Re: [PATCH 5/6] mm/mremap: Use pmd/pud_poplulate to update page table entries
From: Linus Torvalds <torvalds@linux-foundation.org>
Date: 2021-06-10 18:17:12
On Thu, Jun 10, 2021 at 1:36 AM Aneesh Kumar K.V [off-list ref] wrote:
quoted hunk ↗ jump to hunk
@@ -306,8 +306,7 @@ static bool move_normal_pud(struct vm_area_struct *vma, unsigned long old_addr, VM_BUG_ON(!pud_none(*new_pud)); - /* Set the new pud */ - set_pud_at(mm, new_addr, new_pud, pud); + pud_populate(mm, new_pud, (pmd_t *)pud_page_vaddr(pud)); flush_tlb_range(vma, old_addr, old_addr + PUD_SIZE); if (new_ptl != old_ptl) spin_unlock(new_ptl);
That "(pmd_t *)pud_page_vaddr(pud)" looks a bit odd and doesn't match
the pattern.
Should we perhaps have a wrapper for it? Maybe called "pud_pgtable()",
the same way we have pmd_pgtable()?
And that wrapper would be good to have a comment or two about what it
actually is. The same way that pmd_pgtable() should but doesn't ;(
Linus