================================================================== BUG: KCSAN: data-race in __ext4_new_inode / find_next_zero_bit write to 0xffff888104fb12c0 of 8 bytes by task 4891 on cpu 1: 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+0xf1e/0x2f10 fs/ext4/ialloc.c:1093 ext4_symlink+0x2c3/0x700 fs/ext4/namei.c:3347 vfs_symlink+0xbe/0x170 fs/namei.c:4178 do_symlinkat+0xeb/0x280 fs/namei.c:4208 __do_sys_symlink fs/namei.c:4229 [inline] __se_sys_symlink fs/namei.c:4227 [inline] __x64_sys_symlink+0x32/0x40 fs/namei.c:4227 do_syscall_64+0x34/0x50 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffff888104fb12c0 of 8 bytes by task 1762 on cpu 0: _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+0xc6a/0x2f10 fs/ext4/ialloc.c:1063 ext4_mkdir+0x28a/0x760 fs/ext4/namei.c:2804 vfs_mkdir+0x135/0x1f0 fs/namei.c:3819 do_mkdirat+0x11d/0x200 fs/namei.c:3844 __do_sys_mkdir fs/namei.c:3862 [inline] __se_sys_mkdir fs/namei.c:3860 [inline] __x64_sys_mkdir+0x32/0x40 fs/namei.c:3860 do_syscall_64+0x34/0x50 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 1762 Comm: syz-executor.2 Not tainted 5.12.0-rc8-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================