==================================================================
BUG: KCSAN: data-race in xas_clear_mark / xas_find_marked

read-write to 0xffff8881067cc6c8 of 8 bytes by task 6047 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+0x90/0x180 lib/xarray.c:915
 __folio_start_writeback+0x2f1/0x430 mm/page-writeback.c:3166
 ext4_bio_write_folio+0x591/0x9d0 fs/ext4/page-io.c:556
 mpage_submit_folio fs/ext4/inode.c:1932 [inline]
 mpage_map_and_submit_buffers fs/ext4/inode.c:2178 [inline]
 mpage_map_and_submit_extent fs/ext4/inode.c:2310 [inline]
 ext4_do_writepages+0x1221/0x2130 fs/ext4/inode.c:2735
 ext4_writepages+0x159/0x2e0 fs/ext4/inode.c:2824
 do_writepages+0x1d8/0x480 mm/page-writeback.c:2708
 filemap_fdatawrite_wbc mm/filemap.c:388 [inline]
 __filemap_fdatawrite_range mm/filemap.c:421 [inline]
 filemap_write_and_wait_range+0x146/0x360 mm/filemap.c:675
 kiocb_write_and_wait+0x73/0x100 mm/filemap.c:2723
 __iomap_dio_rw+0x50c/0x1110 fs/iomap/direct-io.c:626
 iomap_dio_rw+0x40/0x90 fs/iomap/direct-io.c:792
 ext4_dio_read_iter fs/ext4/file.c:94 [inline]
 ext4_file_read_iter+0x214/0x290 fs/ext4/file.c:145
 copy_splice_read+0x3a0/0x5d0 fs/splice.c:365
 do_splice_read fs/splice.c:984 [inline]
 splice_direct_to_actor+0x28b/0x670 fs/splice.c:1089
 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

read to 0xffff8881067cc6c8 of 8 bytes by task 6038 on cpu 0:
 xas_find_chunk include/linux/xarray.h:1733 [inline]
 xas_find_marked+0x216/0x660 lib/xarray.c:1370
 find_get_entry+0x54/0x390 mm/filemap.c:1984
 filemap_get_folios_tag+0x9e/0x210 mm/filemap.c:2251
 mpage_prepare_extent_to_map+0x329/0xb80 fs/ext4/inode.c:2448
 ext4_do_writepages+0x6ea/0x2130 fs/ext4/inode.c:2688
 ext4_writepages+0x159/0x2e0 fs/ext4/inode.c:2824
 do_writepages+0x1d8/0x480 mm/page-writeback.c:2708
 filemap_fdatawrite_wbc mm/filemap.c:388 [inline]
 __filemap_fdatawrite_range mm/filemap.c:421 [inline]
 filemap_write_and_wait_range+0x146/0x360 mm/filemap.c:675
 kiocb_write_and_wait+0x73/0x100 mm/filemap.c:2723
 __iomap_dio_rw+0x50c/0x1110 fs/iomap/direct-io.c:626
 iomap_dio_rw+0x40/0x90 fs/iomap/direct-io.c:792
 ext4_dio_read_iter fs/ext4/file.c:94 [inline]
 ext4_file_read_iter+0x214/0x290 fs/ext4/file.c:145
 copy_splice_read+0x3a0/0x5d0 fs/splice.c:365
 do_splice_read fs/splice.c:984 [inline]
 splice_direct_to_actor+0x28b/0x670 fs/splice.c:1089
 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: 0xfff0000000000000 -> 0xf800000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 6038 Comm: syz.5.770 Not tainted 6.13.0-syzkaller-04858-g21266b8df522 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
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syz.5.770 (6038) used greatest stack depth: 9064 bytes left