FAT-fs (vda2): IO charset iso8859-1 not found
ERROR: In procedure mount:
In procedure mount: Invalid argument
--8<---------------cut here---------------end--------------->8---

>Here the nls_iso8859-1 module doesn’t get loaded and modprobe isn’t even
>invoked, although my understanding is that it should (per ‘load_nls’ in
>nls_base.c in the kernel, called from vfat/inode.c).

Yeah, that was an evil problem.  There are two different ways linux-boot
can boot:
* Either it loads a full system in which case /run/booted-system will
contain kernel module files which can and will be loaded
* Or it loads a "--load" file only - in which case there's no system
modprobe, but switch-root just switched our pure-Guile modprobe away,
so now we are out of modprobes :)