Skip to content

ppc 'max' CPU model is unlike the other targets 'max' CPU model

Host environment

  • QEMU flavor: qemu-system-ppc64
  • QEMU version: QEMU emulator version 6.2.0 (qemu-6.2.0-9.fc36)
  • QEMU command line:
$ qemu-system-ppc64 -cpu max
qemu-system-ppc64: Unable to find sPAPR CPU Core definition

Description of problem

On most targets the 'max' CPU model is either equivalent to 'host' (for KVM) or equivalent to all available CPU features (for TCG).

On PPC64, however, this is not the case. Instead the 'max' model is an alias of the old '7400_v2.9' and simply doesn't work.

This is confusing. At the very least the 'max' model alias should be deleted. Ideally a proper replacement would be introduced that matches semantics on other arches.

Steps to reproduce

  1. qemu-system-ppc64 -cpu max

should be equiv to '-cpu host' or should expose all TCG features.

Edited by Thomas Huth
To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information