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BUG: KCSAN: data-race in fuse_set_nowrite / fuse_writepage_end

write to 0xffff88800b7659b8 of 4 bytes by task 20770 on cpu 1:
 fuse_writepage_end+0x458/0x750 fs/fuse/file.c:1801
 fuse_request_end+0x78b/0x7c0 fs/fuse/dev.c:332
 end_requests fs/fuse/dev.c:2067 [inline]
 fuse_abort_conn+0xab5/0xb10 fs/fuse/dev.c:2162
 fuse_dev_release+0x2b6/0x300 fs/fuse/dev.c:2197
 __fput+0x24e/0x4e0 fs/file_table.c:280
 ____fput+0x11/0x20 fs/file_table.c:313
 task_work_run+0x8e/0x110 kernel/task_work.c:140
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:174 [inline]
 exit_to_user_mode_prepare+0x17c/0x1b0 kernel/entry/common.c:201
 __syscall_exit_to_user_mode_work kernel/entry/common.c:283 [inline]
 syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:294
 do_syscall_64+0x45/0x80 arch/x86/entry/common.c:56
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88800b7659b8 of 4 bytes by task 20773 on cpu 0:
 fuse_set_nowrite+0x12d/0x180 fs/fuse/dir.c:1513
 fuse_sync_writes fs/fuse/file.c:462 [inline]
 fuse_fsync+0xfc/0x2b0 fs/fuse/file.c:561
 vfs_fsync_range+0x107/0x120 fs/sync.c:200
 generic_write_sync include/linux/fs.h:2737 [inline]
 generic_file_write_iter+0x103/0x130 mm/filemap.c:3577
 fuse_cache_write_iter fs/fuse/file.c:1288 [inline]
 fuse_file_write_iter+0x617/0x850 fs/fuse/file.c:1601
 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+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 20773 Comm: syz-executor.4 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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