[PATCH 06/16] KVM: Add KVM_EXIT_SYSTEM_EVENT to user space API header

Christoffer Dall
2014-05-25T18:19:22Z

From: Anup Patel <anup.patel@linaro.org>

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>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-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 556d056..6a5de56 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -2740,6 +2740,21 @@ 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 f3252b1..16cb1a1 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];
};
--
1.8.5.2