From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 61764C31E5D for ; Mon, 17 Jun 2019 21:32:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2AEB920657 for ; Mon, 17 Jun 2019 21:32:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1560807153; bh=FSFXtZJkL9X7zdl8EW5+2gIrlqAmjxup/ATjnuMEnyo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=kCgkzbCfCPXP02rKmbNBWFFZj7c8aTGO1kI87itS/7f+rHJv97Hc0HYqx0YrmMhtC gQiVQRZNVblGZPOHs0Kup+fDaIchmAEY5+UcPhqDbYIGy//ukSf7QIr6E7pWeCNi/k QRbFPZEMW+YpbggiV0Sb1dRANMmsFF0AncZgK5YI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729916AbfFQV1c (ORCPT ); Mon, 17 Jun 2019 17:27:32 -0400 Received: from mail.kernel.org ([198.145.29.99]:54562 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728967AbfFQV1c (ORCPT ); Mon, 17 Jun 2019 17:27:32 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 955E2208E4; Mon, 17 Jun 2019 21:27:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1560806851; bh=FSFXtZJkL9X7zdl8EW5+2gIrlqAmjxup/ATjnuMEnyo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tEjzN2LrCXkfVCHwyTgniEHXoKU+d4nQHH8Nnjzlo/FyhP0RrRxApEfVCVUXin6NL pGNFrp+waxchbl2ezaGCYVW9h5gDvD0C/KCq6nitKGaT9JJ+sAMVx41tgHuBpe/KTv d1vy6kn7ll2EskRcUEMReDdQXIDDEhNjqHX/OnNA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Prarit Bhargava , Thomas Gleixner , Fenghua Yu , Reinette Chatre , Borislav Petkov , "H. Peter Anvin" Subject: [PATCH 4.19 72/75] x86/resctrl: Prevent NULL pointer dereference when local MBM is disabled Date: Mon, 17 Jun 2019 23:10:23 +0200 Message-Id: <20190617210756.057833262@linuxfoundation.org> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190617210752.799453599@linuxfoundation.org> References: <20190617210752.799453599@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Prarit Bhargava commit c7563e62a6d720aa3b068e26ddffab5f0df29263 upstream. Booting with kernel parameter "rdt=cmt,mbmtotal,memlocal,l3cat,mba" and executing "mount -t resctrl resctrl -o mba_MBps /sys/fs/resctrl" results in a NULL pointer dereference on systems which do not have local MBM support enabled.. BUG: kernel NULL pointer dereference, address: 0000000000000020 PGD 0 P4D 0 Oops: 0000 [#1] SMP PTI CPU: 0 PID: 722 Comm: kworker/0:3 Not tainted 5.2.0-0.rc3.git0.1.el7_UNSUPPORTED.x86_64 #2 Workqueue: events mbm_handle_overflow RIP: 0010:mbm_handle_overflow+0x150/0x2b0 Only enter the bandwith update loop if the system has local MBM enabled. Fixes: de73f38f7680 ("x86/intel_rdt/mba_sc: Feedback loop to dynamically update mem bandwidth") Signed-off-by: Prarit Bhargava Signed-off-by: Thomas Gleixner Cc: Fenghua Yu Cc: Reinette Chatre Cc: Borislav Petkov Cc: "H. Peter Anvin" Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20190610171544.13474-1-prarit@redhat.com Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/cpu/intel_rdt_monitor.c | 3 +++ 1 file changed, 3 insertions(+) --- a/arch/x86/kernel/cpu/intel_rdt_monitor.c +++ b/arch/x86/kernel/cpu/intel_rdt_monitor.c @@ -371,6 +371,9 @@ static void update_mba_bw(struct rdtgrou struct list_head *head; struct rdtgroup *entry; + if (!is_mbm_local_enabled()) + return; + r_mba = &rdt_resources_all[RDT_RESOURCE_MBA]; closid = rgrp->closid; rmid = rgrp->mon.rmid;