From patchwork Mon Feb 10 13:10:26 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dennis Dalessandro X-Patchwork-Id: 11373225 X-Patchwork-Delegate: jgg@ziepe.ca Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B76DE924 for ; Mon, 10 Feb 2020 13:10:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A267D20708 for ; Mon, 10 Feb 2020 13:10:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729400AbgBJNKn (ORCPT ); Mon, 10 Feb 2020 08:10:43 -0500 Received: from mga07.intel.com ([134.134.136.100]:55385 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729347AbgBJNKb (ORCPT ); Mon, 10 Feb 2020 08:10:31 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga105.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 10 Feb 2020 05:10:30 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,425,1574150400"; d="scan'208";a="431595858" Received: from sedona.ch.intel.com ([10.2.136.157]) by fmsmga005.fm.intel.com with ESMTP; 10 Feb 2020 05:10:29 -0800 Received: from awfm-01.aw.intel.com (awfm-01.aw.intel.com [10.228.212.213]) by sedona.ch.intel.com (8.14.3/8.14.3/Standard MailSET/Hub) with ESMTP id 01ADATnF007521; Mon, 10 Feb 2020 06:10:29 -0700 Received: from awfm-01.aw.intel.com (localhost [127.0.0.1]) by awfm-01.aw.intel.com (8.14.7/8.14.7) with ESMTP id 01ADAQ0Z087642; Mon, 10 Feb 2020 08:10:27 -0500 Subject: [PATCH for-rc 1/3] IB/hfi1: Acquire lock to release TID entries when user file is closed From: Dennis Dalessandro To: jgg@ziepe.ca, dledford@redhat.com Cc: linux-rdma@vger.kernel.org, Mike Marciniszyn , Kaike Wan Date: Mon, 10 Feb 2020 08:10:26 -0500 Message-ID: <20200210131026.87408.86853.stgit@awfm-01.aw.intel.com> In-Reply-To: <20200210130712.87408.34564.stgit@awfm-01.aw.intel.com> References: <20200210130712.87408.34564.stgit@awfm-01.aw.intel.com> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Sender: linux-rdma-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org From: Kaike Wan Each user context is allocated a certain number of RcvArray (TID) entries and these entries are managed through TID groups. These groups are put into one of three lists in each user context: tid_group_list, tid_used_list, and tid_full_list, depending on the number of used TID entries within each group. When TID packets are expected, one or more TID groups will be allocated. After the packets are received, the TID groups will be freed. Since multiple user threads may access the TID groups simultaneously, a mutex exp_mutex is used to synchronize the access. However, when the user file is closed, it tries to release all TID groups without acquiring the mutex first, which risks a race condition with another thread that may be releasing its TID groups, leading to data corruption. This patch addresses the issue by acquiring the mutex first before releasing the TID groups when the file is closed. Fixes: 3abb33ac6521 ("staging/hfi1: Add TID cache receive init and free funcs") Reviewed-by: Mike Marciniszyn Signed-off-by: Kaike Wan Signed-off-by: Dennis Dalessandro --- drivers/infiniband/hw/hfi1/user_exp_rcv.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/infiniband/hw/hfi1/user_exp_rcv.c b/drivers/infiniband/hw/hfi1/user_exp_rcv.c index f05742a..2443423 100644 --- a/drivers/infiniband/hw/hfi1/user_exp_rcv.c +++ b/drivers/infiniband/hw/hfi1/user_exp_rcv.c @@ -142,10 +142,12 @@ void hfi1_user_exp_rcv_free(struct hfi1_filedata *fd) { struct hfi1_ctxtdata *uctxt = fd->uctxt; + mutex_lock(&uctxt->exp_mutex); if (!EXP_TID_SET_EMPTY(uctxt->tid_full_list)) unlock_exp_tids(uctxt, &uctxt->tid_full_list, fd); if (!EXP_TID_SET_EMPTY(uctxt->tid_used_list)) unlock_exp_tids(uctxt, &uctxt->tid_used_list, fd); + mutex_unlock(&uctxt->exp_mutex); kfree(fd->invalid_tids); fd->invalid_tids = NULL;