From: Hugh Dickins hughd@google.com Subject: mm: page_vma_mapped_walk(): use page for pvmw->page

Patch series "mm: page_vma_mapped_walk() cleanup and THP fixes".

I've marked all of these for stable: many are merely cleanups, but I think they are much better before the main fix than after.

This patch (of 11):

page_vma_mapped_walk() cleanup: sometimes the local copy of pvwm->page was used, sometimes pvmw->page itself: use the local copy "page" throughout.

Link: https://lkml.kernel.org/r/589b358c-febc-c88e-d4c2-7834b37fa7bf@google.com Link: https://lkml.kernel.org/r/88e67645-f467-c279-bf5e-af4b5c6b13eb@google.com Signed-off-by: Hugh Dickins hughd@google.com Reviewed-by: Alistair Popple apopple@nvidia.com Acked-by: Kirill A. Shutemov kirill.shutemov@linux.intel.com Reviewed-by: Peter Xu peterx@redhat.com Cc: Yang Shi shy828301@gmail.com Cc: Wang Yugui wangyugui@e16-tech.com Cc: Matthew Wilcox willy@infradead.org Cc: Ralph Campbell rcampbell@nvidia.com Cc: Zi Yan ziy@nvidia.com Cc: Will Deacon will@kernel.org Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

mm/page_vma_mapped.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-)

--- a/mm/page_vma_mapped.c~mm-page_vma_mapped_walk-use-page-for-pvmw-page +++ a/mm/page_vma_mapped.c @@ -156,7 +156,7 @@ bool page_vma_mapped_walk(struct page_vm if (pvmw->pte) goto next_pte;

- if (unlikely(PageHuge(pvmw->page))) { + if (unlikely(PageHuge(page))) { /* when pud is not present, pte will be NULL */ pvmw->pte = huge_pte_offset(mm, pvmw->address, page_size(page)); if (!pvmw->pte) @@ -217,8 +217,7 @@ restart: * cannot return prematurely, while zap_huge_pmd() has * cleared *pmd but not decremented compound_mapcount(). */ - if ((pvmw->flags & PVMW_SYNC) && - PageTransCompound(pvmw->page)) { + if ((pvmw->flags & PVMW_SYNC) && PageTransCompound(page)) { spinlock_t *ptl = pmd_lock(mm, pvmw->pmd);

spin_unlock(ptl); @@ -234,9 +233,9 @@ restart: return true; next_pte: /* Seek to next pte only makes sense for THP */ - if (!PageTransHuge(pvmw->page) || PageHuge(pvmw->page)) + if (!PageTransHuge(page) || PageHuge(page)) return not_found(pvmw); - end = vma_address_end(pvmw->page, pvmw->vma); + end = vma_address_end(page, pvmw->vma); do { pvmw->address += PAGE_SIZE; if (pvmw->address >= end) _