From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:33716 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730552AbeJBUOH (ORCPT ); Tue, 2 Oct 2018 16:14:07 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Anirudh Venkataramanan , Tony Brelinski , Jeff Kirsher , Sasha Levin Subject: [PATCH 4.18 198/228] ice: Fix bugs in control queue processing Date: Tue, 2 Oct 2018 06:24:55 -0700 Message-Id: <20181002132511.332485495@linuxfoundation.org> In-Reply-To: <20181002132459.032960735@linuxfoundation.org> References: <20181002132459.032960735@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: 4.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Anirudh Venkataramanan [ Upstream commit 3d6b640efcc1b07709b42dd2e9609401c6f88633 ] This patch is a consolidation of multiple bug fixes for control queue processing. 1) In ice_clean_adminq_subtask() remove unnecessary reads/writes to registers. The bits PFINT_FW_CTL, PFINT_MBX_CTL and PFINT_SB_CTL are not set when an interrupt arrives, which means that clearing them again can be omitted. 2) Get an accurate value in "pending" by re-reading the control queue head register from the hardware. 3) Fix a corner case involving lost control queue messages by checking for new control messages (using ice_ctrlq_pending) before exiting the cleanup routine. Signed-off-by: Anirudh Venkataramanan Tested-by: Tony Brelinski Signed-off-by: Jeff Kirsher Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/intel/ice/ice_controlq.c | 5 ++++- drivers/net/ethernet/intel/ice/ice_main.c | 26 ++++++++++++++++++++++---- 2 files changed, 26 insertions(+), 5 deletions(-) --- a/drivers/net/ethernet/intel/ice/ice_controlq.c +++ b/drivers/net/ethernet/intel/ice/ice_controlq.c @@ -1065,8 +1065,11 @@ ice_clean_rq_elem(struct ice_hw *hw, str clean_rq_elem_out: /* Set pending if needed, unlock and return */ - if (pending) + if (pending) { + /* re-read HW head to calculate actual pending messages */ + ntu = (u16)(rd32(hw, cq->rq.head) & cq->rq.head_mask); *pending = (u16)((ntc > ntu ? cq->rq.count : 0) + (ntu - ntc)); + } clean_rq_elem_err: mutex_unlock(&cq->rq_lock); --- a/drivers/net/ethernet/intel/ice/ice_main.c +++ b/drivers/net/ethernet/intel/ice/ice_main.c @@ -917,13 +917,27 @@ static int __ice_clean_ctrlq(struct ice_ } /** + * ice_ctrlq_pending - check if there is a difference between ntc and ntu + * @hw: pointer to hardware info + * @cq: control queue information + * + * returns true if there are pending messages in a queue, false if there aren't + */ +static bool ice_ctrlq_pending(struct ice_hw *hw, struct ice_ctl_q_info *cq) +{ + u16 ntu; + + ntu = (u16)(rd32(hw, cq->rq.head) & cq->rq.head_mask); + return cq->rq.next_to_clean != ntu; +} + +/** * ice_clean_adminq_subtask - clean the AdminQ rings * @pf: board private structure */ static void ice_clean_adminq_subtask(struct ice_pf *pf) { struct ice_hw *hw = &pf->hw; - u32 val; if (!test_bit(__ICE_ADMINQ_EVENT_PENDING, pf->state)) return; @@ -933,9 +947,13 @@ static void ice_clean_adminq_subtask(str clear_bit(__ICE_ADMINQ_EVENT_PENDING, pf->state); - /* re-enable Admin queue interrupt causes */ - val = rd32(hw, PFINT_FW_CTL); - wr32(hw, PFINT_FW_CTL, (val | PFINT_FW_CTL_CAUSE_ENA_M)); + /* There might be a situation where new messages arrive to a control + * queue between processing the last message and clearing the + * EVENT_PENDING bit. So before exiting, check queue head again (using + * ice_ctrlq_pending) and process new messages if any. + */ + if (ice_ctrlq_pending(hw, &hw->adminq)) + __ice_clean_ctrlq(pf, ICE_CTL_Q_ADMIN); ice_flush(hw); }