Hi Hongbo, kernel test robot noticed the following build warnings:
[auto build test WARNING on uml/next] [also build test WARNING on wireless-next/main wireless/main linus/master v6.9 next-20240513] [cannot apply to uml/fixes] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch#_base_tree_information] url: https://github.com/intel-lab-lkp/linux/commits/Hongbo-Li/hostfs-convert-hostfs-to-use-the-new-mount-api/20240513-204233 base: git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux next patch link: https://lore.kernel.org/r/20240513124141.3788846-1-lihongbo22%40huawei.com patch subject: [PATCH] hostfs: convert hostfs to use the new mount api config: um-allnoconfig (https://download.01.org/0day-ci/archive/20240513/202405132349.lj3qx7on-...@intel.com/config) compiler: clang version 17.0.6 (https://github.com/llvm/llvm-project 6009708b4367171ccdbf4b5905cb6a803753fe18) reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240513/202405132349.lj3qx7on-...@intel.com/reproduce) If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <l...@intel.com> | Closes: https://lore.kernel.org/oe-kbuild-all/202405132349.lj3qx7on-...@intel.com/ All warnings (new ones prefixed by >>): In file included from fs/hostfs/hostfs_kern.c:13: In file included from include/linux/pagemap.h:11: In file included from include/linux/highmem.h:12: In file included from include/linux/hardirq.h:11: In file included from arch/um/include/asm/hardirq.h:5: In file included from include/asm-generic/hardirq.h:17: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:13: In file included from arch/um/include/asm/io.h:24: include/asm-generic/io.h:547:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 547 | val = __raw_readb(PCI_IOBASE + addr); | ~~~~~~~~~~ ^ include/asm-generic/io.h:560:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 560 | val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr)); | ~~~~~~~~~~ ^ include/uapi/linux/byteorder/little_endian.h:37:51: note: expanded from macro '__le16_to_cpu' 37 | #define __le16_to_cpu(x) ((__force __u16)(__le16)(x)) | ^ In file included from fs/hostfs/hostfs_kern.c:13: In file included from include/linux/pagemap.h:11: In file included from include/linux/highmem.h:12: In file included from include/linux/hardirq.h:11: In file included from arch/um/include/asm/hardirq.h:5: In file included from include/asm-generic/hardirq.h:17: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:13: In file included from arch/um/include/asm/io.h:24: include/asm-generic/io.h:573:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 573 | val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr)); | ~~~~~~~~~~ ^ include/uapi/linux/byteorder/little_endian.h:35:51: note: expanded from macro '__le32_to_cpu' 35 | #define __le32_to_cpu(x) ((__force __u32)(__le32)(x)) | ^ In file included from fs/hostfs/hostfs_kern.c:13: In file included from include/linux/pagemap.h:11: In file included from include/linux/highmem.h:12: In file included from include/linux/hardirq.h:11: In file included from arch/um/include/asm/hardirq.h:5: In file included from include/asm-generic/hardirq.h:17: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:13: In file included from arch/um/include/asm/io.h:24: include/asm-generic/io.h:584:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 584 | __raw_writeb(value, PCI_IOBASE + addr); | ~~~~~~~~~~ ^ include/asm-generic/io.h:594:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 594 | __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr); | ~~~~~~~~~~ ^ include/asm-generic/io.h:604:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 604 | __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr); | ~~~~~~~~~~ ^ include/asm-generic/io.h:692:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 692 | readsb(PCI_IOBASE + addr, buffer, count); | ~~~~~~~~~~ ^ include/asm-generic/io.h:700:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 700 | readsw(PCI_IOBASE + addr, buffer, count); | ~~~~~~~~~~ ^ include/asm-generic/io.h:708:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 708 | readsl(PCI_IOBASE + addr, buffer, count); | ~~~~~~~~~~ ^ include/asm-generic/io.h:717:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 717 | writesb(PCI_IOBASE + addr, buffer, count); | ~~~~~~~~~~ ^ include/asm-generic/io.h:726:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 726 | writesw(PCI_IOBASE + addr, buffer, count); | ~~~~~~~~~~ ^ include/asm-generic/io.h:735:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 735 | writesl(PCI_IOBASE + addr, buffer, count); | ~~~~~~~~~~ ^ >> fs/hostfs/hostfs_kern.c:956:6: warning: variable 'host_root' is used >> uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized] 956 | if (fc->source == NULL) | ^~~~~~~~~~~~~~~~~~ fs/hostfs/hostfs_kern.c:960:44: note: uninitialized use occurs here 960 | kasprintf(GFP_KERNEL, "%s/%s", root_ino, host_root); | ^~~~~~~~~ fs/hostfs/hostfs_kern.c:956:2: note: remove the 'if' if its condition is always true 956 | if (fc->source == NULL) | ^~~~~~~~~~~~~~~~~~~~~~~ 957 | host_root = ""; fs/hostfs/hostfs_kern.c:942:17: note: initialize the variable 'host_root' to silence this warning 942 | char *host_root; | ^ | = NULL 13 warnings generated. vim +956 fs/hostfs/hostfs_kern.c 937 938 static int hostfs_fill_super(struct super_block *sb, struct fs_context *fc) 939 { 940 struct hostfs_fs_info *fsi = sb->s_fs_info; 941 struct inode *root_inode; 942 char *host_root; 943 int err; 944 945 sb->s_blocksize = 1024; 946 sb->s_blocksize_bits = 10; 947 sb->s_magic = HOSTFS_SUPER_MAGIC; 948 sb->s_op = &hostfs_sbops; 949 sb->s_d_op = &simple_dentry_operations; 950 sb->s_maxbytes = MAX_LFS_FILESIZE; 951 err = super_setup_bdi(sb); 952 if (err) 953 return err; 954 955 /* NULL is printed as '(null)' by printf(): avoid that. */ > 956 if (fc->source == NULL) 957 host_root = ""; 958 959 fsi->host_root_path = 960 kasprintf(GFP_KERNEL, "%s/%s", root_ino, host_root); 961 if (fsi->host_root_path == NULL) 962 return -ENOMEM; 963 964 root_inode = hostfs_iget(sb, fsi->host_root_path); 965 if (IS_ERR(root_inode)) 966 return PTR_ERR(root_inode); 967 968 if (S_ISLNK(root_inode->i_mode)) { 969 char *name; 970 971 iput(root_inode); 972 name = follow_link(fsi->host_root_path); 973 if (IS_ERR(name)) 974 return PTR_ERR(name); 975 976 root_inode = hostfs_iget(sb, name); 977 kfree(name); 978 if (IS_ERR(root_inode)) 979 return PTR_ERR(root_inode); 980 } 981 982 sb->s_root = d_make_root(root_inode); 983 if (sb->s_root == NULL) 984 return -ENOMEM; 985 986 return 0; 987 } 988 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki
