Re: [PATCH docs/manager/qemu-server v4 00/17] Add API and UI for custom CPU models

[David Riley <d.riley@proxmox.com>]

Thanks for the patch. This seems to be a nice addition.

I’ve tested the series and found a regression in the VM creation
wizard. When creating a Windows guest with the 'Add additional drive
for VirtIO drivers' checkbox enabled and an ISO Image is added,
the creation fails with:

'Parameter verification failed. (400) ide0:
explicit media=cdrom is required for iso images'

Looking at the request payload, the 'media=cdrom' property is missing
for the VirtIO ISO:

   Before: ide0: "sani:iso/virtio-win-0.1.271.iso,media=cdrom"
   Now: ide0: "sani:iso/virtio-win-0.1.271.iso"

I also noticed that the wizard now defaults to the IDE bus for disks
instead of SCSI, when the Guest OS Type Microsoft Windows is selected.


On 4/30/26 5:59 PM, Arthur Bied-Charreton wrote:
> This picks up and extends an old series [0] by Stefan Reiter.
>
> This series adds a full CRUD API and a UI editor for custom CPU models
> which allows users to manage them in the Datacenter interface rather
> than editing /etc/pve/virtual-guest/cpu-models.conf manually.
>
> It also improves on the existing VM CPU flags selector by providing a
> list of nodes supporting each flag to help gauge cluster compatibility.
>
> qemu-server gets a new CPUFlags module grouping cpu-flags-related
> helpers. A new helper (query_available_cpu_flags) is introduced, which
> derives the set of flags accepted by QEMU as -cpu arguments and
> annotates each with the cluster nodes that report supporting it. The
> existing node-level endpoint is extended with an accel parameter to
> filter flags by acceleration type. Its default behavior is preserved
> modulo the added 'supported-on' field per flag in the return value.
>
> pve-manager gets two new cluster-level endpoints:
>
> 1. /cluster/qemu/cpu-flags queries flags available across the cluster
>     and reports which node supports each of them. It differs from the
>     node-level endpoint in qemu-server in that it returns *all* flags,
>     as opposed to the VM-specific ones.
>
> 2. /cluster/qemu/custom-cpu-models provides full CRUD for custom CPU
>     model definitions.
>
> The UI gets a "Custom CPU models" view in the Datacenter panel (at the
> bottom under "Guest Resources/Hardware") with an editor for model
> properties. The flags can now be filtered by acceleration type when
> creating a new VM or custom CPU model, and it is pre-selected based on
> the VM's KVM config key when editing a pre-existing VM's CPU. The CPU
> flags selector is also improved with the option to filter out flags
> that are not supported anywhere in the cluster.
>
> Dependencies:
>   pve-manager requires bumped pve-docs
>   pve-manager requires bumped qemu-server
>
> Changes since v1:
>   - Reorder patches according to dependency directions
>
>   qemu-server:
>    - Rebase
>    - Add preparatory commit renaming $default_filename to
>      $cpu_models_filename
>    - Squash helpers into commits with their first users
>    - Drop unrelated formatting change
>    - Move cluster-wide cpu-flags to pve-manager, related changes in
>      pve-manager changelog, keep vm-specific cpu-flags endpoint
>    - Return all flags from cpu-flags endpoint, not only the ones with at
>      least one node supporting them - allow filtering for that in the UI
>    - Return only VM-specific cpu-flags by default in node-specific endpoint
>    - Add acceleration type filter to cpu-flags endpoint, defaulting to kvm
>    - Document why no flags are currently returned for aarch64
>    - Only add nested-virt to flags for hosts that support one of svm/vmx
>    - Rename extract_flags to query_available_cpu_flags
>    - Remove web references from doc comments
>    - Refactor query_available_cpu_flags to a more imperative style
>    - Move custom CPU models CRUD endpoints to pve-manager, related changes
>      in pve-manager changelog
>    - Introduce QemuServer::CPUFlags module grouping flags-related helpers
>    - Add flag_is_aliased helper to identify flags covered by nested-virt
>
>   pve-manager:
>    - Rebase
>    - Drop unneeded dirty state fix from original series
>    - Update unknown flags behavior to
>      1. Show unknown flags at the top of the list in the UI
>      2. Add a description to unknown flags signaling that the flag is not
>      recognized in the cluster/for the currently selected acceleration type
>    - Rename allowCustom CPU model selector config field to showCustomModels
>    - Change "Reported Model" to "Base Model" in the UI
>    - Link directly to "CPU Type" section in onlineHelp refs
>    - Improve message in remove confirm dialog for custom CPU models
>    - Move "Custom CPU Models" further down in Datacenter menu, and group it
>      with "{Directory,Resource} Mappings" under "Guest Resources/Hardware"
>    - Default VM-specific CPU flags selection to KVM during creation, and
>      pre-select/lock it based on the VM's configured acceleration when
>      editing
>    - Remove hardcoded list of VM-specific flags in frontend
>    - Change 'Set' to 'Value' in VMCpuFlagSelector
>    - Use "" instead of `` for user-facing strings
>    - Add search bar for long lists of CPU flags
>    - Return all flags from the backend, not only the ones with at least one
>      node supporting them - allow filtering for that in the UI
>    - Show svm/vmx in cpu-flags list regardless of overlap with nested-virt
>    - Add endpoint for querying CPU flags cluster-wide
>    (`/cluster/qemu/cpu-flags`)
>    - Document missing supported flags for `aarch64`
>    - Add CRUD endpoint for custom CPU models
>    (`/cluster/qemu/custom-cpu-models`)
>
>   pve-docs:
>    - Add qm_cpu_type anchor to CPU Type section in qm.adoc
>
> Changes since v2:
>   - Rebase all repos
>   - Remove JS component names from commit subjects
>
>   pve-manager:
>    - Avoid losing flags that were set while "Show only flags supported by
>      at least one node" was not checked when checking it again
>    - Avoid overwriting the whole extraParams in setArch
>
> Changes since v3:
>   - Fix custom CPU model create requests by cleaning empty optional
>     values in the input panel value hook and dropping the unsupported
>     delete param on create
>
> [0] https://lore.proxmox.com/pve-devel/20211028114150.3245864-1-s.reiter@proxmox.com/
>
>
> pve-docs:
>
> Arthur Bied-Charreton (1):
>    qm: add anchor to "CPU Type" section
>
>   qm.adoc | 1 +
>   1 file changed, 1 insertion(+)
>
>
> qemu-server:
>
> Arthur Bied-Charreton (7):
>    cpu config: rename CPU models config path variable
>    cpu flags: move cpu flags-related utilities to their own module
>    cpu flags: add helper querying CPU flags with nodes supporting them
>    cpu config: add helpers to lock and write config
>    cpu: register standard option for CPU format
>    cpu config: set 'type' field before writing
>    cpu flags: improve flags list returned by endpoint
>
>   src/PVE/API2/Qemu/CPUFlags.pm   |  27 +++-
>   src/PVE/QemuServer.pm           |  24 +---
>   src/PVE/QemuServer/CPUConfig.pm | 110 +++------------
>   src/PVE/QemuServer/CPUFlags.pm  | 230 ++++++++++++++++++++++++++++++++
>   src/PVE/QemuServer/Makefile     |   1 +
>   5 files changed, 280 insertions(+), 112 deletions(-)
>   create mode 100644 src/PVE/QemuServer/CPUFlags.pm
>
>
> pve-manager:
>
> Arthur Bied-Charreton (9):
>    api: add endpoint querying available CPU flags cluster-wide
>    api: add CRUD handlers for custom CPU models
>    ui: cpu model selector: allow filtering out custom models
>    ui: add basic custom CPU model editor
>    ui: cpu flags selector: add CPU flag editor for custom models
>    ui: cpu flags selector: fix buffered rendering error
>    ui: cpu flags selector: allow filtering out flags supported on 0 nodes
>    ui: cpu flags selector: add search bar for large lists of flags
>    RFC: ui: group custom CPU with resource mappings
>
>   PVE/API2/Cluster.pm                      |   7 +
>   PVE/API2/Cluster/Makefile                |   4 +-
>   PVE/API2/Cluster/Qemu.pm                 |  47 ++++
>   PVE/API2/Cluster/Qemu/CPUFlags.pm        |  68 +++++
>   PVE/API2/Cluster/Qemu/CustomCPUModels.pm | 211 ++++++++++++++++
>   PVE/API2/Cluster/Qemu/Makefile           |  18 ++
>   www/css/ext6-pve.css                     |   4 +
>   www/manager6/Makefile                    |   3 +
>   www/manager6/dc/CPUTypeEdit.js           | 105 ++++++++
>   www/manager6/dc/CPUTypeView.js           | 149 +++++++++++
>   www/manager6/dc/Config.js                |  27 ++
>   www/manager6/form/CPUModelSelector.js    |  11 +
>   www/manager6/form/PhysBitsSelector.js    | 153 +++++++++++
>   www/manager6/form/VMCPUFlagSelector.js   | 308 ++++++++++++++++++++---
>   www/manager6/qemu/ProcessorEdit.js       |   6 +
>   15 files changed, 1090 insertions(+), 31 deletions(-)
>   create mode 100644 PVE/API2/Cluster/Qemu.pm
>   create mode 100644 PVE/API2/Cluster/Qemu/CPUFlags.pm
>   create mode 100644 PVE/API2/Cluster/Qemu/CustomCPUModels.pm
>   create mode 100644 PVE/API2/Cluster/Qemu/Makefile
>   create mode 100644 www/manager6/dc/CPUTypeEdit.js
>   create mode 100644 www/manager6/dc/CPUTypeView.js
>   create mode 100644 www/manager6/form/PhysBitsSelector.js
>
>
> Summary over all repositories:
>    21 files changed, 1371 insertions(+), 143 deletions(-)
>