When adding the Reset register in commit 5790b757cfb we
forgot to migrate it.
While it is possible a VM using the PIIX4 is migrated just
after requesting a system shutdown, it is very unlikely.
However when restoring a migrated VM, we might have the
RCR bit #4 set on the stack and when the VM resume it
directly shutdowns.
Add a post_load() migration handler and set the default
RCR value to 0 for earlier versions, assuming the VM was
not going to shutdown before migration.
Fixes: 5790b757cfb ("piix4: Add the Reset Control Register")
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20210324200334.729899-1-f4bug@amsat.org>
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