[PATCH 1/1] device-dax: Correct pgoff align in dax_set_mapping()

["Kun(llfl)" <llfl@linux.alibaba.com>]

pgoff should be aligned using ALIGN_DOWN() instead of ALIGN(). Otherwise,
vmf->address not aligned to fault_size will be aligned to the next
alignment, that can result in memory failure getting the wrong address.

Fixes: b9b5777f09be ("device-dax: use ALIGN() for determining pgoff")
Signed-off-by: Kun(llfl) <llfl@linux.alibaba.com>
Tested-by: JianXiong Zhao <zhaojianxiong.zjx@alibaba-inc.com>
---
 drivers/dax/device.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/dax/device.c b/drivers/dax/device.c
index 9c1a729cd77e..6d74e62bbee0 100644
--- a/drivers/dax/device.c
+++ b/drivers/dax/device.c
@@ -86,7 +86,7 @@ static void dax_set_mapping(struct vm_fault *vmf, pfn_t pfn,
 		nr_pages = 1;
 
 	pgoff = linear_page_index(vmf->vma,
-			ALIGN(vmf->address, fault_size));
+			ALIGN_DOWN(vmf->address, fault_size));
 
 	for (i = 0; i < nr_pages; i++) {
 		struct page *page = pfn_to_page(pfn_t_to_pfn(pfn) + i);
-- 
2.43.0