Currently, we don't have an exit reason to notify user space about a system-level event (for e.g. system reset or shutdown) triggered by the VCPU. This patch adds exit reason KVM_EXIT_SYSTEM_EVENT for this purpose. We can also inform user space about the 'type' and architecture specific 'flags' of a system-level event using the kvm_run structure.
This newly added KVM_EXIT_SYSTEM_EVENT will be used by KVM ARM/ARM64 in-kernel PSCI v0.2 support to reset/shutdown VMs.
Signed-off-by: Anup Patel anup.patel@linaro.org Signed-off-by: Pranavkumar Sawargaonkar pranavkumar@linaro.org Reviewed-by: Christoffer Dall christoffer.dall@linaro.org --- Documentation/virtual/kvm/api.txt | 15 +++++++++++++++ include/uapi/linux/kvm.h | 8 ++++++++ 2 files changed, 23 insertions(+)
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index 0114d5b..e675ec2 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -2721,6 +2721,21 @@ It gets triggered whenever both KVM_CAP_PPC_EPR are enabled and an external interrupt has just been delivered into the guest. User space should put the acknowledged interrupt vector into the 'epr' field.
+ /* KVM_EXIT_SYSTEM_EVENT */ + struct { +#define KVM_SYSTEM_EVENT_SHUTDOWN 1 +#define KVM_SYSTEM_EVENT_RESET 2 + __u32 type; + __u64 flags; + } system_event; + +If exit_reason is KVM_EXIT_SYSTEM_EVENT then the vcpu has triggered +a system-level event using some architecture specific mechanism (hypercall +or some special instruction). In case of ARM/ARM64, this is triggered using +HVC instruction based PSCI call from the vcpu. The 'type' field describes +the system-level event type. The 'flags' field describes architecture +specific flags for the system-level event. + /* Fix the size of the union. */ char padding[256]; }; diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 260d3ae..0cf2882 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -171,6 +171,7 @@ struct kvm_pit_config { #define KVM_EXIT_WATCHDOG 21 #define KVM_EXIT_S390_TSCH 22 #define KVM_EXIT_EPR 23 +#define KVM_EXIT_SYSTEM_EVENT 24
/* For KVM_EXIT_INTERNAL_ERROR */ /* Emulate instruction failed. */ @@ -301,6 +302,13 @@ struct kvm_run { struct { __u32 epr; } epr; + /* KVM_EXIT_SYSTEM_EVENT */ + struct { +#define KVM_SYSTEM_EVENT_SHUTDOWN 1 +#define KVM_SYSTEM_EVENT_RESET 2 + __u32 type; + __u64 flags; + } system_event; /* Fix the size of the union. */ char padding[256]; };