syzbot

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BUG: KCSAN: data-race in __mark_inode_dirty / __writeback_single_inode

write to 0xffff8881382dbc60 of 8 bytes by task 14036 on cpu 0:
 __writeback_single_inode+0x1f6/0x590 fs/fs-writeback.c:1617
 writeback_sb_inodes+0x69e/0xdd0 fs/fs-writeback.c:1858
 __writeback_inodes_wb+0xb0/0x2a0 fs/fs-writeback.c:1927
 wb_writeback+0x280/0x650 fs/fs-writeback.c:2032
 wb_check_start_all fs/fs-writeback.c:2154 [inline]
 wb_do_writeback+0x418/0x600 fs/fs-writeback.c:2180
 wb_workfn+0x88/0x260 fs/fs-writeback.c:2213
 process_one_work+0x3d3/0x720 kernel/workqueue.c:2289
 worker_thread+0x618/0xa70 kernel/workqueue.c:2436
 kthread+0x1a9/0x1e0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30

read to 0xffff8881382dbc60 of 8 bytes by task 15100 on cpu 1:
 __mark_inode_dirty+0xd5/0x5f0 fs/fs-writeback.c:2392
 mark_inode_dirty include/linux/fs.h:2324 [inline]
 generic_write_end+0x168/0x230 fs/buffer.c:2199
 ext4_da_write_end+0x446/0x510 fs/ext4/inode.c:3068
 generic_perform_write+0x26a/0x3f0 mm/filemap.c:3798
 ext4_buffered_write_iter+0x199/0x280 fs/ext4/file.c:270
 ext4_file_write_iter+0x211/0xdf0
 call_write_iter include/linux/fs.h:2050 [inline]
 new_sync_write fs/read_write.c:504 [inline]
 vfs_write+0x71c/0x890 fs/read_write.c:591
 ksys_write+0xe8/0x1a0 fs/read_write.c:644
 __do_sys_write fs/read_write.c:656 [inline]
 __se_sys_write fs/read_write.c:653 [inline]
 __x64_sys_write+0x3e/0x50 fs/read_write.c:653
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x0000000000020087 -> 0x0000000000020084

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 15100 Comm: syz-executor.1 Not tainted 5.18.0-rc7-syzkaller-00136-g3b5e1590a267-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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