Hi,

You need to ask a bit more specific, which differences you see exactly.

Thanks for the quick reply and yes I should be more specific. So the issue is on building an aarch64 package on a custom obs server instance. The worker calls qemu as follows:

[ 0s] Using BUILD_ROOT=/obsworker/worker/root_2/.mount [ 0s] Using BUILD_ARCH=aarch64:aarch64_ilp32:armv8l [ 0s] Doing kvm build in /obsworker/worker/root_2/root [ 0s] ... [ 20s] booting kvm... [ 20s] ### VM INTERACTION START ### [ 20s] Using UART console [ 20s] /usr/bin/qemu-system-aarch64 -nodefaults -no-reboot -nographic -vga none -cpu host -enable-kvm -M virt,gic-version=host -object rng-random,filename=/dev/random,id=rng0 -device virtio-rng-device,rng=rng0 -runas qemu -net none -kernel /boot/Image -initrd /boot/initrd -append root=/dev/disk/by-id/virtio-0 rootfstype=ext3 rootflags=data=writeback,nobarrier,commit=150,noatime ext4.allow_unsupported=1 mitigations=off panic=1 quiet no-kvmclock elevator=noop nmi_watchdog=0 rw rd.driver.pre=binfmt_misc console=ttyAMA0 init=/.build/build -m 8192 -drive file=/obsworker/worker/root_2/root,format=raw,if=none,id=disk,cache=unsafe -device virtio-blk-device,drive=disk,serial=0 -drive file=/obsworker/worker/root_2/swap,format=raw,if=none,id=swap,cache=unsafe -device virtio-blk-device,drive=swap,serial=1 -serial stdio -chardev socket,id=monitor,server,nowait,path=/obsworker/worker/root_2/root.qemu/monitor -mon chardev=monitor,mode=readline -smp 8

and fails after some time with...

[ 129s] [[0m[0;31m* [0m] A start job is running for dev-disk…virtio\x2d0.de

The device never appears

After debugging we found the reason in the different values for -initrd and -kernel. If take the above call and only replace -initrd and -kernel as follows:

-kernel /obsworker/worker/root_2/.mount/boot/kernel -initrd /obsworker/worker/root_2/.mount/boot/initrd

The build works and succeeds.

I'm pretty sure this is a configuration issue on this server but I have no clue were to look at.

Any help is much appreciated.

Thanks

Regards, Marcus

Hi,

It think you are missing "VMinstall: kernel-obs-build" in the prjconf.

Thanks, I tried that and it results in an unresolvable. It seems there is no kernel-obs-build for aarch64 available.

I wanted to understand the concept better and was reading more code. Please correct me when wrong. In the build package code there is:

/usr/lib/build/build-vm-kvm

and

---snip

armv8l|aarch64) kvm_bin="/usr/bin/qemu-system-aarch64" kvm_console=ttyAMA0 vm_kernel=/boot/Image vm_initrd=/boot/initrd test -e /boot/kernel.obs.guest && vm_kernel=/boot/kernel.obs.guest test -e /boot/initrd.obs.guest && vm_initrd=/boot/initrd.obs.guest

---snap

This is the issue we see. The worker does not provide /boot/kernel.obs.guest and /boot/initrd.obs.guest. The default settings for kernel and initrd applies but that doesn't work.

The suggested instruction:

VMinstall: kernel-obs-build

would install the package on the worker prior the build-vm-kvm code and this would lead to the use of obs.guest initrd/kernel files. Is that correct ?

Next I looked at one of my packages that builds successfully on build.opensuse.org. In the log I see:

[ 1s] unpacking preinstall image Ubuntu:debbuild/Ubuntu_20.04/preinstallimage-base [6fe2b94cfc6f3d08b3f38c628716bdc5] [ 4s] booting kvm... [ 4s] ### VM INTERACTION START ### [ 4s] Using UART console [ 4s] /usr/bin/qemu-system-aarch64 ... -kernel /boot/kernel.obs.guest -initrd /boot/initrd.obs.guest ...

There is no extra install of kernel-obs-build. Instead a preinstall image which probably provides the required data is used.

I see this behavior when building for Ubuntu using debbuild. Package builds for e.g Leap, Fedora on aarch64 seems to provide a kernel-obs-build package and contains:

[ 15s] [8/47] preinstalling kernel-obs-build...

In all of this situations the location for initrd and kernel is passed to kvm as

-kernel /var/cache/obs/worker/root_13/.mount/boot/kernel -initrd /var/cache/obs/worker/root_13/.mount/boot/initrd

Which was weird because I thought it would also be *.obs.guest

Can you advise what the preferred solution is to fix this OBS instance to allow package builds on the aarch64 workers ?

Sorry if the questions sounds dumb, I'm just reading my way through the code and got confused here and there

Thanks

Regards, Marcus

Hi,

ah, debian, no one has packaged a kernel-obs-build there yet.

Ok, thanks

...

-kernel /var/cache/obs/worker/root_13/.mount/boot/kernel -initrd /var/cache/obs/worker/root_13/.mount/boot/initrd

Even without a kernel-obs-build there is a "boot/Image" and a "boot/initrd" file present in the BUILD_ROOT directory created by obs. In this example:

[ 0s] Using BUILD_ROOT=/obsworker/worker/root_6/.mount

and there are:

/obsworker/worker/root_6/.mount/boot/Image /obsworker/worker/root_6/.mount/boot/initrd

These files do not belong to any package and seems to be copied somehow when the buildservice runs init_buildsystem

Can you help me to understand were they come from ?

Thanks

Regards, Marcus

Hi,

...

and there are:

/obsworker/worker/root_6/.mount/boot/Image
/obsworker/worker/root_6/.mount/boot/initrd

These files do not belong to any package and seems to be copied somehow when the buildservice runs init_buildsystem

Can you help me to understand were they come from ?

they must be part of any package of your distro.

Hmm, I was not able to identify any kernel package from the distro which would provide these files. The distro against the package is build is Debian. If I run

strings /obsworker/worker/root_6/.mount/boot/Image | grep version

I get information like this:

Linux version 5.3.18-na120.2.1-default (geeko@buildhost) (gcc version 10.3.1 20210707 [revision 048117e16c77f82598fca9af585500572d46ad73] (SUSE Linux)) #1 SMP Wed Apr 28 10:54:41 UTC 2021 (ba3c2e9)

It still feels like these files are taken from the worker(Leap 15.2) or from somewhere else. I cannot access the server (only the worker) and I don't understand were this kernel and initrd files comes from.

Any idea ?

Thanks

Regards, Marcus