From: Huaisheng Ye <yehs1@xxxxxxxxxx> Some functions within fs/dax don't need to get gfn from direct_access. Assigning NULL to gfn of dax_direct_access is more intuitive and simple than offering a useless local variable. So direct_access needs to check validity of the pointer pfn For NULL assignment. Signed-off-by: Huaisheng Ye <yehs1@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 9d71492..018f990 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -233,7 +233,8 @@ __weak long __pmem_direct_access(struct pmem_device *pmem, pgoff_t pgoff, PFN_PHYS(nr_pages)))) return -EIO; *kaddr = pmem->virt_addr + offset; - *pfn = phys_to_pfn_t(pmem->phys_addr + offset, pmem->pfn_flags); + if (pfn) + *pfn = phys_to_pfn_t(pmem->phys_addr + offset, pmem->pfn_flags); /* * If badblocks are present, limit known good range to the -- 1.8.3.1