diff --git a/riscv/fdt.c b/riscv/fdt.c
index cc8070d..418b668 100644
--- a/riscv/fdt.c
+++ b/riscv/fdt.c
@@ -48,6 +48,7 @@
 	{"zksed", KVM_RISCV_ISA_EXT_ZKSED},
 	{"zksh", KVM_RISCV_ISA_EXT_ZKSH},
 	{"zkt", KVM_RISCV_ISA_EXT_ZKT},
+	{"ztso", KVM_RISCV_ISA_EXT_ZTSO},
 	{"zvbb", KVM_RISCV_ISA_EXT_ZVBB},
 	{"zvbc", KVM_RISCV_ISA_EXT_ZVBC},
 	{"zvfh", KVM_RISCV_ISA_EXT_ZVFH},
diff --git a/riscv/include/kvm/kvm-config-arch.h b/riscv/include/kvm/kvm-config-arch.h
index e562d71..7cfbf30 100644
--- a/riscv/include/kvm/kvm-config-arch.h
+++ b/riscv/include/kvm/kvm-config-arch.h
@@ -121,6 +121,9 @@
 	OPT_BOOLEAN('\0', "disable-zkt",				\
 		    &(cfg)->ext_disabled[KVM_RISCV_ISA_EXT_ZKT],	\
 		    "Disable Zkt Extension"),				\
+	OPT_BOOLEAN('\0', "disable-ztso",				\
+		    &(cfg)->ext_disabled[KVM_RISCV_ISA_EXT_ZTSO],	\
+		    "Disable Ztso Extension"),				\
 	OPT_BOOLEAN('\0', "disable-zvbb",				\
 		    &(cfg)->ext_disabled[KVM_RISCV_ISA_EXT_ZVBB],	\
 		    "Disable Zvbb Extension"),				\