diff --git a/tools/arch/arm64/include/uapi/asm/kvm.h b/tools/arch/arm64/include/uapi/asm/kvm.h
index a7a857f1784d..f8129c624b07 100644
--- a/tools/arch/arm64/include/uapi/asm/kvm.h
+++ b/tools/arch/arm64/include/uapi/asm/kvm.h
@@ -109,6 +109,7 @@ struct kvm_regs {
 #define KVM_ARM_VCPU_SVE		4 /* enable SVE for this CPU */
 #define KVM_ARM_VCPU_PTRAUTH_ADDRESS	5 /* VCPU uses address authentication */
 #define KVM_ARM_VCPU_PTRAUTH_GENERIC	6 /* VCPU uses generic authentication */
+#define KVM_ARM_VCPU_HAS_EL2		7 /* Support nested virtualization */
 
 struct kvm_vcpu_init {
 	__u32 target;
diff --git a/tools/arch/x86/include/uapi/asm/kvm.h b/tools/arch/x86/include/uapi/asm/kvm.h
index e48deab8901d..7f467fe05d42 100644
--- a/tools/arch/x86/include/uapi/asm/kvm.h
+++ b/tools/arch/x86/include/uapi/asm/kvm.h
@@ -9,6 +9,7 @@
 
 #include <linux/types.h>
 #include <linux/ioctl.h>
+#include <linux/stddef.h>
 
 #define KVM_PIO_PAGE_OFFSET 1
 #define KVM_COALESCED_MMIO_PAGE_OFFSET 2
@@ -507,8 +508,8 @@ struct kvm_nested_state {
 	 * KVM_{GET,PUT}_NESTED_STATE ioctl values.
 	 */
 	union {
-		struct kvm_vmx_nested_state_data vmx[0];
-		struct kvm_svm_nested_state_data svm[0];
+		__DECLARE_FLEX_ARRAY(struct kvm_vmx_nested_state_data, vmx);
+		__DECLARE_FLEX_ARRAY(struct kvm_svm_nested_state_data, svm);
 	} data;
 };
 
@@ -525,6 +526,35 @@ struct kvm_pmu_event_filter {
 #define KVM_PMU_EVENT_ALLOW 0
 #define KVM_PMU_EVENT_DENY 1
 
+#define KVM_PMU_EVENT_FLAG_MASKED_EVENTS BIT(0)
+#define KVM_PMU_EVENT_FLAGS_VALID_MASK (KVM_PMU_EVENT_FLAG_MASKED_EVENTS)
+
+/*
+ * Masked event layout.
+ * Bits   Description
+ * ----   -----------
+ * 7:0    event select (low bits)
+ * 15:8   umask match
+ * 31:16  unused
+ * 35:32  event select (high bits)
+ * 36:54  unused
+ * 55     exclude bit
+ * 63:56  umask mask
+ */
+
+#define KVM_PMU_ENCODE_MASKED_ENTRY(event_select, mask, match, exclude) \
+	(((event_select) & 0xFFULL) | (((event_select) & 0XF00ULL) << 24) | \
+	(((mask) & 0xFFULL) << 56) | \
+	(((match) & 0xFFULL) << 8) | \
+	((__u64)(!!(exclude)) << 55))
+
+#define KVM_PMU_MASKED_ENTRY_EVENT_SELECT \
+	(GENMASK_ULL(7, 0) | GENMASK_ULL(35, 32))
+#define KVM_PMU_MASKED_ENTRY_UMASK_MASK		(GENMASK_ULL(63, 56))
+#define KVM_PMU_MASKED_ENTRY_UMASK_MATCH	(GENMASK_ULL(15, 8))
+#define KVM_PMU_MASKED_ENTRY_EXCLUDE		(BIT_ULL(55))
+#define KVM_PMU_MASKED_ENTRY_UMASK_MASK_SHIFT	(56)
+
 /* for KVM_{GET,SET,HAS}_DEVICE_ATTR */
 #define KVM_VCPU_TSC_CTRL 0 /* control group for the timestamp counter (TSC) */
 #define   KVM_VCPU_TSC_OFFSET 0 /* attribute for the TSC offset */
diff --git a/tools/include/uapi/linux/kvm.h b/tools/include/uapi/linux/kvm.h
index 55155e262646..d77aef872a0a 100644
--- a/tools/include/uapi/linux/kvm.h
+++ b/tools/include/uapi/linux/kvm.h
@@ -583,6 +583,8 @@ struct kvm_s390_mem_op {
 		struct {
 			__u8 ar;	/* the access register number */
 			__u8 key;	/* access key, ignored if flag unset */
+			__u8 pad1[6];	/* ignored */
+			__u64 old_addr;	/* ignored if cmpxchg flag unset */
 		};
 		__u32 sida_offset; /* offset into the sida */
 		__u8 reserved[32]; /* ignored */
@@ -595,11 +597,17 @@ struct kvm_s390_mem_op {
 #define KVM_S390_MEMOP_SIDA_WRITE	3
 #define KVM_S390_MEMOP_ABSOLUTE_READ	4
 #define KVM_S390_MEMOP_ABSOLUTE_WRITE	5
+#define KVM_S390_MEMOP_ABSOLUTE_CMPXCHG	6
+
 /* flags for kvm_s390_mem_op->flags */
 #define KVM_S390_MEMOP_F_CHECK_ONLY		(1ULL << 0)
 #define KVM_S390_MEMOP_F_INJECT_EXCEPTION	(1ULL << 1)
 #define KVM_S390_MEMOP_F_SKEY_PROTECTION	(1ULL << 2)
 
+/* flags specifying extension support via KVM_CAP_S390_MEM_OP_EXTENSION */
+#define KVM_S390_MEMOP_EXTENSION_CAP_BASE	(1 << 0)
+#define KVM_S390_MEMOP_EXTENSION_CAP_CMPXCHG	(1 << 1)
+
 /* for KVM_INTERRUPT */
 struct kvm_interrupt {
 	/* in */
@@ -1175,6 +1183,7 @@ struct kvm_ppc_resize_hpt {
 #define KVM_CAP_DIRTY_LOG_RING_ACQ_REL 223
 #define KVM_CAP_S390_PROTECTED_ASYNC_DISABLE 224
 #define KVM_CAP_DIRTY_LOG_RING_WITH_BITMAP 225
+#define KVM_CAP_PMU_EVENT_MASKED_EVENTS 226
 
 #ifdef KVM_CAP_IRQ_ROUTING