threeeye
bc1d038eac
Squashed backup commit (no shallow-clone history issues) of xiaomi-mt6833-dev/kernel_xiaomi_mt6833 (lineage-23.2 branch, upstream commit 9eece662e) plus all fixes applied to get everpal_defconfig building clean against a modern (GCC 15.2.0) toolchain -- see the previous commit message on the lineage-23.2 branch (also in this repo history is not available here since this is a squashed snapshot; full incremental history lives in the local DL380 checkout and the upstream GitHub remote). Upstream: https://github.com/xiaomi-mt6833-dev/kernel_xiaomi_mt6833 (lineage-23.2)
31 lines
1.3 KiB
Plaintext
31 lines
1.3 KiB
Plaintext
KVM implements the PSCI (Power State Coordination Interface)
|
|
specification in order to provide services such as CPU on/off, reset
|
|
and power-off to the guest.
|
|
|
|
The PSCI specification is regularly updated to provide new features,
|
|
and KVM implements these updates if they make sense from a virtualization
|
|
point of view.
|
|
|
|
This means that a guest booted on two different versions of KVM can
|
|
observe two different "firmware" revisions. This could cause issues if
|
|
a given guest is tied to a particular PSCI revision (unlikely), or if
|
|
a migration causes a different PSCI version to be exposed out of the
|
|
blue to an unsuspecting guest.
|
|
|
|
In order to remedy this situation, KVM exposes a set of "firmware
|
|
pseudo-registers" that can be manipulated using the GET/SET_ONE_REG
|
|
interface. These registers can be saved/restored by userspace, and set
|
|
to a convenient value if required.
|
|
|
|
The following register is defined:
|
|
|
|
* KVM_REG_ARM_PSCI_VERSION:
|
|
|
|
- Only valid if the vcpu has the KVM_ARM_VCPU_PSCI_0_2 feature set
|
|
(and thus has already been initialized)
|
|
- Returns the current PSCI version on GET_ONE_REG (defaulting to the
|
|
highest PSCI version implemented by KVM and compatible with v0.2)
|
|
- Allows any PSCI version implemented by KVM and compatible with
|
|
v0.2 to be set with SET_ONE_REG
|
|
- Affects the whole VM (even if the register view is per-vcpu)
|