On Wed, 24 Feb 2016, Martin Schwidefsky wrote: > On Tue, 23 Feb 2016 22:33:45 +0300 > "Kirill A. Shutemov" <kirill@xxxxxxxxxxxxx> wrote: > > > On Tue, Feb 23, 2016 at 07:19:07PM +0100, Gerald Schaefer wrote: > > > I'll check with Martin, maybe it is actually trivial, then we can > > > do a quick test it to rule that one out. > > > > Oh. I found a bug in __split_huge_pmd_locked(). Although, not sure if it's > > _the_ bug. > > > > pmdp_invalidate() is called for the wrong address :-/ > > I guess that can be destructive on the architecture, right? > > > > Could you check this? > > > > diff --git a/mm/huge_memory.c b/mm/huge_memory.c > > index 1c317b85ea7d..4246bc70e55a 100644 > > --- a/mm/huge_memory.c > > +++ b/mm/huge_memory.c > > @@ -2865,7 +2865,7 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, > > pgtable = pgtable_trans_huge_withdraw(mm, pmd); > > pmd_populate(mm, &_pmd, pgtable); > > > > - for (i = 0; i < HPAGE_PMD_NR; i++, haddr += PAGE_SIZE) { > > + for (i = 0; i < HPAGE_PMD_NR; i++) { > > pte_t entry, *pte; > > /* > > * Note that NUMA hinting access restrictions are not > > @@ -2886,9 +2886,9 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, > > } > > if (dirty) > > SetPageDirty(page + i); > > - pte = pte_offset_map(&_pmd, haddr); > > + pte = pte_offset_map(&_pmd, haddr + i * PAGE_SIZE); > > BUG_ON(!pte_none(*pte)); > > - set_pte_at(mm, haddr, pte, entry); > > + set_pte_at(mm, haddr + i * PAGE_SIZE, pte, entry); > > atomic_inc(&page[i]._mapcount); > > pte_unmap(pte); > > } > > @@ -2938,7 +2938,7 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, > > pmd_populate(mm, pmd, pgtable); > > > > if (freeze) { > > - for (i = 0; i < HPAGE_PMD_NR; i++, haddr += PAGE_SIZE) { > > + for (i = 0; i < HPAGE_PMD_NR; i++) { > > page_remove_rmap(page + i, false); > > put_page(page + i); > > } > > Test is running and it looks good so far. For the final assessment I defer > to Gerald and Sebastian. > Yes, that one worked. My testsystem is doing make -j10 && make clean in a loop since 4 hours now. Thanks! Sebastian -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>