Re: deadlock caused by printk

Steven Rostedt
2011-03-25T18:42:00Z

On Fri, Mar 25, 2011 at 03:50:27PM +0100, Peter Zijlstra wrote:
> On Fri, 2011-03-25 at 22:30 +0800, Ming Lei wrote:
> >
> > But seems ftrace can't dump out the messages if system hangs,
>
> True.

Well, matters how the system hangs. Add in a nmi watchdog or other
watchdogs which can also trigger the ftrace_dump_on_oops.

>
> > so could
> > we introduce a smart and simple "printk" which can be used in any
> > contexts?
>
> I think you could use early_printk() for that, it doesn't bother with
> all the syslog muck.
>

Heh, I should have read the thread before replying to the first post ;)

-- Steve