diff --git a/mk/qemu.mk b/mk/qemu.mk
index 62db45e8e..b9740e619 100644
--- a/mk/qemu.mk
+++ b/mk/qemu.mk
@@ -272,6 +272,9 @@ endif
 
 ifeq ($(gdb),yes)
 	QEMUFLAGS+=-d cpu_reset -s -S
+else ifeq ($(gdb),nonblock)
+	# Allow attaching gdb, but don't block for it
+	QEMUFLAGS+=-d cpu_reset -s
 endif
 
 ifeq ($(UNAME),Linux)