On Fri, Jun 27, 2025 at 10:49:34AM +0300, Adrian Hunter wrote:
> On 09/06/2025 22:13, Kirill A. Shutemov wrote:
> > +static void tdx_pamt_put(struct page *page, enum pg_level level)
> > +{
> > + unsigned long hpa = page_to_phys(page);
> > + atomic_t *pamt_refcount;
> > + LIST_HEAD(pamt_pages);
> > + u64 err;
> > +
> > + if (!tdx_supports_dynamic_pamt(&tdx_sysinfo))
> > + return;
> > +
> > + if (level != PG_LEVEL_4K)
> > + return;
> > +
> > + hpa = ALIGN_DOWN(hpa, PMD_SIZE);
> > +
> > + pamt_refcount = tdx_get_pamt_refcount(hpa);
> > + if (!atomic_dec_and_test(pamt_refcount))
> > + return;
> > +
> > + scoped_guard(spinlock, &pamt_lock) {
> > + /* Lost race against tdx_pamt_add()? */
> > + if (atomic_read(pamt_refcount) != 0)
> > + return;
> > +
> > + err = tdh_phymem_pamt_remove(hpa | TDX_PS_2M, &pamt_pages);
> > +
> > + if (err) {
> > + atomic_inc(pamt_refcount);
> > + pr_err("TDH_PHYMEM_PAMT_REMOVE failed: %#llx\n", err);
> > + return;
> > + }
> > + }
> > +
>
> Won't any pages that have been used need to be cleared
> before being freed.
Good point. I missed that.
--
Kiryl Shutsemau / Kirill A. Shutemov
