I turned on grub debugging (set debug=all in grub.cfg), and this seems interesting. The "error: couldn't send network packet." message may actually be telling us something is wrong with downloading the initrd. Full log attached, here's a filtered version:
[...] loader/efi/linux.c:80: UEFI stub kernel: loader/efi/linux.c:81: PE/COFF header @ 00000040 loader/efi/linux.c:95: LoadFile2 initrd loading enabled loader/efi/linux.c:459: kernel file size: 46496128 loader/efi/linux.c:461: kernel numpages: 11352 loader/efi/linux.c:478: kernel @ 0xa1e43000 kern/disk.c:196: Opening `tftp,10.229.58.59'... disk/efi/efidisk.c:482: opening tftp kern/disk.c:281: Opening `tftp,10.229.58.59' failed. kern/disk.c:295: Closing `tftp'. kern/verifiers.c:88: file: /casper/initrd type: 131076 loader/efi/linux.c:396: LoadFile2 initrd loading protocol installed ] loader/efi/linux.c:141: Installed/updated FDT configuration table @ 0x0 loader/efi/linux.c:191: linux command line: 'BOOT_IMAGE=/casper/vmlinuz root=/dev/ram0 ramdisk_size=1500000 ip=dhcp url=http://cdimage.ubuntu.com/ubuntu-server/daily-live/20220408/jammy-live-serv er-arm64.iso --- debug' kern/efi/sb.c:111: UEFI Secure Boot state: Disabled loader/efi/peimage.c:215: PE-COFF header checked loader/efi/peimage.c:282: sections loaded loader/efi/peimage.c:493: no relocations loader/efi/peimage.c:709: Executing image loaded at 0x9f0b0000 Entry point 0xa0fb8428 Size 0x02d90000 EFI stub: Booting Linux Kernel... EFI stub: Generating empty DTB loader/efi/linux.c:348: Providing initrd via LOAD_FILE2_PROTOCOL net/net.c:1596: error receiving: 28: couldn't send network packet net/net.c:1596: error receiving: 28: couldn't send network packet net/net.c:1596: error receiving: 28: couldn't send network packet net/net.c:1596: error receiving: 28: couldn't send network packet net/net.c:1596: error receiving: 28: couldn't send network packet net/net.c:1596: error receiving: 28: couldn't send network packet net/net.c:1596: error receiving: 28: couldn't send network packet net/net.c:1596: error receiving: 28: couldn't send network packet error: couldn't send network packet. EFI stub: Loaded initrd from LINUX_EFI_INITRD_MEDIA_GUID device path EFI stub: Exiting boot services... ** Attachment added: "grub-debug.log" https://bugs.launchpad.net/ubuntu/+source/grub2-unsigned/+bug/1967562/+attachment/5578350/+files/grub-debug.log -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1967562 Title: jammy beta (220330) arm iso pxe boot kernel panic on Ampere Mt. Jade To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/grub2-unsigned/+bug/1967562/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs