From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:40544 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1163763AbeE1KvD (ORCPT ); Mon, 28 May 2018 06:51:03 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Amit Radzi , Michal Kalderon , Ariel Elior , Jason Gunthorpe , Sasha Levin Subject: [PATCH 4.14 220/496] RDMA/qedr: Fix kernel panic when running fio over NFSoRDMA Date: Mon, 28 May 2018 12:00:05 +0200 Message-Id: <20180528100329.187647534@linuxfoundation.org> In-Reply-To: <20180528100319.498712256@linuxfoundation.org> References: <20180528100319.498712256@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: "Kalderon, Michal" [ Upstream commit e3fd112cbf21d049faf64ba1471d72b93c22109a ] Race in qedr_poll_cq, lastest_cqe wasn't protected by lock, leading to a case where two context's accessing poll_cq at the same time lead to one of them having a pointer to an old latest_cqe and reading an invalid cqe element Signed-off-by: Amit Radzi Signed-off-by: Michal Kalderon Signed-off-by: Ariel Elior Signed-off-by: Jason Gunthorpe Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/infiniband/hw/qedr/verbs.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/infiniband/hw/qedr/verbs.c +++ b/drivers/infiniband/hw/qedr/verbs.c @@ -3518,7 +3518,7 @@ int qedr_poll_cq(struct ib_cq *ibcq, int { struct qedr_dev *dev = get_qedr_dev(ibcq->device); struct qedr_cq *cq = get_qedr_cq(ibcq); - union rdma_cqe *cqe = cq->latest_cqe; + union rdma_cqe *cqe; u32 old_cons, new_cons; unsigned long flags; int update = 0; @@ -3535,6 +3535,7 @@ int qedr_poll_cq(struct ib_cq *ibcq, int return qedr_gsi_poll_cq(ibcq, num_entries, wc); spin_lock_irqsave(&cq->cq_lock, flags); + cqe = cq->latest_cqe; old_cons = qed_chain_get_cons_idx_u32(&cq->pbl); while (num_entries && is_valid_cqe(cq, cqe)) { struct qedr_qp *qp;