Daniel P. Berrangé <berra...@redhat.com> writes: > On Thu, Mar 27, 2025 at 11:39:31AM -0300, Fabiano Rosas wrote: >> It has always been possible to enable arbitrary migration capabilities >> and attempt to take a snapshot of the VM with the savevm/loadvm >> commands as well as their QMP counterparts >> snapshot-save/snapshot-load. >> >> Most migration capabilities are not meant to be used with snapshots >> and there's a risk of crashing QEMU or producing incorrect >> behavior. Ideally, every migration capability would either be >> implemented for savevm or explicitly rejected. > > IMHO, this a prime example of why migration config shouldn't be held > as global state, and instead passed as parameters to the commands > that need them. The snapshot-save/load commands would then only > be able to accept what few settings are actually relevant, instead > of inheriting any/all global migration state. >
Right, I remember we got caught around the fact that some migration options are needed during runtime as well... but I don't remember the details, let try to find that thread. >> Add a compatibility check routine and reject the snapshot command if >> an incompatible capability is enabled. For now only act on the the two >> that actually cause a crash: multifd and mapped-ram. >> >> Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2818 > > Issue is 2881 not 2818 ^^^^^^^ > It seem that was your own C-t =) >> Signed-off-by: Fabiano Rosas <faro...@suse.de> >> --- >> migration/options.c | 26 ++++++++++++++++++++++++++ >> migration/options.h | 1 + >> migration/savevm.c | 8 ++++++++ >> 3 files changed, 35 insertions(+) > > With regards, > Daniel
