Right. I think being able to restore the crtime (as root) makes sense, I don't think restoring i_generation and i_version make sense however, given that we can't preserve the inode number. The filesystem can silently ignore them when they are written as xattrs (returning an error gives "tar" and "cp" heartburn, we've found).
"trusted." is only writeable by root and the kernel. "user." is writeable by regular users.
Cheers, Andreas
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