diff --git a/qemu/target/riscv/cpu_helper.c b/qemu/target/riscv/cpu_helper.c
index c4dc6df6..56921d15 100644
--- a/qemu/target/riscv/cpu_helper.c
+++ b/qemu/target/riscv/cpu_helper.c
@@ -500,7 +500,7 @@ void riscv_cpu_do_interrupt(CPUState *cs)
         s = set_field(s, MSTATUS_SPP, env->priv);
         s = set_field(s, MSTATUS_SIE, 0);
         env->mstatus = s;
-        env->scause = cause | ~(((target_ulong)-1) >> async);
+        env->scause = cause | ((target_ulong)async << (TARGET_LONG_BITS - 1));
         env->sepc = env->pc;
         env->sbadaddr = tval;
         env->pc = (env->stvec >> 2 << 2) +