Requirements for different kernels

[rgov]

Is there any guidance on what is required of a kernel to be able to boot and run containers?

I found that vmlinuz-6.17.0-4-generic from Ubuntu could not boot; apparently Virtualization.framework does not support compressed kernel images. I had no luck with the extract-linux tool but could do it with Python:

% python3 -c "import sys; data=open(sys.argv[1],'rb').read(); I=d.index(b'\x28\xb5\x2f\xfd'); sys.stdout.buffer.write(d[i:])" \
    vmlinuz-6.17.0-4-generic | unzstd > vmlinux

This boots, but vminitd crashes:

1970-01-01T00:00:01+0000 info vminitd : [vminitd] checking for shim var FOREGROUND=nil
1970-01-01T00:00:01+0000 info vminitd : [vminitd] running vminitd under pid1
1970-01-01T00:00:01+0000 info vminitd : [vminitd] checking for shim var FOREGROUND=Optional("1")
Swift/ErrorType.swift:254: Fatal error: Error raised at top level: Error Domain=NSPOSIXErrorDomain Code=19 "No such device"
Current stack trace:
0    <unknown>                          0x0000000003e53c8c
1    <unknown>                          0x0000000003ef7a8c
2    <unknown>                          0x0000000003b5e3a0
3    <unknown>                          0x0000000003ce594c
4    <unknown>                          0x0000000003d38f54
5    <unknown>                          0x0000000003ad39b8
6    <unknown>                          0x0000000003f40b20
7    <unknown>                          0x0000000003f41dd4
8    <unknown>                          0x0000000003ad489c

I'm not sure how to symbolicate the crash log.

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Edit: There is some guidance here:

• Containerization allows user provided kernels but tests functionality starting with kernel version 6.14.9.
• Containerization provides an optimized kernel configuration located in the kernel directory.
• If you wish to consume a pre-built kernel, make sure it has VIRTIO drivers compiled into the kernel (not merely as modules).