Andrey Drobyshev <[email protected]> writes: > The savevm/loadvm operation doesn't make any sense in any of the CPR > modes. Saving VM state implies saving its RAM entirely, while the whole > point of CPR is avoiding that: in cpr-transfer and cpr-exec modes RAM is > preserved in place and never put into the migration stream (see > migrate_ram_is_ignored() in migration/ram.c). As a result, a snapshot > taken with such a mode set has no RAM in it, and loading a snapshot with > such a mode set fails in the RAM loader. > > Currently nothing stops these operations from firing with a CPR mode > still set, e.g. after an earlier CPR attempt. Reject them early in > migrate_can_snapshot(), which guards 'savevm'/'loadvm' HMP commands as > well as 'snapshot-save'/'snapshot-load' QMP commands. > > Signed-off-by: Andrey Drobyshev <[email protected]> > --- > migration/options.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/migration/options.c b/migration/options.c > index 05b026f4bf2..f648be1302b 100644 > --- a/migration/options.c > +++ b/migration/options.c > @@ -555,8 +555,15 @@ static bool migrate_incoming_started(void) > bool migrate_can_snapshot(Error **errp) > { > MigrationState *s = migrate_get_current(); > + MigMode mode = migrate_mode(); > int i; > > + if (mode != MIG_MODE_NORMAL) { > + error_setg(errp, "Snapshots are not compatible with migration mode > %s", > + MigMode_str(mode)); > + return false; > + } > + > for (i = 0; i < check_caps_savevm.size; i++) { > int incomp_cap = check_caps_savevm.caps[i];
+CC Akihiko Odaki Reviewed-by: Fabiano Rosas <[email protected]>
