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BUG: KCSAN: data-race in __mark_inode_dirty / writeback_single_inode

write to 0xffff888109c52640 of 8 bytes by task 9319 on cpu 0:
 writeback_single_inode+0x10e/0x4a0 fs/fs-writeback.c:1721
 sync_inode_metadata+0x56/0x80 fs/fs-writeback.c:2786
 generic_buffers_fsync_noflush+0xe4/0x120 fs/buffer.c:624
 ext4_fsync_nojournal fs/ext4/fsync.c:88 [inline]
 ext4_sync_file+0x1f2/0x6c0 fs/ext4/fsync.c:152
 vfs_fsync_range+0x111/0x120 fs/sync.c:188
 generic_write_sync include/linux/fs.h:2493 [inline]
 ext4_buffered_write_iter+0x334/0x370 fs/ext4/file.c:305
 ext4_file_write_iter+0x283/0x1230
 do_iter_write+0x4b4/0x7b0 fs/read_write.c:860
 vfs_iter_write+0x56/0x70 fs/read_write.c:901
 iter_file_splice_write+0x462/0x7e0 fs/splice.c:739
 do_splice_from fs/splice.c:934 [inline]
 direct_splice_actor+0x8a/0xb0 fs/splice.c:1143
 splice_direct_to_actor+0x31d/0x690 fs/splice.c:1089
 do_splice_direct+0x10d/0x190 fs/splice.c:1195
 do_sendfile+0x3b6/0x9a0 fs/read_write.c:1254
 __do_sys_sendfile64 fs/read_write.c:1322 [inline]
 __se_sys_sendfile64 fs/read_write.c:1308 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1308
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff888109c52640 of 8 bytes by task 9308 on cpu 1:
 __mark_inode_dirty+0x199/0x7d0 fs/fs-writeback.c:2452
 mark_buffer_dirty+0x165/0x240 fs/buffer.c:1221
 __block_commit_write fs/buffer.c:2202 [inline]
 block_write_end+0x158/0x2e0 fs/buffer.c:2280
 ext4_write_end+0x176/0x820 fs/ext4/inode.c:1277
 ext4_da_write_end+0xac/0x700 fs/ext4/inode.c:2952
 generic_perform_write+0x26d/0x410 mm/filemap.c:3934
 ext4_buffered_write_iter+0x1f6/0x370 fs/ext4/file.c:299
 ext4_file_write_iter+0x283/0x1230
 do_iter_write+0x4b4/0x7b0 fs/read_write.c:860
 vfs_iter_write+0x56/0x70 fs/read_write.c:901
 iter_file_splice_write+0x462/0x7e0 fs/splice.c:739
 do_splice_from fs/splice.c:934 [inline]
 direct_splice_actor+0x8a/0xb0 fs/splice.c:1143
 splice_direct_to_actor+0x31d/0x690 fs/splice.c:1089
 do_splice_direct+0x10d/0x190 fs/splice.c:1195
 do_sendfile+0x3b6/0x9a0 fs/read_write.c:1254
 __do_sys_sendfile64 fs/read_write.c:1322 [inline]
 __se_sys_sendfile64 fs/read_write.c:1308 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1308
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x0000000000000005 -> 0x0000000000000084

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 9308 Comm: syz-executor.3 Not tainted 6.5.0-rc1-syzkaller-00276-g20edcec23f92 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/03/2023
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