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BUG: KCSAN: data-race in __mark_inode_dirty / writeback_single_inode

write to 0xffff88813b6023c0 of 8 bytes by task 23443 on cpu 0:
 writeback_single_inode+0x10e/0x4a0 fs/fs-writeback.c:1721
 sync_inode_metadata+0x56/0x80 fs/fs-writeback.c:2780
 ext4_fsync_nojournal fs/ext4/fsync.c:92 [inline]
 ext4_sync_file+0x36a/0x730 fs/ext4/fsync.c:168
 vfs_fsync_range+0x111/0x120 fs/sync.c:188
 generic_write_sync include/linux/fs.h:2494 [inline]
 ext4_buffered_write_iter+0x3a3/0x3e0 fs/ext4/file.c:307
 ext4_file_write_iter+0xdd/0x10f0
 do_iter_write+0x4b4/0x7b0 fs/read_write.c:860
 vfs_iter_write+0x56/0x70 fs/read_write.c:901
 iter_file_splice_write+0x456/0x7d0 fs/splice.c:762
 do_splice_from fs/splice.c:840 [inline]
 direct_splice_actor+0x8a/0xb0 fs/splice.c:1027
 splice_direct_to_actor+0x349/0x660 fs/splice.c:982
 do_splice_direct+0x104/0x180 fs/splice.c:1070
 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 0xffff88813b6023c0 of 8 bytes by task 23432 on cpu 1:
 __mark_inode_dirty+0x199/0x7d0 fs/fs-writeback.c:2446
 mark_buffer_dirty+0x165/0x240 fs/buffer.c:1157
 __block_commit_write+0x10a/0x1a0 fs/buffer.c:2137
 block_write_end+0x44/0x90 fs/buffer.c:2216
 ext4_write_end+0x174/0x840 fs/ext4/inode.c:1292
 ext4_da_write_end+0x73/0x690 fs/ext4/inode.c:2977
 generic_perform_write+0x253/0x3d0 mm/filemap.c:3957
 ext4_buffered_write_iter+0x240/0x3e0 fs/ext4/file.c:300
 ext4_file_write_iter+0xdd/0x10f0
 do_iter_write+0x4b4/0x7b0 fs/read_write.c:860
 vfs_iter_write+0x56/0x70 fs/read_write.c:901
 iter_file_splice_write+0x456/0x7d0 fs/splice.c:762
 do_splice_from fs/splice.c:840 [inline]
 direct_splice_actor+0x8a/0xb0 fs/splice.c:1027
 splice_direct_to_actor+0x349/0x660 fs/splice.c:982
 do_splice_direct+0x104/0x180 fs/splice.c:1070
 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: 0x0000000000000007 -> 0x0000000000000084

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 23432 Comm: syz-executor.5 Not tainted 6.4.0-syzkaller-01761-g6aeadf7896bf #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
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