Re: [PATCH v4 1/2] drivers/s390/char: Add Ultravisor io device

[Steffen Eiden]

On 5/12/22 16:33, Claudio Imbrenda wrote:

[snip]

> > +/*
> > + * IOCTL entry point for the Ultravisor device.
> > + */
> > +static long uvio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
> > +{
> > +	void __user *argp = (void __user *)arg;
> > +	struct uvio_ioctl_cb *uv_ioctl;
> > +	long ret;
> > +
> > +	ret = -ENOMEM;
> > +	uv_ioctl = vzalloc(sizeof(*uv_ioctl));
> struct uvio_ioctl_cb is rather small, couldn't you just allocate it on
> the stack?
IIRC it was on stack in some previous version. We then had a discussion
earlier about this triggered by the inverse comment and decided to not 
use the stack.

[snip]