================================================================== BUG: KCSAN: data-race in wbc_detach_inode / wbc_detach_inode read to 0xffff8881259dda8c of 2 bytes by task 21334 on cpu 0: wbc_detach_inode+0x95/0x550 fs/fs-writeback.c:636 __filemap_fdatawrite_range+0x1d4/0x230 mm/filemap.c:421 filemap_write_and_wait_range mm/filemap.c:680 [inline] filemap_write_and_wait_range+0xb1/0x150 mm/filemap.c:674 generic_file_direct_write+0x27a/0x2e0 mm/filemap.c:3183 __generic_file_write_iter+0x17e/0x380 mm/filemap.c:3390 ext4_file_write_iter+0x1bd/0xa00 fs/ext4/file.c:268 call_write_iter include/linux/fs.h:1895 [inline] do_iter_readv_writev+0x487/0x5b0 fs/read_write.c:693 do_iter_write fs/read_write.c:970 [inline] do_iter_write+0x13b/0x3c0 fs/read_write.c:951 vfs_iter_write+0x5c/0x80 fs/read_write.c:983 iter_file_splice_write+0x4c0/0x7f0 fs/splice.c:746 do_splice_from fs/splice.c:848 [inline] direct_splice_actor+0xa0/0xc0 fs/splice.c:1020 splice_direct_to_actor+0x215/0x510 fs/splice.c:975 do_splice_direct+0x161/0x1e0 fs/splice.c:1063 do_sendfile+0x384/0x7f0 fs/read_write.c:1464 write to 0xffff8881259dda8c of 2 bytes by task 21336 on cpu 1: wbc_detach_inode+0x260/0x550 fs/fs-writeback.c:702 __filemap_fdatawrite_range+0x1d4/0x230 mm/filemap.c:421 file_write_and_wait_range+0xfd/0x160 mm/filemap.c:781 __generic_file_fsync+0x59/0x190 fs/libfs.c:1000 ext4_sync_file+0x48e/0xb00 fs/ext4/fsync.c:120 vfs_fsync_range+0x82/0x150 fs/sync.c:197 generic_write_sync include/linux/fs.h:2853 [inline] ext4_file_write_iter+0x45b/0xa00 fs/ext4/file.c:279 call_write_iter include/linux/fs.h:1895 [inline] do_iter_readv_writev+0x487/0x5b0 fs/read_write.c:693 do_iter_write fs/read_write.c:970 [inline] do_iter_write+0x13b/0x3c0 fs/read_write.c:951 vfs_iter_write+0x5c/0x80 fs/read_write.c:983 iter_file_splice_write+0x4c0/0x7f0 fs/splice.c:746 do_splice_from fs/splice.c:848 [inline] direct_splice_actor+0xa0/0xc0 fs/splice.c:1020 splice_direct_to_actor+0x215/0x510 fs/splice.c:975 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 21336 Comm: syz-executor.4 Not tainted 5.4.0-rc3+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================