[PATCH v10 3/5] arm/arm64: KVM: Introduce set and get per-vcpu event

From: Dongjiu Geng
Date: Sat Mar 03 2018 - 03:04:12 EST


RAS Extension provides VSESR_EL2 register to specify
virtual SError syndrome value, this patch adds a new
IOCTL to export user-invisible states related to
SError exceptions. User space can setup the
kvm_vcpu_events to inject specified SError, also it
can support live migration.

Signed-off-by: Dongjiu Geng <gengdongjiu@xxxxxxxxxx>
---
Documentation/virtual/kvm/api.txt | 26 ++++++++++++++++++++++++--
arch/arm/include/asm/kvm_host.h | 6 ++++++
arch/arm/kvm/guest.c | 12 ++++++++++++
arch/arm64/include/asm/kvm_host.h | 5 +++++
arch/arm64/include/uapi/asm/kvm.h | 10 ++++++++++
arch/arm64/kvm/guest.c | 26 ++++++++++++++++++++++++++
arch/arm64/kvm/reset.c | 1 +
virt/kvm/arm/arm.c | 18 ++++++++++++++++++
8 files changed, 102 insertions(+), 2 deletions(-)

diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index 8a3d708..26ae151 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -819,11 +819,13 @@ struct kvm_clock_data {

Capability: KVM_CAP_VCPU_EVENTS
Extended by: KVM_CAP_INTR_SHADOW
-Architectures: x86
+Architectures: x86, arm, arm64
Type: vm ioctl
Parameters: struct kvm_vcpu_event (out)
Returns: 0 on success, -1 on error

+X86:
+
Gets currently pending exceptions, interrupts, and NMIs as well as related
states of the vcpu.

@@ -865,15 +867,29 @@ Only two fields are defined in the flags field:
- KVM_VCPUEVENT_VALID_SMM may be set in the flags field to signal that
smi contains a valid state.

+ARM, ARM64:
+
+Gets currently pending SError exceptions as well as related states of the vcpu.
+
+struct kvm_vcpu_events {
+ struct {
+ bool serror_pending;
+ bool serror_has_esr;
+ u64 serror_esr;
+ } exception;
+};
+
4.32 KVM_SET_VCPU_EVENTS

Capability: KVM_CAP_VCPU_EVENTS
Extended by: KVM_CAP_INTR_SHADOW
-Architectures: x86
+Architectures: x86, arm, arm64
Type: vm ioctl
Parameters: struct kvm_vcpu_event (in)
Returns: 0 on success, -1 on error

+X86:
+
Set pending exceptions, interrupts, and NMIs as well as related states of the
vcpu.

@@ -894,6 +910,12 @@ shall be written into the VCPU.

KVM_VCPUEVENT_VALID_SMM can only be set if KVM_CAP_X86_SMM is available.

+ARM, ARM64:
+
+Set pending SError exceptions as well as related states of the vcpu.
+
+See KVM_GET_VCPU_EVENTS for the data structure.
+

4.33 KVM_GET_DEBUGREGS

diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
index ef54013..d81621e 100644
--- a/arch/arm/include/asm/kvm_host.h
+++ b/arch/arm/include/asm/kvm_host.h
@@ -211,6 +211,12 @@ struct kvm_vcpu_stat {
int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices);
int kvm_arm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg);
int kvm_arm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg);
+int kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu,
+ struct kvm_vcpu_events *events);
+
+int kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu,
+ struct kvm_vcpu_events *events);
+
unsigned long kvm_call_hyp(void *hypfn, ...);
void force_vm_exit(const cpumask_t *mask);

diff --git a/arch/arm/kvm/guest.c b/arch/arm/kvm/guest.c
index 1e0784e..39f895d 100644
--- a/arch/arm/kvm/guest.c
+++ b/arch/arm/kvm/guest.c
@@ -248,6 +248,18 @@ int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
return -EINVAL;
}

+int kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu,
+ struct kvm_vcpu_events *events)
+{
+ return -EINVAL;
+}
+
+int kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu,
+ struct kvm_vcpu_events *events)
+{
+ return -EINVAL;
+}
+
int __attribute_const__ kvm_target_cpu(void)
{
switch (read_cpuid_part()) {
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 3dc49b7..1125540 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -326,6 +326,11 @@ struct kvm_vcpu_stat {
int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices);
int kvm_arm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg);
int kvm_arm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg);
+int kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu,
+ struct kvm_vcpu_events *events);
+
+int kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu,
+ struct kvm_vcpu_events *events);

