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BUG: KCSAN: data-race in ext4_es_is_delayed / ext4_es_lookup_extent

write to 0xffff8880ba599598 of 8 bytes by task 29 on cpu 0:
 ext4_es_set_referenced fs/ext4/extents_status.h:194 [inline]
 ext4_es_lookup_extent+0x296/0x4f0 fs/ext4/extents_status.c:950
 ext4_map_blocks+0xad/0xf40 fs/ext4/inode.c:517
 mpage_map_one_extent+0x10d/0x3c0 fs/ext4/inode.c:2376
 mpage_map_and_submit_extent fs/ext4/inode.c:2429 [inline]
 ext4_writepages+0xa4c/0x1ef0 fs/ext4/inode.c:2781
 do_writepages+0x7b/0x150 mm/page-writeback.c:2352
 __writeback_single_inode+0x84/0x600 fs/fs-writeback.c:1461
 writeback_sb_inodes+0x6c0/0xff0 fs/fs-writeback.c:1721
 wb_writeback+0x28d/0x6f0 fs/fs-writeback.c:1894
 wb_do_writeback+0x101/0x5f0 fs/fs-writeback.c:2039
 wb_workfn+0xc8/0x470 fs/fs-writeback.c:2080
 process_one_work+0x3e1/0x9a0 kernel/workqueue.c:2269
 worker_thread+0x665/0xbe0 kernel/workqueue.c:2415
 kthread+0x20d/0x230 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

read to 0xffff8880ba599598 of 8 bytes by task 19345 on cpu 1:
 ext4_es_type fs/ext4/extents_status.h:159 [inline]
 ext4_es_is_delayed+0x12/0x20 fs/ext4/extents_status.h:174
 __es_find_extent_range+0x1d5/0x330 fs/ext4/extents_status.c:285
 ext4_es_find_extent_range+0x47/0x210 fs/ext4/extents_status.c:317
 ext4_ext_put_gap_in_cache fs/ext4/extents.c:2236 [inline]
 ext4_ext_map_blocks+0xca7/0x20c0 fs/ext4/extents.c:4142
 ext4_da_map_blocks fs/ext4/inode.c:1741 [inline]
 ext4_da_get_block_prep+0x3f1/0x990 fs/ext4/inode.c:1818
 ext4_block_write_begin+0x433/0xb60 fs/ext4/inode.c:1060
 ext4_da_write_begin+0x507/0xad0 fs/ext4/inode.c:2996
 generic_perform_write+0x196/0x390 mm/filemap.c:3403
 ext4_buffered_write_iter+0x2cc/0x3b0 fs/ext4/file.c:269
 ext4_file_write_iter+0x768/0x1060 include/linux/fs.h:784
 call_write_iter include/linux/fs.h:1882 [inline]
 do_iter_readv_writev+0x32e/0x3d0 fs/read_write.c:713
 do_iter_write+0x112/0x4b0 fs/read_write.c:1018
 vfs_iter_write+0x4c/0x70 fs/read_write.c:1059
 iter_file_splice_write+0x41a/0x770 fs/splice.c:750
 do_splice_from fs/splice.c:846 [inline]
 direct_splice_actor+0x95/0x160 fs/splice.c:1016
 splice_direct_to_actor+0x365/0x660 fs/splice.c:971
 do_splice_direct+0xf2/0x170 fs/splice.c:1059
 do_sendfile+0x56a/0xba0 fs/read_write.c:1540
 __do_sys_sendfile64 fs/read_write.c:1601 [inline]
 __se_sys_sendfile64 fs/read_write.c:1587 [inline]
 __x64_sys_sendfile64+0xf2/0x130 fs/read_write.c:1587
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 19345 Comm: syz-executor.0 Not tainted 5.9.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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