From patchwork Fri May 24 15:44:38 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dennis Dalessandro X-Patchwork-Id: 10960051 X-Patchwork-Delegate: jgg@ziepe.ca Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B022376 for ; Fri, 24 May 2019 15:44:43 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9E39E28801 for ; Fri, 24 May 2019 15:44:43 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 9A02C28957; Fri, 24 May 2019 15:44:43 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3A13928801 for ; Fri, 24 May 2019 15:44:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390114AbfEXPom (ORCPT ); Fri, 24 May 2019 11:44:42 -0400 Received: from mga18.intel.com ([134.134.136.126]:46396 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389950AbfEXPom (ORCPT ); Fri, 24 May 2019 11:44:42 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by orsmga106.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 24 May 2019 08:44:41 -0700 X-ExtLoop1: 1 Received: from sedona.ch.intel.com ([10.2.136.157]) by fmsmga007.fm.intel.com with ESMTP; 24 May 2019 08:44:41 -0700 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 x4OFievj006134; Fri, 24 May 2019 08:44:40 -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 x4OFicuE010669; Fri, 24 May 2019 11:44:39 -0400 Subject: [PATCH for-rc 1/5] IB/rdmavt: Fix alloc_qpn() WARN_ON() From: Dennis Dalessandro To: jgg@ziepe.ca, dledford@redhat.com Cc: linux-rdma@vger.kernel.org, Mike Marciniszyn , Kaike Wan Date: Fri, 24 May 2019 11:44:38 -0400 Message-ID: <20190524154438.10588.41702.stgit@awfm-01.aw.intel.com> In-Reply-To: <20190524154320.10588.44693.stgit@awfm-01.aw.intel.com> References: <20190524154320.10588.44693.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 X-Virus-Scanned: ClamAV using ClamSMTP From: Mike Marciniszyn The qpn allocation logic has a WARN_ON() that intends to detect the use of an index that will introduce bits in the lower order bits of the QOS bits in the QPN. Unfortunately, it has the following bugs: - it misfires when wrapping QPN allocation for non-QOS - it doesn't correctly detect low order QOS bits (despite the comment) The WARN_ON() should not be applied to non-QOS (qos_shift == 1). Additionally, it SHOULD test the qpn bits per the table below: 2 data VLs: [qp7, qp6, qp5, qp4, qp3, qp2, qp1] ^ [ 0, 0, 0, 0, 0, 0, sc0], qp bit 1 always 0* 3-4 data VLs: [qp7, qp6, qp5, qp4, qp3, qp2, qp1] ^ [ 0, 0, 0, 0, 0, sc1, sc0], qp bits [21] always 0 5-8 data VLs: [qp7, qp6, qp5, qp4, qp3, qp2, qp1] ^ [ 0, 0, 0, 0, sc2, sc1, sc0] qp bits [321] always 0 Fix by qualifying the warning for qos_shift > 1 and producing the correct mask to insure the above bits are zero without generating a superfluous warning. Fixes: 501edc42446e ("IB/rdmavt: Correct warning during QPN allocation") Reviewed-by: Kaike Wan Signed-off-by: Mike Marciniszyn Signed-off-by: Dennis Dalessandro --- drivers/infiniband/sw/rdmavt/qp.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/infiniband/sw/rdmavt/qp.c b/drivers/infiniband/sw/rdmavt/qp.c index 31a2e65..c5a5061 100644 --- a/drivers/infiniband/sw/rdmavt/qp.c +++ b/drivers/infiniband/sw/rdmavt/qp.c @@ -594,7 +594,8 @@ static int alloc_qpn(struct rvt_dev_info *rdi, struct rvt_qpn_table *qpt, offset = qpt->incr | ((offset & 1) ^ 1); } /* there can be no set bits in low-order QoS bits */ - WARN_ON(offset & (BIT(rdi->dparms.qos_shift) - 1)); + WARN_ON(rdi->dparms.qos_shift > 1 && + offset & ((BIT(rdi->dparms.qos_shift - 1) - 1) << 1)); qpn = mk_qpn(qpt, map, offset); }