Sergey Bugaev writes: Hello Sergey,
> On Wed, May 17, 2023 at 9:25 PM Janneke Nieuwenhuizen <jann...@gnu.org> wrote:
> I've recently been doing this kind of debugging early boot-up process
> *a lot*, so maybe I could provide some tips indeed. For getting more
> lines of output, try console=com0 on gnumach cmdline, and run qemu
> with -nographic -serial stdio or something like that.
Now that was really a great help, thanks! It helped me (e)diff many
different qemu runs: plain debian, debian+guix/pci-arbiter,
debian+guix/pci-arbiter+guix/rumpdisk, plain guix,
guix+debian/pci-arbiter, guix+debian/pci-arbiter+debian/rumpdisk...
It was immediately obvious that the messages from rumpdisk were (nearly)
identical. As the boot went silent at the end I assumed a crash or a
hang in rumpdisk. After inspecting the diffs and seeing nothing really
different, I noticed that I used -m 4096 for debian and -m 1024 for guix
on the qemu command line. Do'h, turns out rumpdisk needs at least
1200MB...
With
https://gitlab.com/janneke/guix/-/tree/wip-hurd
I've now succesfully been doing
--8<---------------cut here---------------start------------->8---
./pre-inst-env guix system image -t hurd-raw gnu/system/examples/bare-hurd.tmpl
cp /gnu/store/r5dpblnfsj08jh3hdmn8s6l9xaczwn65-disk-image guix.img
sudo losetup -o $((512*2048)) /dev/loop0 guix.img
sudo mount /dev/loop0 /mnt
edit /mnt/boot/grub/grub.cfg, adding console=com0
sudo umount /mnt
--8<---------------cut here---------------end--------------->8---
and then
--8<---------------cut here---------------start------------->8---
guix shell qemu -- qemu-system-i386 \
-m 4096 \
--enable-kvm \
--device rtl8139,netdev=net0 \
--netdev user,id=net0,hostfwd=tcp:0.0.0.0:11022-:2222 \
--snapshot \
--no-reboot \
--device virtio-serial-pci \
--nographic \
--serial mon:stdio \
--hda r5dpblnfsj08jh3hdmn8s6l9xaczwn65-disk-image+CONSOLE=COM0
--8<---------------cut here---------------end--------------->8---
Just for fun, find the succesful log attached.
Is there a way to pass the "console=com0" argument from the QEMU command
line? That would be nice!
> Other than that, just attach gdb and see what it crashes on? Like this:
>
> $ gdb /path/to/gnumach
> (gdb) tar rem :1234
> (gdb) b i386_exception
> (gdb) b task_terminate
> (gdb) b Panic
> (gdb) add-symbol-file /path/to/rumpdisk.static
> blah-blah (y/n?) y
> (gdb) c
[..]
Ah, I had no idea; this is so helpful. Maybe a good idea to have this
on the website/wiki, right?
Greetings,
Janneke
guix-glibc.log
Description: Binary data
-- Janneke Nieuwenhuizen <jann...@gnu.org> | GNU LilyPond https://LilyPond.org Freelance IT https://www.JoyOfSource.com | Avatar® https://AvatarAcademy.com
