This series adds a vcpu knob to request a specific PSCI version from KVM via the KVM_REG_ARM_PSCI_VERSION FW register.
The use case for this is to support migration between host kernels that differ in their default (a.k.a. most recent) PSCI version. Note: in order to support PSCI v0.1 we need to drop vcpu initialization with KVM_CAP_ARM_PSCI_0_2 in that case. Alternatively we could limit support to versions >=0.2 . Changes since V5 [5]: * incorporated feedback from Peter * dropped patch that is already upstream Changes since V4 [4]: * incorporated feedback from Peter * added R-B, T-B Changes since V3 [3]: * changed variable name as requested by Eric * added R-B Changes since V2 [2]: * fix kvm_get_psci_version() when the prop is not specified - thanks Eric! * removed the assertion in kvm_get_psci_version() so that this also works with a future kernel/psci version * added R-B Changes since V1 [1]: * incorporated feedback from Peter and Eric [1] https://lore.kernel.org/kvmarm/[email protected]/ [2] https://lore.kernel.org/kvmarm/[email protected]/ [3] https://lore.kernel.org/kvmarm/[email protected]/ [4] https://lore.kernel.org/kvmarm/[email protected]/ [5] https://lore.kernel.org/kvmarm/[email protected]/ Sebastian Ott (1): target/arm/kvm: add kvm-psci-version vcpu property docs/system/arm/cpu-features.rst | 11 ++++++++ target/arm/cpu.c | 8 +++++- target/arm/kvm.c | 48 ++++++++++++++++++++++++++++++-- 3 files changed, 64 insertions(+), 3 deletions(-) -- 2.52.0
