There was recently a discussion regarding CPU model versions. That concept does not fit s390x where we have a lot of feature variability. I proposed an alternative approach in [1], which might work for x86 as well (but I am not sure if x86 still can or wants to switch to that), and requires no real changes in upper layers.
[1] and patch #2 contains more information on the motivation for this. E.g., specifying/expanding "z14-best" will result in the "best feature set possible on this accelerator, hw and, firmware". While a "z13" does not work under TCG and some z/VM versions, "z13-best" will work. As I had a couple of spare minutes this week, I hacked a quick prototype. I did not heavily test this (quick sanity tests under TCG only), but it should be decent enough to get the idea and play with it. I'll not be working next week, which is why I sent this out now for discussion. [1] https://lists.gnu.org/archive/html/qemu-devel/2019-10/msg07222.html Cc: Daniel P. Berrangé <berra...@redhat.com> Cc: Markus Armbruster <arm...@redhat.com> Cc: Jiri Denemark <jdene...@redhat.com> Cc: Eduardo Habkost <ehabk...@redhat.com> Cc: Michael Mueller <m...@linux.ibm.com> David Hildenbrand (2): s390x/cpumodels: Factor out CPU feature dependencies s390x/cpumodel: Introduce "best" model variants target/s390x/cpu-qom.h | 1 + target/s390x/cpu_models.c | 211 +++++++++++++++++++++++++++----------- 2 files changed, 153 insertions(+), 59 deletions(-) -- 2.21.0
