Re: [PATCH] cpu/hotplug: handle unbalanced hotplug enable/disable

From: Thomas Gleixner
Date: Mon Apr 25 2016 - 04:24:48 EST


On Fri, 22 Apr 2016, Lianwei Wang wrote:
> Any way is Ok for debugging purpose. But think the kernel run on a
> customer machine, such as PC, Mobile phone or other devices. How we
> let the customer debug it but not recover it smartly?

There is nothing smart here. Restoring the count is a bandaid and has nothing
to do with recovery. If that WARN_ON triggers then other stuff is going to be
more fundamentally wrong so restoring the count is the least of our worries.

> Anyway, from a product perspective way, if we don't want to restore
> the unbalanced counter to 0, then maybe a BUG_ON is more reasonable
> than WARN_ON.

Not at all. BUG_ON is the last resort if we have no other way to handle an
issue.

Thanks,

tglx