From df6d3422d3eed27afa23df092b3ce147c558d1a8 Mon Sep 17 00:00:00 2001 From: Pavel Begunkov Date: Tue, 6 Sep 2022 17:11:16 +0100 Subject: [PATCH] io_uring/kbuf: fix not advancing READV kbuf ring When we don't recycle a selected ring buffer we should advance the head of the ring, so don't just skip io_kbuf_recycle() for IORING_OP_READV but adjust the ring. Fixes: 934447a603b22 ("io_uring: do not recycle buffer in READV") Signed-off-by: Pavel Begunkov Reviewed-by: Dylan Yudaken Link: https://lore.kernel.org/r/a6d85e2611471bcb5d5dcd63a8342077ddc2d73d.1662480490.git.asml.silence@gmail.com Signed-off-by: Jens Axboe --- io_uring/kbuf.h | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/io_uring/kbuf.h b/io_uring/kbuf.h index d6af208d109f..746fbf31a703 100644 --- a/io_uring/kbuf.h +++ b/io_uring/kbuf.h @@ -91,9 +91,13 @@ static inline void io_kbuf_recycle(struct io_kiocb *req, unsigned issue_flags) * buffer data. However if that buffer is recycled the original request * data stored in addr is lost. Therefore forbid recycling for now. */ - if (req->opcode == IORING_OP_READV) + if (req->opcode == IORING_OP_READV) { + if ((req->flags & REQ_F_BUFFER_RING) && req->buf_list) { + req->buf_list->head++; + req->buf_list = NULL; + } return; - + } if (req->flags & REQ_F_BUFFER_SELECTED) io_kbuf_recycle_legacy(req, issue_flags); if (req->flags & REQ_F_BUFFER_RING) -- 2.25.1