Win11 VM can't stop after ~5min

[gpelz-graph-it]

Using Ubuntu 22.04.5 LTS (5.15.0-130-generic) with lxd from snap

snap-id:      J60k4JY0HppjwOjW8dZdYc8obXKxujRu
tracking:     6.1/stable

I setup a Windows 11 VM following https://ubuntu.com/tutorials/how-to-install-a-windows-11-vm-using-lxd which worked fine.
Sometimes I can't shutdown the vm using lxc stop wm11test.
After some testing I noticed that with lxc start win11test && sleep 260 && lxc stop win11test or lower sleep times starting and shutting down the vm works. Using a time >= 300 like lxc start win11test && sleep 330 && lxc stop win11test it seems like Windows doesn't get or react to the shutdown request. (I can still connect to the vm and shut it down manually.)
Here's what I see using lxc monitor --pretty:

DEBUG  [2025-01-16T13:14:52Z] Handling API request                          ip=@ method=GET protocol=unix url=/1.0 username=root
DEBUG  [2025-01-16T13:14:52Z] Handling API request                          ip=@ method=GET protocol=unix url=/1.0/instances/win11test username=root
DEBUG  [2025-01-16T13:14:52Z] Handling API request                          ip=@ method=GET protocol=unix url=/1.0/events username=root
DEBUG  [2025-01-16T13:14:52Z] Event listener server handler started         id=beec0abf-889a-4d4b-be26-376fe3962443 local=/var/snap/lxd/common/lxd/unix.socket remote=@
DEBUG  [2025-01-16T13:14:52Z] Handling API request                          ip=@ method=PUT protocol=unix url=/1.0/instances/win11test/state username=root
DEBUG  [2025-01-16T13:14:53Z] New operation                                 class=task description="Starting instance" operation=dc9acf02-bbc2-4ed0-bc0f-1e2682a343c3 project=default
DEBUG  [2025-01-16T13:14:53Z] Started operation                             class=task description="Starting instance" operation=dc9acf02-bbc2-4ed0-bc0f-1e2682a343c3 project=default
DEBUG  [2025-01-16T13:14:53Z] Instance operation lock created               action=start instance=win11test project=default reusable=false
DEBUG  [2025-01-16T13:14:53Z] Start started                                 instance=win11test instanceType=virtual-machine project=default stateful=false
INFO   [2025-01-16T13:14:53Z] ID: dc9acf02-bbc2-4ed0-bc0f-1e2682a343c3, Class: task, Description: Starting instance  CreatedAt="2025-01-16 13:14:52.994712085 +0000 UTC" Err= Location=none MayCancel=false Metadata="map[]" Resources="map[instances:[/1.0/instances/win11test]]" Status=Running StatusCode=Running UpdatedAt="2025-01-16 13:14:52.994712085 +0000 UTC"
INFO   [2025-01-16T13:14:53Z] ID: dc9acf02-bbc2-4ed0-bc0f-1e2682a343c3, Class: task, Description: Starting instance  CreatedAt="2025-01-16 13:14:52.994712085 +0000 UTC" Err= Location=none MayCancel=false Metadata="map[]" Resources="map[instances:[/1.0/instances/win11test]]" Status=Pending StatusCode=Pending UpdatedAt="2025-01-16 13:14:52.994712085 +0000 UTC"
DEBUG  [2025-01-16T13:14:53Z] Handling API request                          ip=@ method=GET protocol=unix url=/1.0/operations/dc9acf02-bbc2-4ed0-bc0f-1e2682a343c3 username=root
DEBUG  [2025-01-16T13:14:53Z] MountInstance started                         driver=btrfs instance=win11test pool=default project=default
DEBUG  [2025-01-16T13:14:53Z] MountInstance finished                        driver=btrfs instance=win11test pool=default project=default
DEBUG  [2025-01-16T13:14:53Z] Skipping lxd-agent install as unchanged       installPath=/var/snap/lxd/common/lxd/virtual-machines/win11test/config/lxd-agent instance=win11test instanceType=virtual-machine project=default srcPath=/snap/lxd/30130/bin/lxd-agent
DEBUG  [2025-01-16T13:14:53Z] Starting device                               device=eth0 instance=win11test instanceType=virtual-machine project=default type=nic
DEBUG  [2025-01-16T13:14:53Z] Scheduler: network: tapa1dde8a0 has been added: updating network priorities 
DEBUG  [2025-01-16T13:14:53Z] Starting device                               device=root instance=win11test instanceType=virtual-machine project=default type=disk
DEBUG  [2025-01-16T13:14:53Z] Starting device                               device=vtpm instance=win11test instanceType=virtual-machine project=default type=tpm
WARNING[2025-01-16T13:14:53Z] Using writeback cache I/O                     devPath=/var/snap/lxd/common/lxd/storage-pools/default/virtual-machines/win11test/root.img device=root fsType=btrfs instance=win11test instanceType=virtual-machine project=default
DEBUG  [2025-01-16T13:14:53Z] UpdateInstanceBackupFile started              driver=btrfs instance=win11test pool=default project=default
DEBUG  [2025-01-16T13:14:53Z] UpdateInstanceBackupFile finished             driver=btrfs instance=win11test pool=default project=default
DEBUG  [2025-01-16T13:14:53Z] QMP monitor started                           path=/var/snap/lxd/common/lxd/logs/win11test/qemu.monitor
DEBUG  [2025-01-16T13:14:53Z] Scheduler: virtual-machine win11test started: re-balancing 
INFO   [2025-01-16T13:14:53Z] Action: instance-started, Source: /1.0/instances/win11test, Requestor: unix/root (@) 
INFO   [2025-01-16T13:14:53Z] ID: dc9acf02-bbc2-4ed0-bc0f-1e2682a343c3, Class: task, Description: Starting instance  CreatedAt="2025-01-16 13:14:52.994712085 +0000 UTC" Err= Location=none MayCancel=false Metadata="map[]" Resources="map[instances:[/1.0/instances/win11test]]" Status=Success StatusCode=Success UpdatedAt="2025-01-16 13:14:52.994712085 +0000 UTC"
DEBUG  [2025-01-16T13:14:53Z] Instance operation lock finished              action=start err="<nil>" instance=win11test project=default reusable=false
DEBUG  [2025-01-16T13:14:53Z] Start finished                                instance=win11test instanceType=virtual-machine project=default stateful=false
DEBUG  [2025-01-16T13:14:53Z] Success for operation                         class=task description="Starting instance" operation=dc9acf02-bbc2-4ed0-bc0f-1e2682a343c3 project=default
DEBUG  [2025-01-16T13:14:53Z] Event listener server handler stopped         listener=beec0abf-889a-4d4b-be26-376fe3962443 local=/var/snap/lxd/common/lxd/unix.socket remote=@

