[RFC,0/5] KVM: s390: Add VSIE Interpretation Extension Facility (vsie_sigpif)

Message

Christoph Schlameuss March 18, 2025, 6:59 p.m. UTC

In the upcoming IBM Z machine generation (gen17) the s390x architecture
adds a new VSIE Interpretation Extension Facility (vsie_sigpif) to
improve guest-3 guest performance.

To exploit the new machine support the guest-1 KVM needs to create and
maintain shadow structures pointing to the original state descriptions
and system control areas.
These pointers are followed by the machines firmware and modifications
of the original SCA in guest-3 are monitored and handled by firmware.

---
Christoph Schlameuss (5):
      KVM: s390: Add vsie_sigpif detection
      KVM: s390: Add ssca_block and ssca_entry structs for vsie_ie
      KVM: s390: Shadow VSIE SCA in guest-1
      KVM: s390: Re-init SSCA on switch to ESCA
      KVM: s390: Add VSIE shadow stat counters

 arch/s390/include/asm/kvm_host.h               |  44 +++-
 arch/s390/include/asm/sclp.h                   |   1 +
 arch/s390/kvm/kvm-s390.c                       |   5 +
 arch/s390/kvm/vsie.c                           | 285 ++++++++++++++++++++++++-
 drivers/s390/char/sclp_early.c                 |   1 +
 tools/testing/selftests/kvm/include/s390/sie.h |   2 +-
 6 files changed, 333 insertions(+), 5 deletions(-)
---
base-commit: 4701f33a10702d5fc577c32434eb62adde0a1ae1
change-id: 20250228-vsieie-07be34fc3984

Best regards,