Use Extra 64 bits in extended cqe

[JkshirsagarMaxlinear]

Hello @axboe ,
I am enabling extended cqe by setting the flag 'IORING_SETUP_CQE32'. While I am able to use the extra1 (64 bits) from 'struct io_kiocb' and read the data in userspace with __u64 big_cqe[0], I see in kernel driver that the 'io_req_set_cqe32_extra' function only takes an input for extra1 and forces extra2 to be 0.
It restricts me from using an additional 64 bits available for cqe. Can you please let me know if there is any better way to access that available extra memory?
I am using Liburing version 2.5 and Linux kernel version as 6.1.132.

[axboe]

There are no in-kernel users of using the latter half of the bigger CQE, which is why it's just cleared to 0. If you have kernel code using it, then yes you'd want to patch that part first. That obviously need to happen on current development kernel, not in an old stable kernel.

[JkshirsagarMaxlinear]

Thank you very much @axboe for the clarification.