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BUG: KCSAN: data-race in find_get_pages_range_tag / xas_init_marks

write to 0xffff888027829478 of 8 bytes by task 25710 on cpu 1:
 instrument_write include/linux/instrumented.h:42 [inline]
 __instrument_read_write_bitop include/asm-generic/bitops/instrumented-non-atomic.h:79 [inline]
 __test_and_clear_bit include/asm-generic/bitops/instrumented-non-atomic.h:109 [inline]
 node_clear_mark lib/xarray.c:100 [inline]
 xas_clear_mark lib/xarray.c:911 [inline]
 xas_init_marks+0x1b0/0x340 lib/xarray.c:944
 xas_store+0x201/0xcf0 lib/xarray.c:806
 page_cache_delete_batch mm/filemap.c:337 [inline]
 delete_from_page_cache_batch+0x3f4/0x820 mm/filemap.c:358
 truncate_inode_pages_range+0x482/0x10e0 mm/truncate.c:366
 truncate_inode_pages mm/truncate.c:476 [inline]
 truncate_pagecache+0x4f/0x70 mm/truncate.c:845
 ext4_setattr+0xae3/0xf60 fs/ext4/inode.c:5500
 notify_change+0x86d/0xa60 fs/attr.c:336
 do_truncate+0xe0/0x120 fs/open.c:64
 handle_truncate fs/namei.c:2912 [inline]
 do_open fs/namei.c:3258 [inline]
 path_openat+0x1a30/0x20a0 fs/namei.c:3371
 do_filp_open+0xbd/0x1d0 fs/namei.c:3398
 do_sys_openat2+0xa3/0x250 fs/open.c:1172
 do_sys_open fs/open.c:1188 [inline]
 __do_sys_creat fs/open.c:1262 [inline]
 __se_sys_creat fs/open.c:1256 [inline]
 __x64_sys_creat+0x62/0x80 fs/open.c:1256
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888027829478 of 8 bytes by task 25689 on cpu 0:
 xas_find_chunk include/linux/xarray.h:1660 [inline]
 xas_next_marked include/linux/xarray.h:1691 [inline]
 find_get_pages_range_tag+0x35c/0x600 mm/filemap.c:2107
 pagevec_lookup_range_tag+0x37/0x50 mm/swap.c:1122
 mpage_prepare_extent_to_map+0x195/0x640 fs/ext4/inode.c:2578
 ext4_writepages+0x674/0x1e70 fs/ext4/inode.c:2755
 do_writepages+0x7b/0x150 mm/page-writeback.c:2352
 __filemap_fdatawrite_range+0x19d/0x1d0 mm/filemap.c:422
 file_write_and_wait_range+0x9f/0x120 mm/filemap.c:761
 ext4_sync_file+0x105/0x6e0 fs/ext4/fsync.c:151
 vfs_fsync_range+0x107/0x120 fs/sync.c:200
 generic_write_sync include/linux/fs.h:2737 [inline]
 ext4_buffered_write_iter+0x38f/0x3e0 fs/ext4/file.c:278
 ext4_file_write_iter+0x47a/0x1060 fs/ext4/file.c:503
 call_write_iter include/linux/fs.h:1901 [inline]
 new_sync_write fs/read_write.c:518 [inline]
 vfs_write+0x6f0/0x7e0 fs/read_write.c:605
 ksys_write+0xce/0x180 fs/read_write.c:658
 __do_sys_write fs/read_write.c:670 [inline]
 __se_sys_write fs/read_write.c:667 [inline]
 __x64_sys_write+0x3e/0x50 fs/read_write.c:667
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 25689 Comm: syz-executor.2 Not tainted 5.11.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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