[PATCH v2 0/4] KVM: s390: vsie: Implement ASTFLEIE facility 2

From: Christoph Schlameuss

Date: Thu Feb 26 2026 - 07:52:14 EST


Add support for STFLE format 2 in VSIE guests.

The change requires qemu support to set the ASTFLEIE2 feature bit.
ASTFLEIE2 is available since IBM z16.
To function G1 has to run this KVM code and G1 and G2 have to run QEMU

Tests are implemented in kvm-unit-tests and sent as a series to that
list.

Signed-off-by: Christoph Schlameuss <schlameuss@xxxxxxxxxxxxx>
---
The series was originally developed by Nina and only rebased and
slightly adjusted by me for v1. It was not sent earlier since the accompanying
kvm-unit-tests and qemu changes were not ready.

---
Changes in v2:
- adjusted variable naming in handle_stfle()
- add some constants for readability
- add struct for format-2 facility list control block
- rebased to v7.0-rc1

---
Nina Schoetterl-Glausch (4):
KVM: s390: Minor refactor of base/ext facility lists
s390/sclp: Detect ASTFLEIE 2 facility
KVM: s390: vsie: Refactor handle_stfle
KVM: s390: vsie: Implement ASTFLEIE facility 2

arch/s390/include/asm/kvm_host.h | 9 +++++
arch/s390/include/asm/sclp.h | 1 +
arch/s390/include/uapi/asm/kvm.h | 1 +
arch/s390/kvm/kvm-s390.c | 46 ++++++++++------------
arch/s390/kvm/vsie.c | 85 +++++++++++++++++++++++++++++++---------
drivers/s390/char/sclp_early.c | 4 +-
6 files changed, 101 insertions(+), 45 deletions(-)
---
base-commit: 559f264e403e4d58d56a17595c60a1de011c5e20
change-id: 20260129-vsie-alter-stfle-fac-b3d28b948146

Best regards,
--
Christoph Schlameuss <schlameuss@xxxxxxxxxxxxx>