================================================================== BUG: KCSAN: data-race in wbc_detach_inode / wbc_detach_inode write to 0xffff88811f544cdc of 2 bytes by task 7446 on cpu 1: wbc_detach_inode+0x277/0x540 fs/fs-writeback.c:705 __filemap_fdatawrite_range+0x1c6/0x220 mm/filemap.c:422 file_write_and_wait_range+0xfb/0x160 mm/filemap.c:760 ext4_sync_file+0x26e/0x8b0 fs/ext4/fsync.c:153 vfs_fsync_range+0x7c/0x150 fs/sync.c:197 generic_write_sync include/linux/fs.h:2867 [inline] ext4_buffered_write_iter+0x211/0x280 fs/ext4/file.c:277 ext4_file_write_iter+0xf4/0xd30 fs/ext4/file.c:642 call_write_iter include/linux/fs.h:1901 [inline] do_iter_readv_writev+0x4a7/0x5d0 fs/read_write.c:693 do_iter_write fs/read_write.c:998 [inline] do_iter_write+0x137/0x3a0 fs/read_write.c:979 vfs_iter_write+0x56/0x80 fs/read_write.c:1039 iter_file_splice_write+0x530/0x830 fs/splice.c:760 do_splice_from fs/splice.c:863 [inline] direct_splice_actor+0x97/0xb0 fs/splice.c:1037 splice_direct_to_actor+0x22f/0x540 fs/splice.c:992 do_splice_direct+0x152/0x1d0 fs/splice.c:1080 do_sendfile+0x396/0x810 fs/read_write.c:1520 __do_sys_sendfile64 fs/read_write.c:1575 [inline] __se_sys_sendfile64 fs/read_write.c:1567 [inline] __x64_sys_sendfile64+0xb8/0x140 fs/read_write.c:1567 do_syscall_64+0xc7/0x390 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x44/0xa9 read to 0xffff88811f544cdc of 2 bytes by task 14375 on cpu 0: wbc_detach_inode+0x93/0x540 fs/fs-writeback.c:639 writeback_sb_inodes+0x4d2/0xa10 fs/fs-writeback.c:1718 __writeback_inodes_wb+0xe9/0x1b0 fs/fs-writeback.c:1785 wb_writeback+0x557/0x6a0 fs/fs-writeback.c:1894 wb_check_background_flush fs/fs-writeback.c:1962 [inline] wb_do_writeback fs/fs-writeback.c:2050 [inline] wb_workfn+0x66b/0x970 fs/fs-writeback.c:2078 process_one_work+0x424/0x930 kernel/workqueue.c:2264 worker_thread+0x9a/0x7e0 kernel/workqueue.c:2410 kthread+0x1cb/0x1f0 kernel/kthread.c:255 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 14375 Comm: kworker/u4:10 Not tainted 5.6.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: writeback wb_workfn (flush-8:0) ==================================================================