Live migration not possible from 5.0 to 5.1?

[Antti Antinoja]

Hi All,

I couldn't find any mention about live migration incompatibility between 5.0 
and 5.1 in the release notes but at least on our AMD based platform live 
migration from 5.0 to 5.1 is not possible.

The upgraded host had identical versions with it's pair before the upgrade was 
started:
* qemu 5.0.0-r2
* kernel 5.7.17

After upgrade:
* qemu 5.1.0-r1
* kernel 5.8.16

After reverting qemu back to 5.0.0-r2 migration worked normally.

On the sending end "info migrate" shows:
(qemu) info migrate
info migrate
globals:
store-global-state: on
only-migratable: off
send-configuration: on
send-section-footer: on
decompress-error-check: on
clear-bitmap-shift: 18
Migration status: failed (Unable to write to socket: Broken pipe)
total time: 0 milliseconds

At least once the receiving end died (while running 5.1.0-r1). All attempts 
resulted a "Broken pipe" error on the sending (5.0.0-r2) end.

Cheers,
Antti

-- 
Antti Antinoja <reader@fennosys.fi>