================================================================== BUG: KCSAN: data-race in ext4_sync_file / writeback_single_inode write to 0xffff888125364bf0 of 8 bytes by task 17473 on cpu 0: writeback_single_inode+0x1fc/0x2f0 fs/fs-writeback.c:1562 sync_inode fs/fs-writeback.c:2602 [inline] sync_inode_metadata+0x75/0xa0 fs/fs-writeback.c:2622 ext4_fsync_nojournal fs/ext4/fsync.c:94 [inline] ext4_sync_file+0x47a/0x8b0 fs/ext4/fsync.c:172 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 0xffff888125364bf0 of 8 bytes by task 17580 on cpu 1: ext4_fsync_nojournal fs/ext4/fsync.c:89 [inline] ext4_sync_file+0x410/0x8b0 fs/ext4/fsync.c:172 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 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 17580 Comm: syz-executor.1 Not tainted 5.6.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================