Add boot message about how to exit qemu

Makefile

@@ -48,6 +48,9 @@ CFLAGS += -I./kern/libkern
 
 all: kern/kernel.elf
 
+quickstart:
+	make get_toolchain && bear -- make -j$(nproc) && make qemu
+
 KERNEL_OBJ := \
 	kern/entry.o \
 	kern/start.o \
@@ -135,4 +138,4 @@ info:
 
 -include *.d
 
-.PHONY: all qemu info
+.PHONY: all qemu info quickstart

kern/start.c

@@ -57,6 +57,7 @@ void start() {
         else
             PANIC("Some cores seem to have been enumerated incorrectly!\n");
 
+        kprintf("To exit qemu, press CTRL+a followed by x\n");
         spin_unlock(&sl);
     }