On Thu, Sep 23, 2021 at 04:17:38PM -0700, Andrew Morton wrote:
> On Thu, 23 Sep 2021 20:26:42 +0800 Qi Zheng <zhengqi.arch@xxxxxxxxxxxxx> wrote:
>
> > The paired pte_unmap() call is missing before the
> > dev_pagemap_mapping_shift() returns. So fix it.
> >
> > ...
> >
> > --- a/mm/memory-failure.c
> > +++ b/mm/memory-failure.c
> > @@ -306,6 +306,7 @@ static unsigned long dev_pagemap_mapping_shift(struct page *page,
> > struct vm_area_struct *vma)
> > {
> > unsigned long address = vma_address(page, vma);
> > + unsigned long ret = 0;
> > pgd_t *pgd;
> > p4d_t *p4d;
> > pud_t *pud;
> > @@ -330,10 +331,12 @@ static unsigned long dev_pagemap_mapping_shift(struct page *page,
> > return PMD_SHIFT;
> > pte = pte_offset_map(pmd, address);
> > if (!pte_present(*pte))
> > - return 0;
> > + goto unmap;
> > if (pte_devmap(*pte))
> > - return PAGE_SHIFT;
> > - return 0;
> > + ret = PAGE_SHIFT;
> > +unmap:
> > + pte_unmap(pte);
> > + return ret;
> > }
> >
>
> This is neater?
>
> +++ a/mm/memory-failure.c
> @@ -330,11 +330,8 @@ static unsigned long dev_pagemap_mapping
> if (pmd_devmap(*pmd))
> return PMD_SHIFT;
> pte = pte_offset_map(pmd, address);
> - if (!pte_present(*pte))
> - goto unmap;
> - if (pte_devmap(*pte))
> + if (pte_present(*pte) && pte_devmap(*pte))
> ret = PAGE_SHIFT;
> -unmap:
This neater one looks good to me.
Acked-by: Naoya Horiguchi <naoya.horiguchi@xxxxxxx>
