================================================================== BUG: KCSAN: data-race in ext4_ext_insert_extent / ext4_mark_iloc_dirty write to 0xffff88800d00015e of 2 bytes by task 19839 on cpu 0: ext4_ext_store_pblock fs/ext4/ext4_extents.h:256 [inline] ext4_ext_insert_extent+0x19e4/0x2b50 fs/ext4/extents.c:2116 ext4_ext_map_blocks+0x16a3/0x1fc0 fs/ext4/extents.c:4259 ext4_map_blocks+0x700/0xfc0 fs/ext4/inode.c:628 mpage_map_one_extent+0x10d/0x390 fs/ext4/inode.c:2387 mpage_map_and_submit_extent fs/ext4/inode.c:2440 [inline] ext4_writepages+0xa41/0x1e30 fs/ext4/inode.c:2792 do_writepages+0x7b/0x150 mm/page-writeback.c:2352 __filemap_fdatawrite_range+0x19d/0x1d0 mm/filemap.c:422 filemap_write_and_wait_range+0x8b/0x2a0 mm/filemap.c:655 __iomap_dio_rw+0x38c/0x9b0 fs/iomap/direct-io.c:489 iomap_dio_rw+0x30/0x70 fs/iomap/direct-io.c:605 ext4_dio_read_iter fs/ext4/file.c:77 [inline] ext4_file_read_iter+0x3bd/0x420 fs/ext4/file.c:129 call_read_iter include/linux/fs.h:1897 [inline] generic_file_splice_read+0x22a/0x310 fs/splice.c:311 do_splice_to fs/splice.c:788 [inline] splice_direct_to_actor+0x2aa/0x650 fs/splice.c:867 do_splice_direct+0xf5/0x170 fs/splice.c:976 do_sendfile+0x5db/0xca0 fs/read_write.c:1257 __do_sys_sendfile64 fs/read_write.c:1318 [inline] __se_sys_sendfile64 fs/read_write.c:1304 [inline] __x64_sys_sendfile64+0xf2/0x130 fs/read_write.c:1304 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 read to 0xffff88800d00015c of 4 bytes by task 19838 on cpu 1: ext4_do_update_inode fs/ext4/inode.c:5105 [inline] ext4_mark_iloc_dirty+0xd80/0x1650 fs/ext4/inode.c:5712 __ext4_mark_inode_dirty+0x450/0x610 fs/ext4/inode.c:5906 ext4_dirty_inode+0xa6/0xc0 fs/ext4/inode.c:5942 __mark_inode_dirty+0x74/0x740 fs/fs-writeback.c:2260 generic_update_time fs/inode.c:1764 [inline] update_time fs/inode.c:1777 [inline] touch_atime+0x1b1/0x2d0 fs/inode.c:1848 file_accessed include/linux/fs.h:2220 [inline] generic_file_buffered_read+0x1b30/0x23a0 mm/filemap.c:2476 generic_file_read_iter+0x80/0x3d0 mm/filemap.c:2553 ext4_file_read_iter+0x2d0/0x420 fs/ext4/file.c:74 call_read_iter include/linux/fs.h:1897 [inline] generic_file_splice_read+0x22a/0x310 fs/splice.c:311 do_splice_to fs/splice.c:788 [inline] splice_direct_to_actor+0x2aa/0x650 fs/splice.c:867 do_splice_direct+0xf5/0x170 fs/splice.c:976 do_sendfile+0x5db/0xca0 fs/read_write.c:1257 __do_sys_sendfile64 fs/read_write.c:1318 [inline] __se_sys_sendfile64 fs/read_write.c:1304 [inline] __x64_sys_sendfile64+0xf2/0x130 fs/read_write.c:1304 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 19838 Comm: syz-executor.2 Not tainted 5.10.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================