diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c
index 504b496787aa4d384e5bae04dc35bf5f104123d7..b4421c16198ca4c74adac055ece15482857f3666 100644
--- a/arch/riscv/kernel/process.c
+++ b/arch/riscv/kernel/process.c
@@ -98,6 +98,15 @@ void start_thread(struct pt_regs *regs, unsigned long pc,
 	}
 	regs->epc = pc;
 	regs->sp = sp;
+
+#ifdef CONFIG_64BIT
+	regs->status &= ~SR_UXL;
+
+	if (is_compat_task())
+		regs->status |= SR_UXL_32;
+	else
+		regs->status |= SR_UXL_64;
+#endif
 }
 
 void flush_thread(void)