On Fri 12-10-18 12:09:53, jglisse@xxxxxxxxxx wrote: > From: Jérôme Glisse <jglisse@xxxxxxxxxx> > > Inside set_pmd_migration_entry() we are holding page table locks and > thus we can not sleep so we can not call invalidate_range_start/end() > > So remove call to mmu_notifier_invalidate_range_start/end() and add > call to mmu_notifier_invalidate_range(). Note that we are already > calling mmu_notifier_invalidate_range_start/end() inside the function > calling set_pmd_migration_entry() (see try_to_unmap_one()). > > Signed-off-by: Jérôme Glisse <jglisse@xxxxxxxxxx> > Reported-by: Andrea Arcangeli <aarcange@xxxxxxxxxx> > Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> > Cc: Zi Yan <zi.yan@xxxxxxxxxxxxxx> > Cc: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> > Cc: "H. Peter Anvin" <hpa@xxxxxxxxx> > Cc: Anshuman Khandual <khandual@xxxxxxxxxxxxxxxxxx> > Cc: Dave Hansen <dave.hansen@xxxxxxxxx> > Cc: David Nellans <dnellans@xxxxxxxxxx> > Cc: Ingo Molnar <mingo@xxxxxxx> > Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx> > Cc: Minchan Kim <minchan@xxxxxxxxxx> > Cc: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx> > Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> > Cc: Vlastimil Babka <vbabka@xxxxxxx> > Cc: Michal Hocko <mhocko@xxxxxxxxxx> > Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx> Is this worth backporting to stable trees? The patch looks good to me Acked-by: Michal Hocko <mhocko@xxxxxxxx> > --- > mm/huge_memory.c | 7 +------ > 1 file changed, 1 insertion(+), 6 deletions(-) > > diff --git a/mm/huge_memory.c b/mm/huge_memory.c > index 533f9b00147d..93cb80fe12cb 100644 > --- a/mm/huge_memory.c > +++ b/mm/huge_memory.c > @@ -2885,9 +2885,6 @@ void set_pmd_migration_entry(struct page_vma_mapped_walk *pvmw, > if (!(pvmw->pmd && !pvmw->pte)) > return; > > - mmu_notifier_invalidate_range_start(mm, address, > - address + HPAGE_PMD_SIZE); > - > flush_cache_range(vma, address, address + HPAGE_PMD_SIZE); > pmdval = *pvmw->pmd; > pmdp_invalidate(vma, address, pvmw->pmd); > @@ -2898,11 +2895,9 @@ void set_pmd_migration_entry(struct page_vma_mapped_walk *pvmw, > if (pmd_soft_dirty(pmdval)) > pmdswp = pmd_swp_mksoft_dirty(pmdswp); > set_pmd_at(mm, address, pvmw->pmd, pmdswp); > + mmu_notifier_invalidate_range(mm, address, address + HPAGE_PMD_SIZE); > page_remove_rmap(page, true); > put_page(page); > - > - mmu_notifier_invalidate_range_end(mm, address, > - address + HPAGE_PMD_SIZE); > } > > void remove_migration_pmd(struct page_vma_mapped_walk *pvmw, struct page *new) > -- > 2.17.2 -- Michal Hocko SUSE Labs