Re: [PATCH v3 1/1] kthread: allocate kthread structure using kmalloc

[Oleg Nesterov]

On 10/26, Thomas Gleixner wrote:
>
> On Wed, 26 Oct 2016, Oleg Nesterov wrote:
> > +static inline void set_kthread_struct(void *kthread)
> > +{
> > +	/*
> > +	 * We abuse ->set_child_tid to avoid the new member and because it
> > +	 * can't be wrongly copied by copy_process(). We also rely on fact
> > +	 * that the caller can't exec, so PF_KTHREAD can't be cleared.
> > +	 */
> > +	current->set_child_tid = (__force void __user *)kthread;
>
> Can we pretty please avoid this type casting? We only have 5 places using
> set_child_tid. So we can really make it a proper union

Yes, I thought about anonymous union too, the only problem is that
it will need more comments ;)

And I agree with other nits, will redo/resend tomorrow.

Thanks!

Oleg.