diff --git a/driver/level2/gbmv_thread.c b/driver/level2/gbmv_thread.c
index e86b565f8..6073a4856 100644
--- a/driver/level2/gbmv_thread.c
+++ b/driver/level2/gbmv_thread.c
@@ -233,6 +233,7 @@ int CNAME(BLASLONG m, BLASLONG n, BLASLONG ku, BLASLONG kl, FLOAT *alpha, FLOAT
 #else
     range_m[num_cpu] = num_cpu * ((n + 15) & ~15);
 #endif
+    if (range_m[num_cpu] > n) range_m[num_cpu] = n;
 
     queue[num_cpu].mode    = mode;
     queue[num_cpu].routine = gbmv_kernel;