EXT4-fs (loop0): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none.
ext4 filesystem being mounted at /171/file0 supports timestamps until 2038-01-19 (0x7fffffff)
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BUG: KCSAN: data-race in xas_find_marked / xas_init_marks

read-write to 0xffff888107354fe0 of 8 bytes by task 11876 on cpu 0:
 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]
 xas_init_marks+0x18a/0x320 lib/xarray.c:955
 xas_store+0x3cf/0xce0 lib/xarray.c:817
 page_cache_delete mm/filemap.c:141 [inline]
 __filemap_remove_folio+0x195/0x2a0 mm/filemap.c:227
 folio_unmap_invalidate+0x1dd/0x360 mm/truncate.c:622
 filemap_end_dropbehind mm/filemap.c:1616 [inline]
 folio_end_dropbehind+0x127/0x240 mm/filemap.c:1637
 folio_end_writeback+0x24/0x70 mm/filemap.c:1695
 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:290 [inline]
 ext4_end_io_rsv_work+0x151/0x1e0 fs/ext4/page-io.c:305
 process_one_work kernel/workqueue.c:3263 [inline]
 process_scheduled_works+0x4ce/0x9d0 kernel/workqueue.c:3346
 worker_thread+0x582/0x770 kernel/workqueue.c:3427
 kthread+0x489/0x510 kernel/kthread.c:463
 ret_from_fork+0x122/0x1b0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read to 0xffff888107354fe0 of 8 bytes by task 15483 on cpu 1:
 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:2070
 filemap_get_folios_tag+0x13b/0x210 mm/filemap.c:2338
 __filemap_fdatawait_range mm/filemap.c:533 [inline]
 file_write_and_wait_range+0x1ea/0x2c0 mm/filemap.c:801
 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:3045 [inline]
 ext4_buffered_write_iter+0x34f/0x3c0 fs/ext4/file.c:305
 ext4_file_write_iter+0x387/0xf60 fs/ext4/file.c:-1
 aio_write+0x2e5/0x410 fs/aio.c:1634
 __io_submit_one fs/aio.c:-1 [inline]
 io_submit_one+0xacd/0x11d0 fs/aio.c:2053
 __do_sys_io_submit fs/aio.c:2112 [inline]
 __se_sys_io_submit+0xfb/0x280 fs/aio.c:2082
 __x64_sys_io_submit+0x43/0x50 fs/aio.c:2082
 x64_sys_call+0x2d6c/0x3000 arch/x86/include/generated/asm/syscalls_64.h:210
 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: 0xffffffffffc00000 -> 0xfffffffff8000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 15483 Comm: syz.0.4065 Tainted: G        W           syzkaller #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
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