[Libguestfs] virt-p2v NVMe disks

[Richard W.M. Jones]

On Wed, Nov 04, 2020 at 09:04:44AM +0000, Femi Adegoke wrote:
> virt-p2v hangs & displays the edd message right after I select  which kernel to
> boot into.
> At that point I have to power cycle the pc.
> Yesterday (before I sent you email), it hung a few times but after the 5th
> power cycle it went through.

EDD is an ancient BIOS standard that's not relevant today.  However
the fact it prints "ok" means it should have got past EDD detection
(so I expect edd=off will make no difference) and the kernel is
getting stuck somewhere else.

If you look at where EDD is queried (query_edd ()):

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/x86/boot/main.c#n173

it's just before changing video mode and going into protected mode, so
most likely it's one of those things which is breaking.  Also the EDD
message is the last message printed through BIOS calls which is why it
can appear to hang there even though the boot is continuing and
perhaps stopping much later - you're just losing the later messages.

You might want to try enabling more debug messages or (the ideal way)
adding a serial console to enable you to see all kernel messages.

What hardware is this?  Something very old or unusual?

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
libguestfs lets you edit virtual machines.  Supports shell scripting,
bindings from many languages.  http://libguestfs.org