Commit b5b10ca931ab upstream. QUEUE_FLAG_DAX is an indication that a given block device supports filesystem DAX and should not be set for PMEM namespaces which are in "raw" mode. These namespaces lack struct page and are prevented from participating in filesystem DAX as of commit 569d0365f571 "dax: require 'struct page' by default for filesystem dax". Signed-off-by: Ross Zwisler <ross.zwisler@xxxxxxxxxxxxxxx> Suggested-by: Mike Snitzer <snitzer@xxxxxxxxxx> --- drivers/nvdimm/pmem.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index 9d714926ecf5..c329fc7a86dc 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -388,7 +388,8 @@ static int pmem_attach_disk(struct device *dev, blk_queue_logical_block_size(q, pmem_sector_size(ndns)); blk_queue_max_hw_sectors(q, UINT_MAX); blk_queue_flag_set(QUEUE_FLAG_NONROT, q); - blk_queue_flag_set(QUEUE_FLAG_DAX, q); + if (pmem->pfn_flags & PFN_MAP) + blk_queue_flag_set(QUEUE_FLAG_DAX, q); q->queuedata = pmem; disk = alloc_disk_node(0, nid); -- 2.14.4