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=-5.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 D6327C2D0DB for ; Fri, 24 Jan 2020 14:36:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A8006206F0 for ; Fri, 24 Jan 2020 14:36:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731652AbgAXOgw (ORCPT ); Fri, 24 Jan 2020 09:36:52 -0500 Received: from 8bytes.org ([81.169.241.247]:60812 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731450AbgAXOgu (ORCPT ); Fri, 24 Jan 2020 09:36:50 -0500 Received: by theia.8bytes.org (Postfix, from userid 1000) id 97D33A52; Fri, 24 Jan 2020 15:36:49 +0100 (CET) Date: Fri, 24 Jan 2020 15:36:48 +0100 From: Joerg Roedel To: Lu Baolu Cc: ashok.raj@intel.com, jacob.jun.pan@intel.com, kevin.tian@intel.com, iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/1] iommu/vt-d: Remove unnecessary WARN_ON_ONCE() Message-ID: <20200124143648.GC27081@8bytes.org> References: <20200116015236.4458-1-baolu.lu@linux.intel.com> <20200117095953.GB15760@8bytes.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Jan 18, 2020 at 10:14:11AM +0800, Lu Baolu wrote: > Hi Joerg, > > On 1/17/20 5:59 PM, Joerg Roedel wrote: > > On Thu, Jan 16, 2020 at 09:52:36AM +0800, Lu Baolu wrote: > > > Address field in device TLB invalidation descriptor is qualified > > > by the S field. If S field is zero, a single page at page address > > > specified by address [63:12] is requested to be invalidated. If S > > > field is set, the least significant bit in the address field with > > > value 0b (say bit N) indicates the invalidation address range. The > > > spec doesn't require the address [N - 1, 0] to be cleared, hence > > > remove the unnecessary WARN_ON_ONCE(). > > > > > > Otherwise, the caller might set "mask = MAX_AGAW_PFN_WIDTH" in order > > > to invalidating all the cached mappings on an endpoint, and below > > > overflow error will be triggered. > > > > > > [...] > > > UBSAN: Undefined behaviour in drivers/iommu/dmar.c:1354:3 > > > shift exponent 64 is too large for 64-bit type 'long long unsigned int' > > > [...] > > > > > > Reported-and-tested-by: Frank > > > Signed-off-by: Lu Baolu > > > > Does this need a Fixes and/or stable tag? > > > > This doesn't cause any errors, just an unnecessary checking of > > "0 & ((1UL << 64) - 1)" > > in some cases. Okay, applied for v5.6. 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=-5.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 4ADF9C2D0DB for ; Fri, 24 Jan 2020 14:36:57 +0000 (UTC) Received: from silver.osuosl.org (smtp3.osuosl.org [140.211.166.136]) (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 17434206F0 for ; Fri, 24 Jan 2020 14:36:56 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 17434206F0 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=8bytes.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by silver.osuosl.org (Postfix) with ESMTP id E0F0120494; Fri, 24 Jan 2020 14:36:56 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from silver.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id DvYbTbyrZUEI; Fri, 24 Jan 2020 14:36:55 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by silver.osuosl.org (Postfix) with ESMTP id 9B34D203EE; Fri, 24 Jan 2020 14:36:55 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 7A609C18DD; Fri, 24 Jan 2020 14:36:55 +0000 (UTC) Received: from hemlock.osuosl.org (smtp2.osuosl.org [140.211.166.133]) by lists.linuxfoundation.org (Postfix) with ESMTP id 23680C0174 for ; Fri, 24 Jan 2020 14:36:53 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by hemlock.osuosl.org (Postfix) with ESMTP id 0ED0E883B0 for ; Fri, 24 Jan 2020 14:36:53 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from hemlock.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id KvK247MRjBKO for ; Fri, 24 Jan 2020 14:36:51 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from theia.8bytes.org (8bytes.org [81.169.241.247]) by hemlock.osuosl.org (Postfix) with ESMTPS id 9B460883A6 for ; Fri, 24 Jan 2020 14:36:51 +0000 (UTC) Received: by theia.8bytes.org (Postfix, from userid 1000) id 97D33A52; Fri, 24 Jan 2020 15:36:49 +0100 (CET) Date: Fri, 24 Jan 2020 15:36:48 +0100 From: Joerg Roedel To: Lu Baolu Subject: Re: [PATCH 1/1] iommu/vt-d: Remove unnecessary WARN_ON_ONCE() Message-ID: <20200124143648.GC27081@8bytes.org> References: <20200116015236.4458-1-baolu.lu@linux.intel.com> <20200117095953.GB15760@8bytes.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Cc: linux-kernel@vger.kernel.org, kevin.tian@intel.com, ashok.raj@intel.com, iommu@lists.linux-foundation.org, jacob.jun.pan@intel.com X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" On Sat, Jan 18, 2020 at 10:14:11AM +0800, Lu Baolu wrote: > Hi Joerg, > > On 1/17/20 5:59 PM, Joerg Roedel wrote: > > On Thu, Jan 16, 2020 at 09:52:36AM +0800, Lu Baolu wrote: > > > Address field in device TLB invalidation descriptor is qualified > > > by the S field. If S field is zero, a single page at page address > > > specified by address [63:12] is requested to be invalidated. If S > > > field is set, the least significant bit in the address field with > > > value 0b (say bit N) indicates the invalidation address range. The > > > spec doesn't require the address [N - 1, 0] to be cleared, hence > > > remove the unnecessary WARN_ON_ONCE(). > > > > > > Otherwise, the caller might set "mask = MAX_AGAW_PFN_WIDTH" in order > > > to invalidating all the cached mappings on an endpoint, and below > > > overflow error will be triggered. > > > > > > [...] > > > UBSAN: Undefined behaviour in drivers/iommu/dmar.c:1354:3 > > > shift exponent 64 is too large for 64-bit type 'long long unsigned int' > > > [...] > > > > > > Reported-and-tested-by: Frank > > > Signed-off-by: Lu Baolu > > > > Does this need a Fixes and/or stable tag? > > > > This doesn't cause any errors, just an unnecessary checking of > > "0 & ((1UL << 64) - 1)" > > in some cases. Okay, applied for v5.6. _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu