Hi Kuniyuki, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on linus/master] [also build test WARNING on v5.19-rc6 next-20220715] [cannot apply to jlayton/linux-next cel-2.6/for-next] [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/Kuniyuki-Iwashima/fs-lock-Don-t-allocate-file_lock-in-flock_make_lock/20220716-225519 base: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 9b59ec8d50a1f28747ceff9a4f39af5deba9540e config: mips-randconfig-r003-20220715 (https://download.01.org/0day-ci/archive/20220717/202207170400.ddCuQ7sy-lkp@xxxxxxxxx/config) compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project 07022e6cf9b5b3baa642be53d0b3c3f1c403dbfd) reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # install mips cross compiling tool for clang build # apt-get install binutils-mipsel-linux-gnu # https://github.com/intel-lab-lkp/linux/commit/7f68b5b24c3d8d371fb96ebe278dabb8c08bbf51 git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review Kuniyuki-Iwashima/fs-lock-Don-t-allocate-file_lock-in-flock_make_lock/20220716-225519 git checkout 7f68b5b24c3d8d371fb96ebe278dabb8c08bbf51 # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=mips SHELL=/bin/bash If you fix the issue, kindly add following tag where applicable Reported-by: kernel test robot <lkp@xxxxxxxxx> All warnings (new ones prefixed by >>): >> fs/locks.c:2103:6: warning: variable 'error' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized] if (!unlock && !(f.file->f_mode & (FMODE_READ|FMODE_WRITE))) ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ fs/locks.c:2139:9: note: uninitialized use occurs here return error; ^~~~~ fs/locks.c:2103:2: note: remove the 'if' if its condition is always false if (!unlock && !(f.file->f_mode & (FMODE_READ|FMODE_WRITE))) ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ fs/locks.c:2089:11: note: initialize the variable 'error' to silence this warning int error; ^ = 0 1 warning generated. vim +2103 fs/locks.c e55c34a66f87e7 Benjamin Coddington 2015-10-22 2068 ^1da177e4c3f41 Linus Torvalds 2005-04-16 2069 /** ^1da177e4c3f41 Linus Torvalds 2005-04-16 2070 * sys_flock: - flock() system call. ^1da177e4c3f41 Linus Torvalds 2005-04-16 2071 * @fd: the file descriptor to lock. ^1da177e4c3f41 Linus Torvalds 2005-04-16 2072 * @cmd: the type of lock to apply. ^1da177e4c3f41 Linus Torvalds 2005-04-16 2073 * ^1da177e4c3f41 Linus Torvalds 2005-04-16 2074 * Apply a %FL_FLOCK style lock to an open file descriptor. 80b79dd0e2f29f Mauro Carvalho Chehab 2017-05-27 2075 * The @cmd can be one of: ^1da177e4c3f41 Linus Torvalds 2005-04-16 2076 * 80b79dd0e2f29f Mauro Carvalho Chehab 2017-05-27 2077 * - %LOCK_SH -- a shared lock. 80b79dd0e2f29f Mauro Carvalho Chehab 2017-05-27 2078 * - %LOCK_EX -- an exclusive lock. 80b79dd0e2f29f Mauro Carvalho Chehab 2017-05-27 2079 * - %LOCK_UN -- remove an existing lock. 90f7d7a0d0d686 Jeff Layton 2021-09-10 2080 * - %LOCK_MAND -- a 'mandatory' flock. (DEPRECATED) ^1da177e4c3f41 Linus Torvalds 2005-04-16 2081 * 90f7d7a0d0d686 Jeff Layton 2021-09-10 2082 * %LOCK_MAND support has been removed from the kernel. ^1da177e4c3f41 Linus Torvalds 2005-04-16 2083 */ 002c8976ee5377 Heiko Carstens 2009-01-14 2084 SYSCALL_DEFINE2(flock, unsigned int, fd, unsigned int, cmd) ^1da177e4c3f41 Linus Torvalds 2005-04-16 2085 { 7f68b5b24c3d8d Kuniyuki Iwashima 2022-07-15 2086 int can_sleep, unlock, type; 7f68b5b24c3d8d Kuniyuki Iwashima 2022-07-15 2087 struct file_lock fl; 7f68b5b24c3d8d Kuniyuki Iwashima 2022-07-15 2088 struct fd f; ^1da177e4c3f41 