Re: [RFC PATCH v3 04/10] sched/core: Dont allow to use CPU marked as paravirt

[Shrikanth Hegde]

On 9/11/25 10:46 AM, K Prateek Nayak wrote:
> Hello Shrikanth,

Hi Prateek, Thanks for looking into this.

> On 9/10/2025 11:12 PM, Shrikanth Hegde wrote:
> > @@ -2462,8 +2462,13 @@ static inline bool is_cpu_allowed(struct task_struct *p, int cpu)
> >   		return cpu_online(cpu);
> >   
> >   	/* Non kernel threads are not allowed during either online or offline. */
> > -	if (!(p->flags & PF_KTHREAD))
> > -		return cpu_active(cpu);
> > +	if (!(p->flags & PF_KTHREAD)) {
> > +		/* A user thread shouldn't be allowed on a paravirt cpu */
> > +		if (is_cpu_paravirt(cpu))
> > +			return false;
> > +		else
>
> nit. redundant "else". I think this can be simplified as:

alright.
>      return !is_cpu_paravirt(cpu) && cpu_active(cpu);
>
> > +			return cpu_active(cpu);
> > +	}