syzbot

loop2: detected capacity change from 0 to 1024
EXT4-fs: Ignoring removed orlov option
EXT4-fs (loop2): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: writeback.
==================================================================
BUG: KCSAN: data-race in __xa_clear_mark / file_write_and_wait_range

write to 0xffff88812f452b24 of 4 bytes by interrupt on cpu 0:
 xa_mark_clear lib/xarray.c:77 [inline]
 xas_clear_mark lib/xarray.c:925 [inline]
 __xa_clear_mark+0x1cc/0x1f0 lib/xarray.c:1957
 __folio_end_writeback+0x187/0x490 mm/page-writeback.c:3093
 folio_end_writeback+0x74/0x1f0 mm/filemap.c:1624
 ext4_finish_bio+0x476/0x8e0 fs/ext4/page-io.c:144
 ext4_end_bio+0x18c/0x2c0
 bio_endio+0x369/0x410 block/bio.c:1645
 blk_update_request+0x368/0x860 block/blk-mq.c:981
 blk_mq_end_request+0x26/0x50 block/blk-mq.c:1143
 lo_complete_rq+0xce/0x180 drivers/block/loop.c:386
 blk_complete_reqs block/blk-mq.c:1218 [inline]
 blk_done_softirq+0x74/0xb0 block/blk-mq.c:1223
 handle_softirqs+0xbf/0x280 kernel/softirq.c:561
 run_ksoftirqd+0x1c/0x30 kernel/softirq.c:950
 smpboot_thread_fn+0x31c/0x4c0 kernel/smpboot.c:164
 kthread+0x1d1/0x210 kernel/kthread.c:389
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

read to 0xffff88812f452b24 of 4 bytes by task 21332 on cpu 1:
 xa_marked include/linux/xarray.h:424 [inline]
 mapping_tagged include/linux/fs.h:504 [inline]
 filemap_fdatawrite_wbc mm/filemap.c:384 [inline]
 __filemap_fdatawrite_range mm/filemap.c:421 [inline]
 file_write_and_wait_range+0x116/0x2f0 mm/filemap.c:778
 generic_buffers_fsync_noflush+0x46/0x120 fs/buffer.c:600
 ext4_fsync_nojournal fs/ext4/fsync.c:88 [inline]
 ext4_sync_file+0x1ff/0x6c0 fs/ext4/fsync.c:151
 vfs_fsync_range+0x116/0x130 fs/sync.c:187
 generic_write_sync include/linux/fs.h:2904 [inline]
 ext4_buffered_write_iter+0x326/0x370 fs/ext4/file.c:305
 ext4_file_write_iter+0x383/0xf20
 iter_file_splice_write+0x5f1/0x980 fs/splice.c:743
 do_splice_from fs/splice.c:941 [inline]
 direct_splice_actor+0x160/0x2c0 fs/splice.c:1164
 splice_direct_to_actor+0x302/0x670 fs/splice.c:1108
 do_splice_direct_actor fs/splice.c:1207 [inline]
 do_splice_direct+0xd7/0x150 fs/splice.c:1233
 do_sendfile+0x398/0x660 fs/read_write.c:1363
 __do_sys_sendfile64 fs/read_write.c:1424 [inline]
 __se_sys_sendfile64 fs/read_write.c:1410 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1410
 x64_sys_call+0xfbd/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x06000021 -> 0x0a000021

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 21332 Comm: syz.2.7270 Not tainted 6.13.0-rc6-syzkaller-00036-gfbfd64d25c7a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
==================================================================