Linus Torvalds 2005-04-16 2089 int error; ^1da177e4c3f41 Linus Torvalds 2005-04-16 2090 7f68b5b24c3d8d Kuniyuki Iwashima 2022-07-15 2091 type = flock_translate_cmd(cmd); 7f68b5b24c3d8d Kuniyuki Iwashima 2022-07-15 2092 if (type < 0) 7f68b5b24c3d8d Kuniyuki Iwashima 2022-07-15 2093 return type; 7f68b5b24c3d8d Kuniyuki Iwashima 2022-07-15 2094 7f68b5b24c3d8d Kuniyuki Iwashima 2022-07-15 2095 f = fdget(fd); 2903ff019b346a Al Viro 2012-08-28 2096 if (!f.file) 7f68b5b24c3d8d Kuniyuki Iwashima 2022-07-15 2097 return -EBADF; ^1da177e4c3f41 Linus Torvalds 2005-04-16 2098 ^1da177e4c3f41 Linus Torvalds 2005-04-16 2099 can_sleep = !(cmd & LOCK_NB); ^1da177e4c3f41 Linus Torvalds 2005-04-16 2100 cmd &= ~LOCK_NB; ^1da177e4c3f41 Linus Torvalds 2005-04-16 2101 unlock = (cmd == LOCK_UN); ^1da177e4c3f41 Linus Torvalds 2005-04-16 2102 90f7d7a0d0d686 Jeff Layton 2021-09-10 @2103 if (!unlock && !(f.file->f_mode & (FMODE_READ|FMODE_WRITE))) ^1da177e4c3f41 Linus Torvalds 2005-04-16 2104 goto out_putf; ^1da177e4c3f41 Linus Torvalds 2005-04-16 2105 90f7d7a0d0d686 Jeff Layton 2021-09-10 2106 /* 90f7d7a0d0d686 Jeff Layton 2021-09-10 2107 * LOCK_MAND locks were broken for a long time in that they never 90f7d7a0d0d686 Jeff Layton 2021-09-10 2108 * conflicted with one another and didn't prevent any sort of open, 90f7d7a0d0d686 Jeff Layton 2021-09-10 2109 * read or write activity. 90f7d7a0d0d686 Jeff Layton 2021-09-10 2110 * 90f7d7a0d0d686 Jeff Layton 2021-09-10 2111 * Just ignore these requests now, to preserve legacy behavior, but 90f7d7a0d0d686 Jeff Layton 2021-09-10 2112 * throw a warning to let people know that they don't actually work. 90f7d7a0d0d686 Jeff Layton 2021-09-10 2113 */ 90f7d7a0d0d686 Jeff Layton 2021-09-10 2114 if (cmd & LOCK_MAND) { 90f7d7a0d0d686 Jeff Layton 2021-09-10 2115 pr_warn_once("Attempt to set a LOCK_MAND lock via flock(2). This support has been removed and the request ignored.\n"); 90f7d7a0d0d686 Jeff Layton 2021-09-10 2116 error = 0; 90f7d7a0d0d686 Jeff Layton 2021-09-10 2117 goto out_putf; 90f7d7a0d0d686 Jeff Layton 2021-09-10 2118 } 90f7d7a0d0d686 Jeff Layton 2021-09-10 2119 7f68b5b24c3d8d Kuniyuki Iwashima 2022-07-15 2120 flock_make_lock(f.file, &fl, type); 6e129d00689c4d Jeff Layton 2014-09-04 2121 ^1da177e4c3f41 Linus Torvalds 2005-04-16 2122 if (can_sleep) 7f68b5b24c3d8d Kuniyuki Iwashima 2022-07-15 2123 fl.fl_flags |= FL_SLEEP; ^1da177e4c3f41 Linus Torvalds 2005-04-16 2124 7f68b5b24c3d8d Kuniyuki Iwashima 2022-07-15 2125 error = security_file_lock(f.file, fl.fl_type); ^1da177e4c3f41 Linus Torvalds 2005-04-16 2126 if (error) 7f68b5b24c3d8d Kuniyuki Iwashima 2022-07-15 2127 goto out_putf; ^1da177e4c3f41 Linus Torvalds 2005-04-16 2128 de2a4a501e716b Miklos Szeredi 2018-07-18 2129 if (f.file->f_op->flock) 2903ff019b346a Al Viro 2012-08-28 2130 error = f.file->f_op->flock(f.file, 7f68b5b24c3d8d Kuniyuki Iwashima 2022-07-15 2131 can_sleep ? F_SETLKW : F_SETLK, 7f68b5b24c3d8d Kuniyuki Iwashima 2022-07-15 2132 &fl); ^1da177e4c3f41 Linus Torvalds 2005-04-16 2133 else 7f68b5b24c3d8d Kuniyuki Iwashima 2022-07-15 2134 error = locks_lock_file_wait(f.file, &fl); ^1da177e4c3f41 Linus Torvalds 2005-04-16 2135 ^1da177e4c3f41 Linus Torvalds 2005-04-16 2136 out_putf: 2903ff019b346a Al Viro 2012-08-28 2137 fdput(f); 7f68b5b24c3d8d Kuniyuki Iwashima 2022-07-15 2138 ^1da177e4c3f41 Linus Torvalds 2005-04-16 2139 return error; ^1da177e4c3f41 Linus Torvalds 2005-04-16 2140 } ^1da177e4c3f41 Linus Torvalds 2005-04-16 2141 -- 0-DAY CI Kernel Test Service https://01.org/lkp
