Re: [PATCH v2 1/1] KVM: s390: pv: fix race when making a page secure

[David Hildenbrand]

> +int make_hva_secure(struct mm_struct *mm, unsigned long hva, struct uv_cb_header *uvcb)
> +{
> +	struct folio *folio;
> +	spinlock_t *ptelock;
> +	pte_t *ptep;
> +	int rc;
> +
> +	ptep = get_locked_valid_pte(mm, hva, &ptelock);
> +	if (!ptep)
> +		return -ENXIO;

You very likely need a pte_write() check we had there before, as you 
might effectively modify page content by clearing the page.

--
Cheers,

David / dhildenb