loop5: detected capacity change from 0 to 512
EXT4-fs: Quota format mount options ignored when QUOTA feature is enabled
EXT4-fs (loop5): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: writeback.
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BUG: KCSAN: data-race in __xa_clear_mark / xas_find_marked

read-write to 0xffff88812e4c6230 of 8 bytes by task 3602 on cpu 1:
 instrument_read_write include/linux/instrumented.h:55 [inline]
 __instrument_read_write_bitop include/asm-generic/bitops/instrumented-non-atomic.h:84 [inline]
 ___test_and_clear_bit include/asm-generic/bitops/instrumented-non-atomic.h:114 [inline]
 node_clear_mark lib/xarray.c:102 [inline]
 xas_clear_mark lib/xarray.c:922 [inline]
 __xa_clear_mark+0xf5/0x1e0 lib/xarray.c:2097
 __folio_end_writeback+0x177/0x470 mm/page-writeback.c:3024
 folio_end_writeback+0x71/0x3d0 mm/filemap.c:1660
 ext4_finish_bio+0x459/0x8c0 fs/ext4/page-io.c:144
 ext4_release_io_end+0x9f/0x1f0 fs/ext4/page-io.c:159
 ext4_end_io_end+0x18d/0x240 fs/ext4/page-io.c:210
 ext4_do_flush_completed_IO fs/ext4/page-io.c:287 [inline]
 ext4_end_io_rsv_work+0x151/0x1e0 fs/ext4/page-io.c:302
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0x4cb/0x9d0 kernel/workqueue.c:3321
 worker_thread+0x582/0x770 kernel/workqueue.c:3402
 kthread+0x489/0x510 kernel/kthread.c:464
 ret_from_fork+0xda/0x150 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read to 0xffff88812e4c6230 of 8 bytes by task 15886 on cpu 0:
 xas_find_chunk include/linux/xarray.h:1752 [inline]
 xas_find_marked+0x218/0x620 lib/xarray.c:1510
 find_get_entry+0x5d/0x380 mm/filemap.c:2038
 filemap_get_folios_tag+0x13b/0x210 mm/filemap.c:2306
 __filemap_fdatawait_range mm/filemap.c:530 [inline]
 file_write_and_wait_range+0x1ea/0x2c0 mm/filemap.c:798
 generic_buffers_fsync_noflush+0x45/0x120 fs/buffer.c:609
 ext4_fsync_nojournal fs/ext4/fsync.c:88 [inline]
 ext4_sync_file+0x1ab/0x690 fs/ext4/fsync.c:147
 vfs_fsync_range+0x10d/0x130 fs/sync.c:187
 generic_write_sync include/linux/fs.h:3031 [inline]
 ext4_buffered_write_iter+0x34f/0x3c0 fs/ext4/file.c:305
 ext4_file_write_iter+0x383/0xf00 fs/ext4/file.c:-1
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x49d/0x8e0 fs/read_write.c:686
 ksys_pwrite64 fs/read_write.c:793 [inline]
 __do_sys_pwrite64 fs/read_write.c:801 [inline]
 __se_sys_pwrite64 fs/read_write.c:798 [inline]
 __x64_sys_pwrite64+0xfd/0x150 fs/read_write.c:798
 x64_sys_call+0xe45/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:19
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00fe000000000000 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 15886 Comm: syz.5.3222 Not tainted 6.16.0-rc6-syzkaller-00037-ge2291551827f #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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