Commit f6dc5a36 authored by Pavel Begunkov's avatar Pavel Begunkov Committed by Jens Axboe
Browse files

io_uring: fix mixed cqe overflow handling 



I started to see zcrx data corruptions. That turned out to be due
to CQ tail pointing to a stale entry which happened to be from
a zcrx request. I.e. the tail is incremented without the CQE
memory being changed.

The culprit is __io_cqring_overflow_flush() passing "cqe32=true"
to io_get_cqe_overflow() for non-mixed CQE32 setups, which only
expects it to be set for mixed 32B CQEs and not for SETUP_CQE32.

The fix is slightly hacky, long term it's better to unify mixed and
CQE32 handling.

Fixes: e26dca67 ("io_uring: add support for IORING_SETUP_CQE_MIXED")
Signed-off-by: default avatarPavel Begunkov <asml.silence@gmail.com>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent f6041803

io_uring/io_uring.c

+2 −0
Original line number Diff line number Diff line
@@ -634,6 +634,8 @@ static void __io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool dying) 
			is_cqe32 = true;

			cqe_size <<= 1;

		}

		if (ctx->flags & IORING_SETUP_CQE32)

			is_cqe32 = false;



		if (!dying) {

			if (!io_get_cqe_overflow(ctx, &cqe, true, is_cqe32))