From: Ralph Campbell <rcampbell@xxxxxxxxxx> Subject: mm/migrate: remove useless mask of start address Addresses passed to walk_page_range() callback functions are already page aligned and don't need to be masked with PAGE_MASK. Link: http://lkml.kernel.org/r/20200107211208.24595-2-rcampbell@xxxxxxxxxx Signed-off-by: Ralph Campbell <rcampbell@xxxxxxxxxx> Reviewed-by: Christoph Hellwig <hch@xxxxxx> Cc: Jerome Glisse <jglisse@xxxxxxxxxx> Cc: John Hubbard <jhubbard@xxxxxxxxxx> Cc: Jason Gunthorpe <jgg@xxxxxxxxxxxx> Cc: Bharata B Rao <bharata@xxxxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxxxx> Cc: Chris Down <chris@xxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/migrate.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/mm/migrate.c~mm-migrate-remove-useless-mask-of-start-address +++ a/mm/migrate.c @@ -2156,7 +2156,7 @@ static int migrate_vma_collect_hole(unsi struct migrate_vma *migrate = walk->private; unsigned long addr; - for (addr = start & PAGE_MASK; addr < end; addr += PAGE_SIZE) { + for (addr = start; addr < end; addr += PAGE_SIZE) { migrate->src[migrate->npages] = MIGRATE_PFN_MIGRATE; migrate->dst[migrate->npages] = 0; migrate->npages++; @@ -2173,7 +2173,7 @@ static int migrate_vma_collect_skip(unsi struct migrate_vma *migrate = walk->private; unsigned long addr; - for (addr = start & PAGE_MASK; addr < end; addr += PAGE_SIZE) { + for (addr = start; addr < end; addr += PAGE_SIZE) { migrate->dst[migrate->npages] = 0; migrate->src[migrate->npages++] = 0; } _