5001f03269
Doing a rollback via CLI on an LVM storage with 'saferemove' and
'snapshot-as-volume-chain' would run into a locking issue, because
the forked zero-out worker would try to acquire the lock while the
main CLI task is still inside the locked section for
volume_snapshot_rollback_locked(). The same issue does not happen when
the rollback is done via UI. The reason for this can be found in the
note regarding fork_worker():
> we simulate running in foreground if ($self->{type} eq 'cli')
So the worker will be awaited synchronously in CLI context, resulting
in the deadlock, while via API/UI, the main task would move on and
release the lock allowing the zero-out worker to acquire it.
Avoid doing fork_cleanup_worker() inside the locked section to avoid
the issue.
Fixes: 8eabcc7 ("lvm plugin: snapshot-as-volume-chain: use locking for snapshot operations")
Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
Reviewed-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
Link: https://lore.proxmox.com/20251120101742.24843-1-f.ebner@proxmox.com