#define KVM_ARCH_WANT_MMU_NOTIFIER
int kvm_unmap_hva(struct kvm *kvm, unsigned long hva);
diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h
index 9abbf30..32c0eae 100644
--- a/arch/arm64/include/uapi/asm/kvm.h
+++ b/arch/arm64/include/uapi/asm/kvm.h
@@ -39,6 +39,7 @@
#define __KVM_HAVE_GUEST_DEBUG
#define __KVM_HAVE_IRQ_LINE
#define __KVM_HAVE_READONLY_MEM
+#define __KVM_HAVE_VCPU_EVENTS

#define KVM_COALESCED_MMIO_PAGE_OFFSET 1

@@ -153,6 +154,15 @@ struct kvm_sync_regs {
struct kvm_arch_memory_slot {
};

+/* for KVM_GET/SET_VCPU_EVENTS */
+struct kvm_vcpu_events {
+ struct {
+ bool serror_pending;
+ bool serror_has_esr;
+ u64 serror_esr;
+ } exception;
+};
+
/* If you need to interpret the index values, here is the key: */
#define KVM_REG_ARM_COPROC_MASK 0x000000000FFF0000
#define KVM_REG_ARM_COPROC_SHIFT 16
diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c
index 5c7f657..62d49c2 100644
--- a/arch/arm64/kvm/guest.c
+++ b/arch/arm64/kvm/guest.c
@@ -277,6 +277,32 @@ int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
return -EINVAL;
}

+int kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu,
+ struct kvm_vcpu_events *events)
+{
+ events->exception.serror_pending = (vcpu_get_hcr(vcpu) & HCR_VSE);
+ events->exception.serror_has_esr =
+ cpus_have_const_cap(ARM64_HAS_RAS_EXTN) &&
+ (!!vcpu_get_vsesr(vcpu));
+ events->exception.serror_esr = vcpu_get_vsesr(vcpu);
+
+ return 0;
+}
+
+int kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu,
+ struct kvm_vcpu_events *events)
+{
+ bool injected = events->exception.serror_pending;
+ bool has_esr = events->exception.serror_has_esr;
+
+ if (injected && has_esr)
+ kvm_set_sei_esr(vcpu, events->exception.serror_esr);
+ else if (injected)
+ kvm_inject_vabt(vcpu);
+
+ return 0;
+}
+
int __attribute_const__ kvm_target_cpu(void)
{
unsigned long implementor = read_cpuid_implementor();
diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c
index 38c8a64..20e919a 100644
--- a/arch/arm64/kvm/reset.c
+++ b/arch/arm64/kvm/reset.c
@@ -82,6 +82,7 @@ int kvm_arch_dev_ioctl_check_extension(struct kvm *kvm, long ext)
break;
case KVM_CAP_SET_GUEST_DEBUG:
case KVM_CAP_VCPU_ATTRIBUTES:
+ case KVM_CAP_VCPU_EVENTS:
r = 1;
break;
default:
diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c
index 7e3941f..30c56e0 100644
--- a/virt/kvm/arm/arm.c
+++ b/virt/kvm/arm/arm.c
@@ -1051,6 +1051,24 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
return -EFAULT;
return kvm_arm_vcpu_has_attr(vcpu, &attr);
}
+ case KVM_GET_VCPU_EVENTS: {
+ struct kvm_vcpu_events events;
+
+ kvm_arm_vcpu_get_events(vcpu, &events);
+
+ if (copy_to_user(argp, &events, sizeof(struct kvm_vcpu_events)))
+ return -EFAULT;
+
+ return 0;
+ }
+ case KVM_SET_VCPU_EVENTS: {
+ struct kvm_vcpu_events events;
+
+ if (copy_from_user(&events, argp, sizeof(struct kvm_vcpu_events)))
+ return -EFAULT;
+
+ return kvm_arm_vcpu_set_events(vcpu, &events);
+ }
default:
return -EINVAL;
}
--
1.9.1