RE Jen's proposed patch here https://lore.kernel.org/io-uring/45d7558a-d0c8-4d3f-c63a-33fd2fb073a5@xxxxxxxxx/ and RE what Stefan just mentioned in the "[PATCH 5.11] io_uring: don't take fs for recvmsg/sendmsg" thread a few minutes ago... "Can't we better remove these checks and allow msg_control? For me it's a limitation that I would like to be removed."... which I coincidentally just read when coming on here to advocate the same. I also require this for a few vital performance use cases: 1) GSO (UDP_SEGMENT to sendmsg) 2) GRO (UDP_GRO from recvmsg) GSO and GRO are super important for QUIC servers... essentially bringing a 3-4x performance improvement that brings them in line with TCP efficiency. Would also allow the usage of... 3) MSG_ZEROCOPY (to receive the sock_extended_err from recvmsg) it's only a single digit % performance gain for large sends (but a minor crutch until we get registered buffer sendmsg / recvmsg, which I plan on implementing). So if there's an agreed upon plan on action I can take charge of all the work and get this done ASAP. #Victor
