Re: [PATCH v2 6/7] vhost: Add kthread support in function vhost_worker_create

[Mike Christie]

On 10/3/24 8:58 PM, Cindy Lu wrote:
> +static struct vhost_worker *vhost_worker_create(struct vhost_dev *dev)
> +{
> +	if (enforce_inherit_owner)
> +		return vhost_worker_create_task(dev);
> +	else
> +		return vhost_worker_create_kthread(dev);
> +}

The reason we are in this whole mess is because for vhost-scsi
we wanted to create multiple worker threads as the single thread
became a bottleneck. We couldn't use kthreads because they were
not accounted for under thread that created it and we could
exceed the NPROC_LIMIT.

So with the above code, we could hit that problem again if userspace
did the VHOST_NEW_WORKER ioctl and enforce_inherit_owner=false.

You would want a check for enforce_inherit_owner in vhost_worker_ioctl.