Hi Wei,
Thank you for looking at this patch.
> > +static void pmd_clear_level(struct mm_struct *mm, unsigned long addr,
> > + pmd_t *pmdp)
> > +{
> > + unsigned long i;
> > +
> > + for (i = 0; i < PTRS_PER_PMD; i++) {
> > + pmd_t old_pmd = *pmdp;
> > +
> > + if (pmd_user_accessible_page(old_pmd)) {
> > + page_table_check_clear(mm, addr, pmd_pfn(old_pmd),
> > + PMD_PAGE_SIZE >> PAGE_SHIFT);
> > + } else if (!pmd_bad(old_pmd) && !pmd_leaf(old_pmd)) {
> > + pte_t *ptep = pte_offset_map(&old_pmd, addr);
> > +
> > + pte_clear_level(mm, addr, ptep);
> > + pte_unmap(ptep);
> > + }
>
> You can call __page_table_check_pmd_clear(mm, addr, old_pmd, addr)
> instead to share the new code.
Yeap.
>
> >
> > + addr += PMD_PAGE_SIZE;
> > + pmdp++;
> > + }
> > +}
> > +
> > /*
> > * page is on free list, or is being allocated, verify that counters are zeroes
> > * crash if they are not.
> > @@ -186,6 +220,11 @@ void __page_table_check_pmd_clear(struct mm_struct *mm, unsigned long addr,
> > if (pmd_user_accessible_page(pmd)) {
> > page_table_check_clear(mm, addr, pmd_pfn(pmd),
> > PMD_PAGE_SIZE >> PAGE_SHIFT);
> > + } else if (!pmd_bad(pmd) && !pmd_leaf(pmd)) {
> > + pte_t *ptep = pte_offset_map(&pmd, addr);
> > +
> > + pte_clear_level(mm, addr, ptep);
> > + pte_unmap(ptep);
> > }
> > }
> > EXPORT_SYMBOL(__page_table_check_pmd_clear);
> > @@ -199,6 +238,10 @@ void __page_table_check_pud_clear(struct mm_struct *mm, unsigned long addr,
> > if (pud_user_accessible_page(pud)) {
> > page_table_check_clear(mm, addr, pud_pfn(pud),
> > PUD_PAGE_SIZE >> PAGE_SHIFT);
> > + } else if (!pud_bad(pud) && !pud_leaf(pud)) {
> > + pmd_t *pmdp = pmd_offset(&pud, addr);
> > +
> > + pmd_clear_level(mm, addr, pmdp);
> > }
> > }
> > EXPORT_SYMBOL(__page_table_check_pud_clear);
> > @@ -237,6 +280,11 @@ void __page_table_check_pmd_set(struct mm_struct *mm, unsigned long addr,
> > if (pmd_user_accessible_page(old_pmd)) {
> > page_table_check_clear(mm, addr, pmd_pfn(old_pmd),
> > PMD_PAGE_SIZE >> PAGE_SHIFT);
> > + } else if (!pmd_bad(old_pmd) && !pmd_leaf(old_pmd)) {
> > + pte_t *ptep = pte_offset_map(&old_pmd, addr);
> > +
> > + pte_clear_level(mm, addr, ptep);
> > + pte_unmap(ptep);
> > }
> >
>
> How about replacing the above code with
> __page_table_check_pmd_clear(mm, addr, old_pmd)?
OK
>
> > if (pmd_user_accessible_page(pmd)) {
> > @@ -259,6 +307,10 @@ void __page_table_check_pud_set(struct mm_struct *mm, unsigned long addr,
> > if (pud_user_accessible_page(old_pud)) {
> > page_table_check_clear(mm, addr, pud_pfn(old_pud),
> > PUD_PAGE_SIZE >> PAGE_SHIFT);
> > + } else if (!pud_bad(old_pud) && !pud_leaf(old_pud)) {
> > + pmd_t *pmdp = pmd_offset(&old_pud, addr);
> > +
> > + pmd_clear_level(mm, addr, pmdp);
> > }
>
> Replacing with __page_table_check_pud_clear(mm, addr, old_pud)?
OK
Good suggestions, I will simplify the code with your suggestions.
Pasha
