diff --git a/qemu/target-mips/op_helper.c b/qemu/target-mips/op_helper.c
index 5ffc212d..26dd624b 100644
--- a/qemu/target-mips/op_helper.c
+++ b/qemu/target-mips/op_helper.c
@@ -660,7 +660,7 @@ static void sync_c0_tcstatus(CPUMIPSState *cpu, int tc,
 
     /* Sync the TASID with EntryHi.  */
     cpu->CP0_EntryHi &= ~0xff;
-    cpu->CP0_EntryHi = tasid;
+    cpu->CP0_EntryHi |= tasid;
 
     compute_hflags(cpu);
 }