From patchwork Thu Mar 18 10:13:22 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jan Beulich X-Patchwork-Id: 12147821 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=-17.2 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=ham 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 942EBC433E0 for ; Thu, 18 Mar 2021 10:13:44 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 4EE8464E21 for ; Thu, 18 Mar 2021 10:13:44 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4EE8464E21 Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from list by lists.xenproject.org with outflank-mailman.98871.187819 (Exim 4.92) (envelope-from ) id 1lMpef-0007Mz-9o; Thu, 18 Mar 2021 10:13:25 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 98871.187819; Thu, 18 Mar 2021 10:13:25 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lMpef-0007Ms-6b; Thu, 18 Mar 2021 10:13:25 +0000 Received: by outflank-mailman (input) for mailman id 98871; Thu, 18 Mar 2021 10:13:24 +0000 Received: from all-amaz-eas1.inumbo.com ([34.197.232.57] helo=us1-amaz-eas2.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lMpee-0007Mm-6W for xen-devel@lists.xenproject.org; Thu, 18 Mar 2021 10:13:24 +0000 Received: from mx2.suse.de (unknown [195.135.220.15]) by us1-amaz-eas2.inumbo.com (Halon) with ESMTPS id 442177c9-9ab5-4fee-8f59-82895bfbff01; Thu, 18 Mar 2021 10:13:23 +0000 (UTC) Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id B1ABFAC1E; Thu, 18 Mar 2021 10:13:22 +0000 (UTC) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 442177c9-9ab5-4fee-8f59-82895bfbff01 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1616062402; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Y1982WR6j3cpgGsFbVcaDaicMn2WceMWsDl7cYZX9Vg=; b=lFyVfQDVjWzAMl2oA21/i6bVwBTG2NkB0Ir071fgQUFk7xuVaNo6YWTMpzmSUTxn75dWFz NVfq/T6tgSTXsnH0sfXJis3oN6Byhs4bBnvi1bkf909pavpl4m7t5+wW8VvApdjIr0ZkGh UqsCwVlrqcL6xPC/pH+lBbFqA7mjM90= Subject: [PATCH 1/4][4.15?] VT-d: correct off-by-1 in number-of-IOMMUs check From: Jan Beulich To: "xen-devel@lists.xenproject.org" Cc: Kevin Tian , Ian Jackson References: Message-ID: <68084b4f-bcd2-59dd-bea7-781b8aa75ef7@suse.com> Date: Thu, 18 Mar 2021 11:13:22 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.8.1 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US Otherwise, if we really run on a system with this many IOMMUs, entering/leaving S3 would overrun iommu_state[]. Signed-off-by: Jan Beulich --- There are more anomalies here, but since we were asked to not make any cosmetic changes for patches to have a chance to go into 4.15, I've put off correcting even the most obvious things (scope of MAX_IOMMUS and nr_iommus) for a later patch. --- a/xen/drivers/passthrough/vtd/iommu.c +++ b/xen/drivers/passthrough/vtd/iommu.c @@ -1168,10 +1168,10 @@ int __init iommu_alloc(struct acpi_drhd_ unsigned long sagaw, nr_dom; int agaw; - if ( nr_iommus > MAX_IOMMUS ) + if ( nr_iommus >= MAX_IOMMUS ) { dprintk(XENLOG_ERR VTDPREFIX, - "IOMMU: nr_iommus %d > MAX_IOMMUS\n", nr_iommus); + "IOMMU: nr_iommus %d > MAX_IOMMUS\n", nr_iommus + 1); return -ENOMEM; }