From patchwork Thu Apr 14 13:13:37 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 561564 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0BC5BC433F5 for ; Thu, 14 Apr 2022 14:04:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241741AbiDNOGy (ORCPT ); Thu, 14 Apr 2022 10:06:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43462 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347587AbiDNN7W (ORCPT ); Thu, 14 Apr 2022 09:59:22 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1600A43497; Thu, 14 Apr 2022 06:50:15 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id B224DB82894; Thu, 14 Apr 2022 13:50:13 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id EF0D9C385A9; Thu, 14 Apr 2022 13:50:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1649944212; bh=w17I2GFNMzwU5tGUrCqoLz9FROTmjllgoGdb7huj748=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=G5HMh3wlnOgE0n1mb7HXuMJvYYfz1kMy3m4mciXHSY1Qotgqnkt0Vm/sdkKu1kG25 R4AONZRHQ4QwhfzBeWyKwr/t1fw58QCQQPKff5MmpLH3vMilo2VH0Ba5FsbTYnIr1z DBMQim/lDtr5lLte3qyRavYyeLC8E9qvPWVRLQIE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Niels Dossche , Dennis Dalessandro , Jason Gunthorpe , Sasha Levin Subject: [PATCH 5.4 432/475] IB/rdmavt: add lock to call to rvt_error_qp to prevent a race condition Date: Thu, 14 Apr 2022 15:13:37 +0200 Message-Id: <20220414110907.153690997@linuxfoundation.org> X-Mailer: git-send-email 2.35.2 In-Reply-To: <20220414110855.141582785@linuxfoundation.org> References: <20220414110855.141582785@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Niels Dossche [ Upstream commit 4d809f69695d4e7d1378b3a072fa9aef23123018 ] The documentation of the function rvt_error_qp says both r_lock and s_lock need to be held when calling that function. It also asserts using lockdep that both of those locks are held. However, the commit I referenced in Fixes accidentally makes the call to rvt_error_qp in rvt_ruc_loopback no longer covered by r_lock. This results in the lockdep assertion failing and also possibly in a race condition. Fixes: d757c60eca9b ("IB/rdmavt: Fix concurrency panics in QP post_send and modify to error") Link: https://lore.kernel.org/r/20220228165330.41546-1-dossche.niels@gmail.com Signed-off-by: Niels Dossche Acked-by: Dennis Dalessandro Signed-off-by: Jason Gunthorpe Signed-off-by: Sasha Levin --- drivers/infiniband/sw/rdmavt/qp.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/infiniband/sw/rdmavt/qp.c b/drivers/infiniband/sw/rdmavt/qp.c index a5152f097cb7..48e8612c1bc8 100644 --- a/drivers/infiniband/sw/rdmavt/qp.c +++ b/drivers/infiniband/sw/rdmavt/qp.c @@ -3227,7 +3227,11 @@ void rvt_ruc_loopback(struct rvt_qp *sqp) spin_lock_irqsave(&sqp->s_lock, flags); rvt_send_complete(sqp, wqe, send_status); if (sqp->ibqp.qp_type == IB_QPT_RC) { - int lastwqe = rvt_error_qp(sqp, IB_WC_WR_FLUSH_ERR); + int lastwqe; + + spin_lock(&sqp->r_lock); + lastwqe = rvt_error_qp(sqp, IB_WC_WR_FLUSH_ERR); + spin_unlock(&sqp->r_lock); sqp->s_flags &= ~RVT_S_BUSY; spin_unlock_irqrestore(&sqp->s_lock, flags);