Comment 10 for bug 2042357

arm64
-----

vm

 SERIES=noble
 ARCH=arm64
 DISK=${SERIES}_${ARCH}.qcow2

 wget https://cloud-images.ubuntu.com/$SERIES/current/${SERIES}-server-cloudimg-${ARCH}.img
 qemu-img create -F qcow2 -b ${SERIES}-server-cloudimg-${ARCH}.img -f qcow2 $DISK 8G

 sudo apt install -y qemu-system-arm qemu-efi

 dd if=/dev/zero of=flash1.img bs=1M count=64
 dd if=/dev/zero of=flash0.img bs=1M count=64
 dd if=/usr/share/qemu-efi/QEMU_EFI.fd of=flash0.img conv=notrunc

 qemu-system-aarch64 \
 -machine virt -cpu cortex-a57 \
 -pflash flash0.img -pflash flash1.img \
 \
 -smp cpus=2 -m 2048 \
 -nodefaults -no-user-config \
 -nographic -serial stdio \
 \
 -drive file=$DISK,if=none,id=drive0 \
 -device virtio-blk-device,drive=drive0 \
 \
 -drive file=test-cidata.iso,media=cdrom \
 \
 -netdev user,hostfwd=::22222-:22,id=net0 \
 -device virtio-net-device,netdev=net0

 $ ssh ubuntu@127.0.0.1 -p 22222

 $ lsb_release -cs
 No LSB modules are available.
 noble

 $ uname -m
 aarch64

 $ uname -rv
 6.5.0-9-generic #9-Ubuntu SMP PREEMPT_DYNAMIC Fri Oct 6 20:34:49 UTC 2023

kdump-tools

 sudo apt update && sudo apt install -y linux-crashdump # No, Yes
 sudo sed 's/crashkernel=[^" ]\+/crashkernel=512M/' -i /etc/default/grub.d/kdump-tools.cfg
 sudo update-grub && sudo reboot

 $ sudo dmesg | grep 'crashkernel reserved:'
 [ 0.000000] crashkernel reserved: 0x0000000091600000 - 0x00000000b1600000 (512 MB)

 $ sudo kdump-config status
  * Invalid symlink : /var/lib/kdump/initrd.img
  * Invalid symlink : /var/lib/kdump/vmlinuz
 current state : Not ready to kdump

 $ sudo kdump-config reload
  * unloaded kdump kernel
  * Creating symlink /var/lib/kdump/vmlinuz
 kdump-tools: Generating /var/lib/kdump/initrd.img-6.5.0-9-generic
  * Creating symlink /var/lib/kdump/initrd.img
  * loaded kdump kernel

 $ sudo kdump-config status
 current state : ready to kdump

crashdump

 $ echo c | sudo tee /proc/sysrq-trigger

 $ find /var/crash
 /var/crash
 /var/crash/202311081722
 /var/crash/202311081722/dmesg.202311081722
 /var/crash/202311081722/dump.202311081722
 /var/crash/kexec_cmd
 /var/crash/kdump_lock
 /var/crash/linux-image-6.5.0-9-generic-202311081722.crash

debug symbols

 dpkg -l | awk '$2 ~ /linux-image-[0-9.-]+-generic/ { print $2, $3}' \
   | while read pkg version; do \
       dbgpkg="linux-image-unsigned-${pkg#linux-image-}-dbgsym"; \
       arch=$(dpkg --print-architecture); \
       wget "https://launchpad.net/ubuntu/+archive/primary/+files/${dbgpkg}_${version}_${arch}.ddeb"; \
     done

 ar p linux-image-unsigned-*-dbgsym_*.ddeb data.tar.xz | tar xJ --wildcards './usr/lib/debug/boot/vmlinux-*-generic'

crash (old)

 $ dpkg -s crash | grep Version:
 Version: 8.0.2-1ubuntu1

 $ crash ./usr/lib/debug/boot/vmlinux-*-generic /var/crash/*/dump.*
 ...
 crash: invalid structure member offset: module_core_size
        FILE: kernel.c LINE: 3781 FUNCTION: module_init()

 [/usr/bin/crash] error trace: aaaac5c23f9c => aaaac58f2f84 => aaaac5974d3c => aaaac59e7330

crash (new)

 sudo add-apt-repository -y ppa:mfo/noble-crash-v2 && sudo apt install -y crash

 $ dpkg -s crash | grep Version:
 Version: 8.0.3+ds1-3ubuntu1

 $ crash ./usr/lib/debug/boot/vmlinux-*-generic /var/crash/*/dump.*
 ...
 WARNING: active task ffff000041b7e480 on cpu 0 not found in PID hash
 WARNING: active task ffff000040104300 on cpu 1 not found in PID hash

       KERNEL: ./usr/lib/debug/boot/vmlinux-6.5.0-9-generic
     DUMPFILE: /var/crash/202311081722/dump.202311081722 [PARTIAL DUMP]
  CPUS: 2
  DATE: Wed Nov 8 17:17:27 UTC 2023
       UPTIME: 01:25:18
 LOAD AVERAGE: 0.27, 0.11, 0.16
        TASKS: 4
     NODENAME: test
      RELEASE: 6.5.0-9-generic
      VERSION: #9-Ubuntu SMP PREEMPT_DYNAMIC Fri Oct 6 20:34:49 UTC 2023
      MACHINE: aarch64 (unknown Mhz)
       MEMORY: 2.1 GB
        PANIC: "Kernel panic - not syncing: sysrq triggered crash"
   PID: 5111
      COMMAND: "tee"
  TASK: ffff000041b7e480 [THREAD_INFO: ffff000041b7e480]
   CPU: 0
        STATE: TASK_RUNNING (PANIC)

 crash> bt
 PID: 5111 TASK: ffff000041b7e480 CPU: 0 COMMAND: "tee"
  #0 [ffff80008404b8d0] machine_kexec at ffff800080182cf0
  #1 [ffff80008404ba60] __crash_kexec at ffff80008033b2d8
  #2 [ffff80008404bae0] panic at ffff800080206920
  #3 [ffff80008404bb70] sysrq_handle_crash at ffff800080e4d65c
  #4 [ffff80008404bb80] __handle_sysrq at ffff800080e4e420
  #5 [ffff80008404bbf0] write_sysrq_trigger at ffff800080e4efb8
  #6 [ffff80008404bc10] proc_reg_write at ffff8000806fad50
  #7 [ffff80008404bc90] vfs_write at ffff8000806246b0
  #8 [ffff80008404bce0] ksys_write at ffff800080624b2c
  #9 [ffff80008404bd10] __arm64_sys_write at ffff800080624c14
 #10 [ffff80008404be00] invoke_syscall at ffff800080173d30
 #11 [ffff80008404be30] el0_svc_common.constprop.0 at ffff800080173e38
 #12 [ffff80008404be60] do_el0_svc at ffff800080173f7c
 #13 [ffff80008404be80] el0_svc at ffff80008167d934
 #14 [ffff80008404bea0] el0t_64_sync_handler at ffff80008167dfdc
 #15 [ffff80008404bfe0] el0t_64_sync at ffff800080151e44
 ...
 crash> quit