Re: [PATCH v3 29/30] luo: allow preserving memfd

[Pasha Tatashin]

> +static int memfd_luo_preserve_folios(struct memfd_luo_preserved_folio *pfolios,
> +                                    struct folio **folios,
> +                                    unsigned int nr_folios)
> +{
> +       unsigned int i;

Should be 'long i'

Otherwise in err_unpreserve we get into an infinite loop. Thank you
Josh Hilke for noticing this.

Pasha

> +       int err;
> +
> +       for (i = 0; i < nr_folios; i++) {
> +               struct memfd_luo_preserved_folio *pfolio = &pfolios[i];
> +               struct folio *folio = folios[i];
> +               unsigned int flags = 0;
> +               unsigned long pfn;
> +
> +               err = kho_preserve_folio(folio);
> +               if (err)
> +                       goto err_unpreserve;
> +
> +               pfn = folio_pfn(folio);
> +               if (folio_test_dirty(folio))
> +                       flags |= PRESERVED_FLAG_DIRTY;
> +               if (folio_test_uptodate(folio))
> +                       flags |= PRESERVED_FLAG_UPTODATE;
> +
> +               pfolio->foliodesc = PRESERVED_FOLIO_MKDESC(pfn, flags);
> +               pfolio->index = folio->index;
> +       }
> +
> +       return 0;
> +
> +err_unpreserve:
> +       i--;
> +       for (; i >= 0; i--)
> +               WARN_ON_ONCE(kho_unpreserve_folio(folios[i]));
> +       return err;
> +}
> +