Re: lockdep warning: console vs. mem hotplug

From: Sebastian Ott
Date: Sat Mar 25 2017 - 06:59:58 EST


On Sat, 25 Mar 2017, Sergey Senozhatsky wrote:

> On (03/21/17 13:44), Sergey Senozhatsky wrote:
> [..]
> > so we probably can
> >
> >
> > 1) move pr_info() out of zone->lock in __offline_isolated_pages().
> > meh...
> >
> >
> > 2) switch to printk_deferred() in __offline_isolated_pages().
> > meh.. there might a bunch of other printks done from under zone->lock.
> >
> >
> > 3) move add_timer() out of sclp_con_lock console in sclp_console_write().
> > well, there can be other consoles that do something similar.
> >
> >
> > 4) ... something smart.
>
>
> Sebastian, does this change make lockdep happy?
>
> it removes console drivers from the __offline_isolated_pages(). not the
> best solution I can think of, but the simplest one.

It does. No complaint from lockdep.