Hi Wenzhuo, On 11/16/2016 3:28 AM, Lu, Wenzhuo wrote: > Hi Wei, > >> -----Original Message----- >> From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Wei Dai >> Sent: Wednesday, November 16, 2016 10:41 AM >> To: dev at dpdk.org; Burakov, Anatoly; david.marchand at 6wind.com; Dai, Wei >> Subject: [dpdk-dev] [PATCH v2] eal/linuxapp: fix return value check of >> mknod() >> >> In function pci_mknod_uio_dev() in lib/librte_eal/eal/eal_pci_uio.c, The >> return >> value of mknod() is ret, not f got by fopen(). >> So the value of ret should be checked for mknod(). >> >> Fixes: 67c536bdad93 ("pci: move uio mapping in a dedicated file") >> >> Signed-off-by: Wei Dai <wei.dai at intel.com> >> --- >> fix my local git setting and send same patch again to make merging easier >> >> lib/librte_eal/linuxapp/eal/eal_pci_uio.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/lib/librte_eal/linuxapp/eal/eal_pci_uio.c >> b/lib/librte_eal/linuxapp/eal/eal_pci_uio.c >> index 1786b75..3e4ffb5 100644 >> --- a/lib/librte_eal/linuxapp/eal/eal_pci_uio.c >> +++ b/lib/librte_eal/linuxapp/eal/eal_pci_uio.c >> @@ -133,7 +133,7 @@ pci_mknod_uio_dev(const char *sysfs_uio_path, >> unsigned uio_num) >> snprintf(filename, sizeof(filename), "/dev/uio%u", uio_num); >> dev = makedev(major, minor); >> ret = mknod(filename, S_IFCHR | S_IRUSR | S_IWUSR, dev); >> - if (f == NULL) { >> + if (ret != 0) { > I think checkpatch will suggest to just use if (ret)
Your are right, default checkpatch.pl complains about this usage (with --strict option), but: - According DPDK coding style this usage is preferred (although I personally prefer kernel one..) http://dpdk.org/doc/guides/contributing/coding_style.html#null-pointers " if (p == NULL) /* Good, compare pointer to NULL */ if (!p) /* Bad, using ! on pointer */ " - This warning disabled in dpdk scripts/checkpatches.sh by "--ignore COMPARISON_TO_NULL", so it shouldn't complain.