================================================================== BUG: KCSAN: data-race in ext4_alloc_da_blocks / ext4_da_reserve_space read to 0xffff888128e99630 of 4 bytes by task 2832 on cpu 1: ext4_alloc_da_blocks+0x4b/0x180 fs/ext4/inode.c:3111 ext4_release_file+0x10d/0x210 fs/ext4/file.c:141 __fput+0x1e1/0x520 fs/file_table.c:280 ____fput+0x1f/0x30 fs/file_table.c:313 task_work_run+0xf6/0x130 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x2b4/0x2c0 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline] syscall_return_slowpath arch/x86/entry/common.c:278 [inline] do_syscall_64+0x384/0x3a0 arch/x86/entry/common.c:304 entry_SYSCALL_64_after_hwframe+0x44/0xa9 write to 0xffff888128e99630 of 4 bytes by task 2834 on cpu 0: ext4_da_reserve_space+0x13f/0x280 fs/ext4/inode.c:1470 ext4_insert_delayed_block fs/ext4/inode.c:1633 [inline] ext4_da_map_blocks fs/ext4/inode.c:1748 [inline] ext4_da_get_block_prep+0x87f/0xa60 fs/ext4/inode.c:1812 ext4_block_write_begin+0x33e/0xba0 fs/ext4/inode.c:1055 ext4_da_write_begin+0x208/0x840 fs/ext4/inode.c:2996 generic_perform_write+0x136/0x320 mm/filemap.c:3309 ext4_buffered_write_iter+0x143/0x290 fs/ext4/file.c:252 ext4_file_write_iter+0xf4/0xd40 fs/ext4/file.c:547 call_write_iter include/linux/fs.h:1902 [inline] new_sync_write+0x388/0x4a0 fs/read_write.c:483 __vfs_write+0xb1/0xc0 fs/read_write.c:496 vfs_write fs/read_write.c:558 [inline] vfs_write+0x18a/0x390 fs/read_write.c:542 ksys_write+0xd5/0x1b0 fs/read_write.c:611 __do_sys_write fs/read_write.c:623 [inline] __se_sys_write fs/read_write.c:620 [inline] __x64_sys_write+0x4c/0x60 fs/read_write.c:620 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 2834 Comm: syz-executor.3 Not tainted 5.5.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================