From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Huaisheng Ye Subject: [PATCH 1/5] libnvdimm, pmem: Allow a NULL-kaddr to ->direct_access() Date: Tue, 24 Jul 2018 16:45:06 +0800 Message-Id: <20180724084510.6104-2-yehs2007@zoho.com> In-Reply-To: <20180724084510.6104-1-yehs2007@zoho.com> References: <20180724084510.6104-1-yehs2007@zoho.com> Sender: linux-fsdevel-owner@vger.kernel.org List-Archive: List-Post: To: linux-nvdimm@lists.01.org, dan.j.williams@intel.com Cc: ross.zwisler@linux.intel.com, willy@infradead.org, vishal.l.verma@intel.com, dave.jiang@intel.com, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, viro@zeniv.linux.org.uk, martin.petersen@oracle.com, axboe@kernel.dk, gregkh@linuxfoundation.org, bart.vanassche@wdc.com, jack@suse.cz, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, linux-fsdevel@vger.kernel.org, chengnt@lenovo.com, Huaisheng Ye List-ID: From: Huaisheng Ye pmem_direct_access() needs to check the validity of second rank pointer kaddr for NULL assignment. If kaddr equals to NULL, it doesn't need to calculate the value. Signed-off-by: Huaisheng Ye --- drivers/nvdimm/pmem.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index 9d71492..b1d121a 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -232,7 +232,9 @@ __weak long __pmem_direct_access(struct pmem_device *pmem, pgoff_t pgoff, if (unlikely(is_bad_pmem(&pmem->bb, PFN_PHYS(pgoff) / 512, PFN_PHYS(nr_pages)))) return -EIO; - *kaddr = pmem->virt_addr + offset; + + if (kaddr) + *kaddr = pmem->virt_addr + offset; *pfn = phys_to_pfn_t(pmem->phys_addr + offset, pmem->pfn_flags); /* -- 1.8.3.1