DEBUG  [2025-01-16T13:20:23Z] Handling API request                          ip=@ method=GET protocol=unix url=/1.0 username=root
DEBUG  [2025-01-16T13:20:23Z] Handling API request                          ip=@ method=GET protocol=unix url=/1.0/events username=root
DEBUG  [2025-01-16T13:20:23Z] Event listener server handler started         id=03d3ccdc-c362-432a-a3db-4c0614566d9f local=/var/snap/lxd/common/lxd/unix.socket remote=@
DEBUG  [2025-01-16T13:20:23Z] Handling API request                          ip=@ method=PUT protocol=unix url=/1.0/instances/win11test/state username=root
DEBUG  [2025-01-16T13:20:23Z] New operation                                 class=task description="Stopping instance" operation=ae3b9800-210e-458f-b257-3f1efd290410 project=default
INFO   [2025-01-16T13:20:23Z] ID: ae3b9800-210e-458f-b257-3f1efd290410, Class: task, Description: Stopping instance  CreatedAt="2025-01-16 13:20:23.745657275 +0000 UTC" Err= Location=none MayCancel=false Metadata="map[]" Resources="map[instances:[/1.0/instances/win11test]]" Status=Running StatusCode=Running UpdatedAt="2025-01-16 13:20:23.745657275 +0000 UTC"
DEBUG  [2025-01-16T13:20:23Z] Started operation                             class=task description="Stopping instance" operation=ae3b9800-210e-458f-b257-3f1efd290410 project=default
INFO   [2025-01-16T13:20:23Z] ID: ae3b9800-210e-458f-b257-3f1efd290410, Class: task, Description: Stopping instance  CreatedAt="2025-01-16 13:20:23.745657275 +0000 UTC" Err= Location=none MayCancel=false Metadata="map[]" Resources="map[instances:[/1.0/instances/win11test]]" Status=Pending StatusCode=Pending UpdatedAt="2025-01-16 13:20:23.745657275 +0000 UTC"
DEBUG  [2025-01-16T13:20:23Z] Shutdown started                              instance=win11test instanceType=virtual-machine project=default timeout=10m0s
DEBUG  [2025-01-16T13:20:23Z] Instance operation lock created               action=stop instance=win11test project=default reusable=true
DEBUG  [2025-01-16T13:20:23Z] Handling API request                          ip=@ method=GET protocol=unix url=/1.0/operations/ae3b9800-210e-458f-b257-3f1efd290410 username=root
DEBUG  [2025-01-16T13:20:23Z] Shutdown request sent to instance             instance=win11test instanceType=virtual-machine project=default

