diff options
| -rw-r--r-- | include/linux/mm.h | 9 | ||||
| -rw-r--r-- | mm/page_alloc.c | 8 |
2 files changed, 13 insertions, 4 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h index de32c0383387..93a46ff33dc2 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1594,8 +1594,13 @@ static inline bool page_needs_cow_for_dma(struct vm_area_struct *vma, #ifdef CONFIG_MIGRATION static inline bool is_pinnable_page(struct page *page) { - return !(is_zone_movable_page(page) || is_migrate_cma_page(page)) || - is_zero_pfn(page_to_pfn(page)); +#ifdef CONFIG_CMA + int mt = get_pageblock_migratetype(page); + + if (mt == MIGRATE_CMA || mt == MIGRATE_ISOLATE) + return false; +#endif + return !(is_zone_movable_page(page) || is_zero_pfn(page_to_pfn(page))); } #else static inline bool is_pinnable_page(struct page *page) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 6f6e4649ac21..56b3a5d67325 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -482,8 +482,12 @@ unsigned long __get_pfnblock_flags_mask(const struct page *page, bitidx = pfn_to_bitidx(page, pfn); word_bitidx = bitidx / BITS_PER_LONG; bitidx &= (BITS_PER_LONG-1); - - word = bitmap[word_bitidx]; + /* + * This races, without locks, with set_pfnblock_flags_mask(). Ensure + * a consistent read of the memory array, so that results, even though + * racy, are not corrupted. + */ + word = READ_ONCE(bitmap[word_bitidx]); return (word >> bitidx) & mask; } |