Public bug reported:

Howdy! We have noticed that when running 'kexec' on Azure VM's running the 
'6.8.0-1017.20~22.04.1' linux-azure kernel we will see kernel panics. Each 
panic doesn't have the exact same trace which is confusing to me. Here are a 
few I've collected: 
* https://paste.ubuntu.com/p/Vs2VsQvV33/
* https://paste.ubuntu.com/p/yXkN8w6Frh/

I attempted to downgrade to the linux-azure-lts-22.04 5.15.0.1074.72
kernel and to my surprise , the kexec also triggered another panic
there: https://paste.ubuntu.com/p/6Xq89qD8VT//. I've been unable to
reproduce this on the linux-aws and linux-gcp kernels. I've been able to
easily reproduce this behavior on Standard_D8as_v5 and Standard_F32s_v2
instance types. It doesn't appear to matter what kernel args are passed
into the kexec. My go to so far is a simple 'sudo kexec -l /boot/vmlinuz
--command-line="$(cat /proc/cmdline) fake-new-kernel-arg=1" -f' command
which triggers it. It does seem that one of the kernel args needs to
change for this to happen, simply running 'sudo kexec -l /boot/vmlinuz
--command-line="$(cat /proc/cmdline)" -f' doesn't appear to reproduce
the panics. It looks like this wasn't a problem on the previous 6.5
linux-azure kernel (which makes the 5.15 repro particularly
surprising...). For reference, we currently use these args:
`BOOT_IMAGE=/boot/vmlinuz-6.8.0-1017-azure root=PARTUUID=uuid-here ro
console=tty1 console=ttyS0 earlyprintk=ttyS0 nvme_core.io_timeout=240
apparmor=1 security=apparmor ipv6.disable=1 transparent_hugepage=madvise
systemd.unified_cgroup_hierarchy=0
systemd.legacy_systemd_cgroup_controller=true panic=-1`

From my testing, eventually the systems will stabilize and stop
panicking but it's been undetermined as to why. I've also noticed cases
where a 'kexec' will happen and not trigger the panics but, that's
seemingly rare. I'd appreciate any help trying to debug this and am more
than happy to provide additional testing/repro info as needed. Thanks!

** Affects: linux-azure (Ubuntu)
     Importance: Undecided
         Status: New

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https://bugs.launchpad.net/bugs/2086789

Title:
  kexec results in kernel panics

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