tree: https://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4.git dev head: ab7b179af3f98772f2433ddc4ace6b7924a4e862 commit: 090f311f4264ec136e6dcd19804eb9665230e67f [11/44] ext4: fast commit recovery path config: x86_64-randconfig-a004-20201009 (attached as .config) compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project 4cfc4025cc1433ca5ef1c526053fc9c4bfe64109) 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 x86_64 cross compiling tool for clang build # apt-get install binutils-x86-64-linux-gnu # https://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4.git/commit/?id=090f311f4264ec136e6dcd19804eb9665230e67f git remote add ext4 https://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4.git git fetch --no-tags ext4 dev git checkout 090f311f4264ec136e6dcd19804eb9665230e67f # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot All warnings (new ones prefixed by >>): >> fs/ext4/mballoc.c:5221:6: warning: no previous prototype for function 'ext4_free_blocks_simple' [-Wmissing-prototypes] void ext4_free_blocks_simple(struct inode *inode, ext4_fsblk_t block, ^ fs/ext4/mballoc.c:5221:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void ext4_free_blocks_simple(struct inode *inode, ext4_fsblk_t block, ^ static 1 warning generated. -- fs/ext4/fast_commit.c:1091:6: warning: variable 'start_time' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized] if (!test_opt2(sb, JOURNAL_FAST_COMMIT) || ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ fs/ext4/fast_commit.c:1147:51: note: uninitialized use occurs here commit_time = ktime_to_ns(ktime_sub(ktime_get(), start_time)); ^~~~~~~~~~ include/linux/ktime.h:47:39: note: expanded from macro 'ktime_sub' #define ktime_sub(lhs, rhs) ((lhs) - (rhs)) ^~~ fs/ext4/fast_commit.c:1091:2: note: remove the 'if' if its condition is always false if (!test_opt2(sb, JOURNAL_FAST_COMMIT) || ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ fs/ext4/fast_commit.c:1091:6: warning: variable 'start_time' is used uninitialized whenever '||' condition is true [-Wsometimes-uninitialized] if (!test_opt2(sb, JOURNAL_FAST_COMMIT) || ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ fs/ext4/fast_commit.c:1147:51: note: uninitialized use occurs here commit_time = ktime_to_ns(ktime_sub(ktime_get(), start_time)); ^~~~~~~~~~ include/linux/ktime.h:47:39: note: expanded from macro 'ktime_sub' #define ktime_sub(lhs, rhs) ((lhs) - (rhs)) ^~~ fs/ext4/fast_commit.c:1091:6: note: remove the '||' if its condition is always false if (!test_opt2(sb, JOURNAL_FAST_COMMIT) || ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ fs/ext4/fast_commit.c:1087:20: note: initialize the variable 'start_time' to silence this warning ktime_t start_time, commit_time; ^ = 0 >> fs/ext4/fast_commit.c:1787:6: warning: no previous prototype for function 'ext4_fc_set_bitmaps_and_counters' [-Wmissing-prototypes] void ext4_fc_set_bitmaps_and_counters(struct super_block *sb) ^ fs/ext4/fast_commit.c:1787:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void ext4_fc_set_bitmaps_and_counters(struct super_block *sb) ^ static 3 warnings generated. vim +/ext4_free_blocks_simple +5221 fs/ext4/mballoc.c 5220 > 5221 void ext4_free_blocks_simple(struct inode *inode, ext4_fsblk_t block, 5222 unsigned long count) 5223 { 5224 struct buffer_head *bitmap_bh; 5225 struct super_block *sb = inode->i_sb; 5226 struct ext4_group_desc *gdp; 5227 struct buffer_head *gdp_bh; 5228 ext4_group_t group; 5229 ext4_grpblk_t blkoff; 5230 int already_freed = 0, err, i; 5231 5232 ext4_get_group_no_and_offset(sb, block, &group, &blkoff); 5233 bitmap_bh = ext4_read_block_bitmap(sb, group); 5234 if (IS_ERR(bitmap_bh)) { 5235 err = PTR_ERR(bitmap_bh); 5236 pr_warn("Failed to read block bitmap\n"); 5237 return; 5238 } 5239 gdp = ext4_get_group_desc(sb, group, &gdp_bh); 5240 if (!gdp) 5241 return; 5242 5243 for (i = 0; i < count; i++) { 5244 if (!mb_test_bit(blkoff + i, bitmap_bh->b_data)) 5245 already_freed++; 5246 } 5247 mb_clear_bits(bitmap_bh->b_data, blkoff, count); 5248 err = ext4_handle_dirty_metadata(NULL, NULL, bitmap_bh); 5249 if (err) 5250 return; 5251 ext4_free_group_clusters_set( 5252 sb, gdp, ext4_free_group_clusters(sb, gdp) + 5253 count - already_freed); 5254 ext4_block_bitmap_csum_set(sb, group, gdp, bitmap_bh); 5255 ext4_group_desc_csum_set(sb, group, gdp); 5256 ext4_handle_dirty_metadata(NULL, NULL, gdp_bh); 5257 sync_dirty_buffer(bitmap_bh); 5258 sync_dirty_buffer(gdp_bh); 5259 brelse(bitmap_bh); 5260 } 5261 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org