Startup works fine, but no response to the shutdown request. I first thought this might be an issue with older virtio drivers, so I installed https://fedorapeople.org/groups/virt/virtio-win/direct-downloads/archive-virtio/virtio-win-0.1.266-1/virtio-win-0.1.266.iso and restarted the VM, but that didn't help either.

When it's working (smaller sleep timer), one can see a reply a few seconds later.

DEBUG  [2025-01-16T12:12:33Z] Shutdown request sent to instance             instance=win11test instanceType=virtual-machine project=default
DEBUG  [2025-01-16T12:12:38Z] Instance stopped                              instance=win11test instanceType=virtual-machine project=default reason=guest-shutdown target=stop
DEBUG  [2025-01-16T12:12:38Z] Waiting for VM process to finish              instance=win11test instanceType=virtual-machine project=default
DEBUG  [2025-01-16T12:12:38Z] Instance operation lock inherited for stop    action=stop instance=win11test instanceType=virtual-machine project=default
DEBUG  [2025-01-16T12:12:38Z] onStop hook started                           instance=win11test instanceType=virtual-machine project=default target=stop
DEBUG  [2025-01-16T12:12:38Z] QMP monitor stopped                           path=/var/snap/lxd/common/lxd/logs/win11test/qemu.monitor
DEBUG  [2025-01-16T12:12:39Z] VM process finished                           instance=win11test instanceType=virtual-machine project=default
DEBUG  [2025-01-16T12:12:39Z] Stopping device                               device=vtpm instance=win11test instanceType=virtual-machine project=default type=tpm
DEBUG  [2025-01-16T12:12:39Z] Stopping device                               device=root instance=win11test instanceType=virtual-machine project=default type=disk
DEBUG  [2025-01-16T12:12:39Z] Stopping device                               device=eth0 instance=win11test instanceType=virtual-machine project=default type=nic
DEBUG  [2025-01-16T12:12:39Z] UnmountInstance started                       driver=btrfs instance=win11test pool=default project=default
DEBUG  [2025-01-16T12:12:39Z] UnmountInstance finished                      driver=btrfs instance=win11test pool=default project=default
INFO   [2025-01-16T12:12:39Z] Action: instance-shutdown, Source: /1.0/instances/win11test
DEBUG  [2025-01-16T12:12:39Z] onStop hook finished                          instance=win11test instanceType=virtual-machine project=default target=stop
DEBUG  [2025-01-16T12:12:39Z] Instance operation lock finished              action=stop err="<nil>" instance=win11test project=default reusable=true
DEBUG  [2025-01-16T12:12:39Z] Shutdown finished                             instance=win11test instanceType=virtual-machine project=default timeout=10m0s

When it's not working it runs in the 10 minute timeout:

DEBUG  [2025-01-16T13:30:23Z] Shutdown finished                             instance=win11test instanceType=virtual-machine project=default timeout=10m0s
DEBUG  [2025-01-16T13:30:23Z] Failure for operation                         class=task description="Stopping instance" err="Failed shutting down instance, status is \"Running\": context deadline exceeded" operation=ae3b9800-210e-458f-b257-3f1efd290410 project=default
INFO   [2025-01-16T13:30:23Z] ID: ae3b9800-210e-458f-b257-3f1efd290410, Class: task, Description: Stopping instance  CreatedAt="2025-01-16 13:20:23.745657275 +0000 UTC" Err="Failed shutting down instance, status is \"Running\": context deadline exceeded" Location=none MayCancel=false Metadata="map[]" Resources="map[instances:[/1.0/instances/win11test]]" Status=Failure StatusCode=Failure UpdatedAt="2025-01-16 13:20:23.745657275 +0000 UTC"
DEBUG  [2025-01-16T13:30:23Z] Event listener server handler stopped         listener=03d3ccdc-c362-432a-a3db-4c0614566d9f local=/var/snap/lxd/common/lxd/unix.socket remote=@

Am I missing something? Should I install something? Is it a bug? Is there way to specify the fail timeout (10min)?