On 1/22/21 9:07 PM, Jakub Kicinski wrote:
> On Wed, 20 Jan 2021 16:41:48 -0800 Arjun Roy wrote:
>> diff --git a/include/uapi/linux/tcp.h b/include/uapi/linux/tcp.h
>> index 768e93bd5b51..b216270105af 100644
>> --- a/include/uapi/linux/tcp.h
>> +++ b/include/uapi/linux/tcp.h
>> @@ -353,5 +353,9 @@ struct tcp_zerocopy_receive {
>> __u64 copybuf_address; /* in: copybuf address (small reads) */
>> __s32 copybuf_len; /* in/out: copybuf bytes avail/used or error */
>> __u32 flags; /* in: flags */
>> + __u64 msg_control; /* ancillary data */
>> + __u64 msg_controllen;
>> + __u32 msg_flags;
>> + /* __u32 hole; Next we must add >1 u32 otherwise length checks fail. */
>
> Well, let's hope nobody steps on this landmine.. :)
>
Past suggestions were made to use anonymous declarations - e.g., __u32
:32; - as a way of reserving the space for future use. That or declare
'__u32 resvd', check that it must be 0 and makes it available for later
(either directly or with a union).
