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BUG: KCSAN: data-race in __mark_inode_dirty / writeback_sb_inodes

write to 0xffff888135147ad0 of 8 bytes by task 1141 on cpu 0:
 writeback_sb_inodes+0x3cd/0xd30 fs/fs-writeback.c:1870
 wb_writeback+0x27d/0x6d0 fs/fs-writeback.c:2053
 wb_do_writeback+0x101/0x530 fs/fs-writeback.c:2196
 wb_workfn+0xc8/0x540 fs/fs-writeback.c:2237
 process_one_work+0x402/0x910 kernel/workqueue.c:2297
 worker_thread+0x636/0xae0 kernel/workqueue.c:2444
 kthread+0x262/0x280 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30

read to 0xffff888135147ad0 of 8 bytes by task 3476 on cpu 1:
 __mark_inode_dirty+0xda/0x6a0 fs/fs-writeback.c:2419
 mark_inode_dirty include/linux/fs.h:2452 [inline]
 dquot_alloc_space include/linux/quotaops.h:317 [inline]
 dquot_alloc_block include/linux/quotaops.h:334 [inline]
 ext4_mb_new_blocks+0x119b/0x1fc0 fs/ext4/mballoc.c:5548
 ext4_ext_map_blocks+0x15ed/0x1ff0 fs/ext4/extents.c:4250
 ext4_map_blocks+0x71e/0xf00 fs/ext4/inode.c:637
 ext4_alloc_file_blocks+0x281/0x730 fs/ext4/extents.c:4437
 ext4_fallocate+0x2a7/0x4d0 fs/ext4/extents.c:4718
 vfs_fallocate+0x459/0x6a0 fs/open.c:307
 ksys_fallocate fs/open.c:330 [inline]
 __do_sys_fallocate fs/open.c:338 [inline]
 __se_sys_fallocate fs/open.c:336 [inline]
 __x64_sys_fallocate+0x75/0xc0 fs/open.c:336
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x0000000000020001 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 3476 Comm: syz-executor.2 Not tainted 5.15.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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