================================================================== BUG: KCSAN: data-race in ext4_set_iomap / writeback_single_inode write to 0xffff8880bb43a340 of 8 bytes by task 10074 on cpu 0: writeback_single_inode+0x104/0x530 fs/fs-writeback.c:1562 sync_inode fs/fs-writeback.c:2602 [inline] sync_inode_metadata+0x52/0x70 fs/fs-writeback.c:2622 ext4_fsync_nojournal fs/ext4/fsync.c:92 [inline] ext4_sync_file+0x335/0x6e0 fs/ext4/fsync.c:170 vfs_fsync_range+0x107/0x120 fs/sync.c:200 generic_write_sync include/linux/fs.h:2730 [inline] ext4_buffered_write_iter+0x369/0x3b0 fs/ext4/file.c:277 ext4_file_write_iter+0x771/0x1010 include/linux/fs.h:774 call_write_iter include/linux/fs.h:1868 [inline] do_iter_readv_writev+0x32e/0x3d0 fs/read_write.c:713 do_iter_write+0x10e/0x470 fs/read_write.c:1018 vfs_iter_write+0x4c/0x70 fs/read_write.c:1059 iter_file_splice_write+0x41a/0x770 fs/splice.c:750 do_splice_from fs/splice.c:846 [inline] direct_splice_actor+0x95/0x160 fs/splice.c:1016 splice_direct_to_actor+0x365/0x660 fs/splice.c:971 do_splice_direct+0xf2/0x170 fs/splice.c:1059 do_sendfile+0x562/0xb10 fs/read_write.c:1540 __do_sys_sendfile64 fs/read_write.c:1601 [inline] __se_sys_sendfile64 fs/read_write.c:1587 [inline] __x64_sys_sendfile64+0xf2/0x130 fs/read_write.c:1587 do_syscall_64+0x51/0xb0 arch/x86/entry/common.c:384 entry_SYSCALL_64_after_hwframe+0x44/0xa9 read to 0xffff8880bb43a340 of 8 bytes by task 10070 on cpu 1: ext4_inode_datasync_dirty fs/ext4/inode.c:3306 [inline] ext4_set_iomap+0x138/0x3e0 fs/ext4/inode.c:3321 ext4_iomap_begin+0x5a0/0x5f0 fs/ext4/inode.c:3448 iomap_apply+0x8a/0x520 fs/iomap/apply.c:46 iomap_dio_rw+0x501/0x8c0 fs/iomap/direct-io.c:501 ext4_dio_write_iter fs/ext4/file.c:545 [inline] ext4_file_write_iter+0xda6/0x1010 fs/ext4/file.c:653 call_write_iter include/linux/fs.h:1868 [inline] do_iter_readv_writev+0x32e/0x3d0 fs/read_write.c:713 do_iter_write+0x10e/0x470 fs/read_write.c:1018 vfs_iter_write+0x4c/0x70 fs/read_write.c:1059 iter_file_splice_write+0x41a/0x770 fs/splice.c:750 do_splice_from fs/splice.c:846 [inline] direct_splice_actor+0x95/0x160 fs/splice.c:1016 splice_direct_to_actor+0x365/0x660 fs/splice.c:971 do_splice_direct+0xf2/0x170 fs/splice.c:1059 do_sendfile+0x562/0xb10 fs/read_write.c:1540 __do_sys_sendfile64 fs/read_write.c:1601 [inline] __se_sys_sendfile64 fs/read_write.c:1587 [inline] __x64_sys_sendfile64+0xf2/0x130 fs/read_write.c:1587 do_syscall_64+0x51/0xb0 arch/x86/entry/common.c:384 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 10070 Comm: syz-executor.1 Not tainted 5.8.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================