Some drivers do depend on page mappings to be page aligned. Swiotlb already enforces such alignment for mappings greater than page, extend that to page-sized mappings as well.
Without this fix, nvme hits BUG() in nvme_setup_prps(), because that routine assumes page-aligned mappings. Signed-off-by: Nikita Yushchenko <[email protected]> --- lib/swiotlb.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/lib/swiotlb.c b/lib/swiotlb.c index 975b8fc..a8d74a7 100644 --- a/lib/swiotlb.c +++ b/lib/swiotlb.c @@ -483,11 +483,11 @@ phys_addr_t swiotlb_tbl_map_single(struct device *hwdev, : 1UL << (BITS_PER_LONG - IO_TLB_SHIFT); /* - * For mappings greater than a page, we limit the stride (and - * hence alignment) to a page size. + * For mappings greater than or equal to a page, we limit the stride + * (and hence alignment) to a page size. */ nslots = ALIGN(size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT; - if (size > PAGE_SIZE) + if (size >= PAGE_SIZE) stride = (1 << (PAGE_SHIFT - IO_TLB_SHIFT)); else stride = 1; -- 2.1.4
