[v3.13][v3.14][Regression] kthread: make kthread_create() killable

[Oleg Nesterov]

On 03/17, One Thousand Gnomes wrote:
>
> > and b) permits userspace to produce surprising results in the kernel,
> > which I suspect is what we're seeing here.
>
> There is enough information for kernel side code to decide whether a
> signal came from kernel or userspace.

Not really. SIGKILL can come without siginfo. Other signals too, but
SIGKILL especially.

> Then again - it's not clear that it
> should ever have to.

Yes, agreed.

Oleg.