On Sun, 10 Feb 2013 00:57:57 +0800 Haojian Zhuang <haojian.zhu...@linaro.org> wrote:
> do_initcalls() could call all driver initialization code in kernel_init > thread. It means that probe() function will be also called from that > time. After this, kernel could access console & release __init section > in the same thread. > > But if device probe fails and moves into deferred probe list, a new > thread is created to reinvoke probe. If the device is serial console, > kernel has to open console failure & release __init section before > reinvoking failure. Because there's no synchronization mechanism. > Now add wait event to synchronize after do_initcalls(). It sounds like this: static int __ref kernel_init(void *unused) { kernel_init_freeable(); /* need to finish all async __init code before freeing the memory */ async_synchronize_full(); is designed to prevent the problem you describe? > --- a/init/main.c > +++ b/init/main.c > @@ -786,6 +786,7 @@ static void __init do_basic_setup(void) > do_ctors(); > usermodehelper_enable(); > do_initcalls(); > + wait_for_device_probe(); > } Needs a nice comment here explaining what's going on. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/