Re: [PATCH qemu-server 1/1] fix #8030: snapshot: avoid orphaned vmstate volume on failure

["Jakob Klocker" <j.klocker@proxmox.com>]

Confirmed that an orphaned volume is left behind when the QMP
socket is occupied, causing the snapshot to fail because
`query-machines` times out. After applying the patch, no orphaned
volume remains, which fixes the reported bug.

Not adding additional cleanup, but moving the disk allocation below
the setup functions that can fail is IMO the cleanest solution here.

Consider this:
Reviewed-by: Jakob Klocker <j.klocker@proxmox.com>
Tested-by: Jakob Klocker <j.klocker@proxmox.com>
On Mon Sep 14, 2026 at 4:05 PM CEST, Michael Köppl wrote:
> The state volume was allocated before the running instance was queried
> for its machine type, CPU argument and network MTUs. Those queries can
> fail (e.g. the 'query-machines' QMP command, which can run into a
> timeout while QEMU's is busy [0]).
>
> The helper is called from __snapshot_prepare() before write_config(), so
> the config never records the snapshot, snapshot_create() dies before it
> gets to its cleanup path. Such a failure leaves behind the just
> allocated volume.
>
> Query the running instance first, which makes the allocation the last
> step of the function that can fail.
>
> [0] https://bugzilla.proxmox.com/show_bug.cgi?id=8030
>
> Signed-off-by: Michael Köppl <m.koeppl@proxmox.com>
> [SNIP]