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BUG: KCSAN: data-race in xas_find_marked / xas_set_mark

read-write to 0xffff888106952238 of 8 bytes by task 27198 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_set_bit include/asm-generic/bitops/instrumented-non-atomic.h:99 [inline]
 node_set_mark lib/xarray.c:95 [inline]
 xas_set_mark+0x86/0x140 lib/xarray.c:885
 tag_pages_for_writeback+0xaa/0x2a0 mm/page-writeback.c:2350
 ext4_do_writepages+0x694/0x2100 fs/ext4/inode.c:2615
 ext4_writepages+0x15e/0x2e0 fs/ext4/inode.c:2768
 do_writepages+0x1c2/0x340 mm/page-writeback.c:2553
 filemap_fdatawrite_wbc+0xdb/0xf0 mm/filemap.c:388
 __filemap_fdatawrite_range mm/filemap.c:421 [inline]
 filemap_write_and_wait_range+0xe0/0x210 mm/filemap.c:676
 filemap_write_and_wait include/linux/pagemap.h:64 [inline]
 ext4_bmap+0x14e/0x180 fs/ext4/inode.c:3109
 bmap+0x5a/0x80 fs/inode.c:1790
 ioctl_fibmap fs/ioctl.c:77 [inline]
 file_ioctl fs/ioctl.c:328 [inline]
 do_vfs_ioctl+0x11b5/0x13a0 fs/ioctl.c:850
 __do_sys_ioctl fs/ioctl.c:869 [inline]
 __se_sys_ioctl+0x81/0x140 fs/ioctl.c:857
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

read to 0xffff888106952238 of 8 bytes by task 27197 on cpu 0:
 xas_find_chunk include/linux/xarray.h:1723 [inline]
 xas_find_marked+0x216/0x660 lib/xarray.c:1354
 find_get_entry+0x5d/0x290 mm/filemap.c:1961
 filemap_get_folios_tag+0x9e/0x210 mm/filemap.c:2211
 mpage_prepare_extent_to_map+0x321/0xb70 fs/ext4/inode.c:2392
 ext4_do_writepages+0x6ea/0x2100 fs/ext4/inode.c:2632
 ext4_writepages+0x15e/0x2e0 fs/ext4/inode.c:2768
 do_writepages+0x1c2/0x340 mm/page-writeback.c:2553
 filemap_fdatawrite_wbc+0xdb/0xf0 mm/filemap.c:388
 __filemap_fdatawrite_range mm/filemap.c:421 [inline]
 filemap_write_and_wait_range+0xe0/0x210 mm/filemap.c:676
 ext4_punch_hole+0xc5/0x7e0 fs/ext4/inode.c:3893
 ext4_fallocate+0x209/0x1180 fs/ext4/extents.c:4741
 vfs_fallocate+0x378/0x3e0 fs/open.c:328
 do_vfs_ioctl+0x12e6/0x13a0 fs/ioctl.c:850
 __do_sys_ioctl fs/ioctl.c:869 [inline]
 __se_sys_ioctl+0x81/0x140 fs/ioctl.c:857
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0x0000000000000001 -> 0x0000000000000007

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 27197 Comm: syz-executor.2 Not tainted 6.8.0-rc5-syzkaller-00029-g39133352cbed #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
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