Re: excessive kworker activity when idle. (was Re: vma corruption in today's -git)

Linus Torvalds
2011-03-31T15:26:35Z

On Thu, Mar 31, 2011 at 8:03 AM, Dave Jones <davej@redhat.com> wrote:
> On Thu, Mar 31, 2011 at 10:58:50AM -0400, Dave Jones wrote:
>
> bah I missed a level. which seems to be the smoking gun.
> something in the tty layer seems to have gone nuts.

Ahhah. That is indeed the smoking gun.

I bet it's an old problem where something causes some stupid tty
ping-pong behaviour, and now it has become a high-CPU thing triggered
by commit f23eb2b2b285 ("tty: stop using "delayed_work" in the tty
layer").

Before that commit, if the tty layer got somehow confused, it would
always delay for a timer tick in between doing nothing. Now it will go
pretty much full blast. Which explains your CPU being hot.

Linus