================================================================== BUG: KCSAN: data-race in __add_to_page_cache_locked / ext4_writepages write to 0xffff88810f43c540 of 8 bytes by task 24682 on cpu 1: __add_to_page_cache_locked+0x2cc/0x6e0 mm/filemap.c:867 add_to_page_cache_lru+0xa0/0x1b0 mm/filemap.c:918 generic_file_buffered_read+0xc17/0x19e0 mm/filemap.c:2228 generic_file_read_iter+0x7d/0x3e0 mm/filemap.c:2326 ext4_file_read_iter+0x2d6/0x420 fs/ext4/file.c:74 call_read_iter include/linux/fs.h:1902 [inline] generic_file_splice_read+0x22a/0x310 fs/splice.c:312 do_splice_to fs/splice.c:870 [inline] splice_direct_to_actor+0x2a8/0x660 fs/splice.c:950 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 0xffff88810f43c540 of 8 bytes by task 24686 on cpu 0: ext4_writepages+0x145/0x1ef0 fs/ext4/inode.c:2650 do_writepages+0x7b/0x150 mm/page-writeback.c:2354 __filemap_fdatawrite_range+0x19b/0x1d0 mm/filemap.c:421 filemap_write_and_wait_range+0x8b/0x2a0 mm/filemap.c:654 iomap_dio_rw+0x399/0x8c0 fs/iomap/direct-io.c:474 ext4_dio_write_iter fs/ext4/file.c:545 [inline] ext4_file_write_iter+0xda4/0x1010 fs/ext4/file.c:653 call_write_iter include/linux/fs.h:1908 [inline] do_iter_readv_writev+0x321/0x3c0 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: 0 PID: 24686 Comm: syz-executor.2 Not tainted 5.8.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================