------------[ cut here ]------------ ？

背景：

我在给335x打xenomia补丁，xenomai对于linux的补丁文件仅有linux3.2.21.但是板子提供的是linux3.2.0，于是打个小补丁将linux3.2.0升级到linux3.2.21，升级后再打xenomia补丁。

一些就绪后，编译内核生成uImage，通过uboot下载到板子上面

在内核启动后，可以看到不断的打印出启动信息，但是当打印到：

[ 0.000000] NR_IRQS:396
[ 0.000000] IRQ: Found an INTC at 0xfa200000 (revision 5.0) with 128 interrupts
[ 0.000000] Total of 128 interrupts on 1 active controller
[ 0.000000] OMAP clockevent source: GPTIMER2 at 24000000 Hz
[ 0.000000] OMAP clocksource: GPTIMER1 at 24000000 Hz
[ 0.000000] sched_clock: 32 bits at 24MHz, resolution 41ns, wraps every 178956ms
[ 0.000000] Interrupt pipeline (release #4)
[ 0.000000] ------------[ cut here ]------------

内核停止打印。

经测试， ------------[ cut here ]------------是由内核目录下的Panic.c (kernel)中的下面函数打印出来的：

static void warn_slowpath_common(const char *file, int line, void *caller,
unsigned taint, struct slowpath_args *args)
{
const char *board;

printk(KERN_WARNING "------------[ cut here ]------------\n");
printk(KERN_WARNING "WARNING: at %s:%d %pS()\n", file, line, caller);
board = dmi_get_system_info(DMI_PRODUCT_NAME);
if (board)
printk(KERN_WARNING "Hardware name: %s\n", board);

if (args)
vprintk(args->fmt, args->args);

print_modules();
dump_stack();
print_oops_end_marker();
add_taint(taint);
}

现在有个很奇怪的问题，通过上面的信息，看不出是哪里出错才打印出来。

于是我有添加了几个参考打印点:

static void warn_slowpath_common(const char *file, int line, void *caller,
unsigned taint, struct slowpath_args *args)
{
const char *board;

printk(KERN_WARNING "mark0\n");
printk(KERN_WARNING "------------[ cut here ]------------\n");
printk(KERN_WARNING "mark1\n");
printk(KERN_WARNING "WARNING: at %s:%d %pS()\n", file, line, caller);


board = dmi_get_system_info(DMI_PRODUCT_NAME);

此时有个奇怪的现象，内核在启动信息里只打印出了：

[ 0.000000] NR_IRQS:396
[ 0.000000] IRQ: Found an INTC at 0xfa200000 (revision 5.0) with 128 interrupts
[ 0.000000] Total of 128 interrupts on 1 active controller
[ 0.000000] OMAP clockevent source: GPTIMER2 at 24000000 Hz
[ 0.000000] OMAP clocksource: GPTIMER1 at 24000000 Hz
[ 0.000000] sched_clock: 32 bits at 24MHz, resolution 41ns, wraps every 178956ms
[ 0.000000] Interrupt pipeline (release #4)
[ 0.000000] mark0

然后停止。不在打印出后面其他要打印出来的信息。

然后，我屏蔽点本函数的打印信息，如下：

static void warn_slowpath_common(const char *file, int line, void *caller,
unsigned taint, struct slowpath_args *args)
{
const char *board;
/*
printk(KERN_WARNING "mark0\n");
printk(KERN_WARNING "------------[ cut here ]------------\n");
printk(KERN_WARNING "mark1\n");
printk(KERN_WARNING "WARNING: at %s:%d %pS()\n", file, line, caller);
*/

board = dmi_get_system_info(DMI_PRODUCT_NAME)

则可以通过内核启动信息看到：

0.000000] NR_IRQS:396
[ 0.000000] IRQ: Found an INTC at 0xfa200000 (revision 5.0) with 128 interrupts
[ 0.000000] Total of 128 interrupts on 1 active controller
[ 0.000000] OMAP clockevent source: GPTIMER2 at 24000000 Hz
[ 0.000000] OMAP clocksource: GPTIMER1 at 24000000 Hz
[ 0.000000] sched_clock: 32 bits at 24MHz, resolution 41ns, wraps every 178956ms
[ 0.000000] Interrupt pipeline (release #4)
[ 0.000000] 这里出现一句其他函数的 printk信息

然后内核启动停止。

请问这是什么原因。