On 4/28/2026 4:45 PM, Pierrick Bouvier wrote:
> We are getting close to be able to link several targets in a single QEMU 
> system
> binary, and the last obstacle on the road is to embed several TargetInfo in 
> the
> same binary. The end result of this series is to have a single definition for
> target_info symbol.
> 
> This series adds TargetInfo types in QOM, and retrieve them dynamically(). At
> the moment, we don't deal yet with multiple TargetInfo selection, but install
> all that is needed to be able to do it easily.
> 
> Because TargetInfo data is set through class_init, it creates an issue at
> startup, where we may try to instantiate additional (unrelated) types just to
> retrieve the list of "target-info-X" types. Those other types class_init may 
> be
> using target information, to add target specific properties for instance.
> This issue has been fixed by adding a new object_class_get_list_by_name_prefix
> that does not force instantiation of all QOM types, but only those matching a
> specific pattern. This way, we first initialize and retrieve target-info types
> before others.
> 
> An alternative would be to leave all this out of QOM, and use startup
> initializer to add them in a single list. However, because all the 
> single-binary
> work has been using QOM where possible, it would be really sad to not use it 
> for
> this final step. Comments are welcome!
> 
> Finally, sticking to our promise not create a special "single-binary
> configuration", the goal is to use the *exact* same codepath for normal 
> binaries
> also. It means that even for existing system binaries, the goal will be to use
> QOM to retrieve current target, even if there is only one.
> 
> Pierrick Bouvier (6):
>   target-info: extract target_info() definition in target-info-init.h
>   target-info: introduce TargetInfo in QOM
>   system/vl: initialize QOM first
>   qom/object: add object_class_get_list_by_name_prefix
>   target-info-qom: detect target from QOM
>   target-info: replace target_info() in system-mode
> 
>  configs/targets/aarch64-softmmu.c |  6 +--
>  configs/targets/arm-softmmu.c     |  6 +--
>  include/qemu/target-info-init.h   | 63 +++++++++++++++++++++++++++++++
>  include/qemu/target-info-qom.h    | 25 ++++++++++++
>  include/qom/object.h              | 13 +++++++
>  qom/object.c                      | 40 ++++++++++++++++++++
>  system/runstate.c                 |  1 -
>  system/vl.c                       |  5 +++
>  target-info-qom.c                 | 32 ++++++++++++++++
>  target-info-stub.c                |  6 +--
>  10 files changed, 184 insertions(+), 13 deletions(-)
>  create mode 100644 include/qemu/target-info-init.h
>  create mode 100644 include/qemu/target-info-qom.h
> 

Sent v2:
[email protected]

Regards,
Pierrick

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