================================================================== BUG: KCSAN: data-race in ext4_alloc_da_blocks / ext4_da_reserve_space write to 0xffff888106a0d9d8 of 4 bytes by task 2001 on cpu 0: ext4_da_reserve_space+0x147/0x200 fs/ext4/inode.c:1491 ext4_insert_delayed_block fs/ext4/inode.c:1656 [inline] ext4_da_map_blocks fs/ext4/inode.c:1770 [inline] ext4_da_get_block_prep+0x512/0x9b0 fs/ext4/inode.c:1834 __block_write_begin_int+0x4a2/0x1060 fs/buffer.c:2006 __block_write_begin+0x2b/0x40 fs/buffer.c:2056 ext4_da_write_begin+0x4c8/0x820 fs/ext4/inode.c:3018 generic_perform_write+0x196/0x3c0 mm/filemap.c:3656 ext4_buffered_write_iter+0x2f2/0x3f0 fs/ext4/file.c:269 ext4_file_write_iter+0x2e7/0x11d0 fs/ext4/file.c:519 call_write_iter include/linux/fs.h:2114 [inline] aio_write+0x287/0x360 fs/aio.c:1578 __io_submit_one fs/aio.c:1837 [inline] io_submit_one+0x82f/0x1350 fs/aio.c:1880 __do_sys_io_submit fs/aio.c:1939 [inline] __se_sys_io_submit+0xf5/0x260 fs/aio.c:1909 __x64_sys_io_submit+0x3f/0x50 fs/aio.c:1909 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffff888106a0d9d8 of 4 bytes by task 2004 on cpu 1: ext4_alloc_da_blocks+0x1a/0xd0 fs/ext4/inode.c:3130 ext4_release_file+0x5b/0x1d0 fs/ext4/file.c:141 __fput+0x25b/0x4e0 fs/file_table.c:280 ____fput+0x11/0x20 fs/file_table.c:313 task_work_run+0xae/0x130 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:175 [inline] exit_to_user_mode_prepare+0x156/0x190 kernel/entry/common.c:209 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:302 do_syscall_64+0x49/0x90 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae value changed: 0x00000c94 -> 0x00000c97 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 2004 Comm: syz-executor.1 Not tainted 5.14.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================