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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no 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 5EB9CC76190 for ; Mon, 22 Jul 2019 11:43:15 +0000 (UTC) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org [140.211.169.12]) (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 334F621921 for ; Mon, 22 Jul 2019 11:43:15 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 334F621921 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from mail.linux-foundation.org (localhost [127.0.0.1]) by mail.linuxfoundation.org (Postfix) with ESMTP id DEA44CAE; Mon, 22 Jul 2019 11:43:14 +0000 (UTC) Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 3E64DCAC for ; Mon, 22 Jul 2019 11:43:14 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id E2BEEFE for ; Mon, 22 Jul 2019 11:43:05 +0000 (UTC) Received: by verein.lst.de (Postfix, from userid 2407) id E6A1868B20; Mon, 22 Jul 2019 13:43:03 +0200 (CEST) Date: Mon, 22 Jul 2019 13:43:03 +0200 From: Christoph Hellwig To: Eric Auger Subject: Re: [PATCH] dma-mapping: Protect dma_addressing_limited against NULL dma_mask Message-ID: <20190722114303.GA32052@lst.de> References: <20190722111449.29258-1-eric.auger@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20190722111449.29258-1-eric.auger@redhat.com> User-Agent: Mutt/1.5.17 (2007-11-01) Cc: linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, eric.auger.pro@gmail.com, robin.murphy@arm.com, hch@lst.de X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.12 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 Sender: iommu-bounces@lists.linux-foundation.org Errors-To: iommu-bounces@lists.linux-foundation.org I posted a fix that takes care of this in SCSI this morning: https://marc.info/?l=linux-scsi&m=156378725427719&w=2 I suspect for virtio-blk we should do the same. > static inline bool dma_addressing_limited(struct device *dev) > { > - return min_not_zero(*dev->dma_mask, dev->bus_dma_mask) < > - dma_get_required_mask(dev); > + return dev->dma_mask ? min_not_zero(*dev->dma_mask, dev->bus_dma_mask) < > + dma_get_required_mask(dev) : false; But to be on the safe side we could still do an early return here, but it should have a WARN_ON_ONCE. _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu