[pve-devel] partially-applied: [PATCH-SERIES qemu-server 00/31] preparation for blockdev, part three

[Fabian Grünbichler]

On June 25, 2025 5:56 pm, Fiona Ebner wrote:
> Changes to OVMF patches (left-over from part two):
> * 01/31 is new
> * keep get_efivars_size() as a wrapper in QemuServer module
> * keep early check for CPU bitness in QemuServer module
> * use read-only flag for OVMF code
> * collect some parameters into $hw_info hash, avoid querying AMD-SEV
>   type inside the OVMF module
> 
> Splits out a Network module, qga_check_running(),
> find_vmstate_storage(), QemuMigrate::Helpers, a RunState module with
> the goal of splitting out a BlockJob module, where blockdev_mirror()
> will be added.
> 
> Need some more time to make zeroinit work properly, got an initial
> QEMU patch locally, but need to finalize it. Also need to check why
> exactly block-export-add fails without Alexandre's patch, since we do
> query the node name there. We shouldn't use the top node there in any
> case, because we don't want to be limited by limits intended for the
> guest during migration.
> 
> Therefore, the patches from 24/31 onwards are RFC, not finalized, just
> for context and easier testing for reviewers.

applied the non-RFC part (didn't do in-depth testing, but the changes
are sensible)

some follow-ups that would be nice to have, as discussed off-list:

- get rid of the small (pre-existing!) back-reference from Drive.pm to
  QemuConfig.pm, by making the is_template bool a part of hw_info for
  OVMF purposes, and the helper in Drive.pm just return whether setting
  to read-only is possible.
- reduce the public interface of BlockJob.pm to just `mirror`, `monitor`
  and `cancel`
- make the names of subs in BlockJob shorter, the context is already
  there via the fully qualified name for external callers, and by virtue
  of being in the module for private subs
- adapt the interface of qemu_drive_mirror to match the blockdev/public
  ones (i.e., use source and dest info and options)

  very nice work, we are now at 15% line count reduction for
  QemuServer.pm already!