Re: [Qemu-devel] [PATCH 2/4] migration/savevm: use migration_is_blocked to validate

[Wei Yang]

On Tue, May 14, 2019 at 04:18:14PM +0100, Dr. David Alan Gilbert wrote:
>* Wei Yang (address@hidden) wrote:
>> 
>> Well, when you look into the source side of migration:
>> 
>> qmp_migrate
>>   migrate_prepare
>>     migration_is_blocked
>> 
>> This means if migration_is_blocked fails, the source will not start 
>> migration.
>> And it is the same as save_snapshot.
>> 
>> From my understanding, when we load a vm, it should check the same
>> requirement.
>
>I've been thinking about this, and I think I agree with Daniel on this.
>The 'migration_blockers' list tells you that something about the
>*current* state of a device means that it can't be migrated - e.g.
>a 9pfs with a mounted filesystem can't be migrated.
>
>If we're about to reload the state from a snapshot, then the saved
>snapshot's state must have been migratable, so that's OK.
>

The situation is on a vm with 'migration_blockers' still could reload from a
snapshot.

This sounds reasonable. Thanks :-)

>(Whether all the device code is actually OK about being reset in
>that state is a different question; but I think it should be).
>
>Dave
>
>> -- 
>> Wei Yang
>> Help you, Help me
>--
>Dr. David Alan Gilbert / address@hidden / Manchester, UK

-- 
Wei Yang
Help you, Help me