[PATCH 0/2] KVM: arm64: Reject mismatched GICv3 ITS/VGIC models

[Sascha Bischoff <sascha.bischoff@arm.com>]

On a GICv5 host with legacy GICv3 support, KVM exposes both VGIC
models to userspace. A VM can create a GICv3 ITS alongside a GICv5
VGIC, because neither creation path checks the model of the other
device. The ITS sets has_its, but a GICv5 VM cannot use a GICv3 ITS
for MSI translation. Creating the ITS before the VGIC also lets
userspace select an incompatible VGIC model later.

Record the VGIC model required by a GICv3 ITS and reject incompatible
device creation in either order. The second patch tests both orderings,
skipping the test if the host does not offer a GICv3 ITS.

This series is based on kvmarm/next-7.4+fixes-7.3-2.

Sascha

Sascha Bischoff (2):
  KVM: arm64: vgic: Require matching VGIC model for GICv3 ITS
  KVM: selftests: Reject GICv3 ITS with a GICv5 VGIC

 arch/arm64/kvm/vgic/vgic-init.c             |  5 ++++
 arch/arm64/kvm/vgic/vgic-its.c              |  9 ++++++
 include/kvm/arm_vgic.h                      |  2 ++
 tools/testing/selftests/kvm/arm64/vgic_v5.c | 32 +++++++++++++++++++++
 4 files changed, 48 insertions(+)


base-commit: 678f16b6e4767096aa3e3e6eef60e981b3f61e12
-- 
2.34.1