================================================================== BUG: KCSAN: data-race in __ext4_new_inode / find_next_zero_bit write to 0xffff8881050812f8 of 8 bytes by task 1783 on cpu 0: instrument_write include/linux/instrumented.h:42 [inline] __instrument_read_write_bitop include/asm-generic/bitops/instrumented-non-atomic.h:79 [inline] __test_and_set_bit include/asm-generic/bitops/instrumented-non-atomic.h:95 [inline] __test_and_set_bit_le include/asm-generic/bitops/le.h:90 [inline] __ext4_new_inode+0xf3e/0x2f70 fs/ext4/ialloc.c:1093 ext4_mkdir+0x28a/0x760 fs/ext4/namei.c:2920 vfs_mkdir+0x2a4/0x370 fs/namei.c:3813 do_mkdirat+0x11d/0x200 fs/namei.c:3838 __do_sys_mkdir fs/namei.c:3856 [inline] __se_sys_mkdir fs/namei.c:3854 [inline] __x64_sys_mkdir+0x32/0x40 fs/namei.c:3854 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffff8881050812f8 of 8 bytes by task 8305 on cpu 1: _find_next_bit lib/find_bit.c:41 [inline] find_next_zero_bit+0x3a/0xf0 lib/find_bit.c:89 find_next_zero_bit_le include/asm-generic/bitops/le.h:15 [inline] find_inode_bit+0x30c/0x3a0 fs/ext4/ialloc.c:722 __ext4_new_inode+0xc7a/0x2f70 fs/ext4/ialloc.c:1063 ext4_symlink+0x2c3/0x700 fs/ext4/namei.c:3464 vfs_symlink+0x23a/0x300 fs/namei.c:4172 do_symlinkat+0xeb/0x280 fs/namei.c:4202 __do_sys_symlink fs/namei.c:4223 [inline] __se_sys_symlink fs/namei.c:4221 [inline] __x64_sys_symlink+0x32/0x40 fs/namei.c:4221 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 8305 Comm: syz-executor.3 Not tainted 5.12.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================