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=-5.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,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 11EC4C433DF for ; Tue, 30 Jun 2020 08:43:02 +0000 (UTC) Received: from hemlock.osuosl.org (smtp2.osuosl.org [140.211.166.133]) (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 D70A220768 for ; Tue, 30 Jun 2020 08:43:01 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D70A220768 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 hemlock.osuosl.org (Postfix) with ESMTP id 9336A8835C; Tue, 30 Jun 2020 08:43:01 +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 jfhxEFfbF035; Tue, 30 Jun 2020 08:42:59 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by hemlock.osuosl.org (Postfix) with ESMTP id 9844588359; Tue, 30 Jun 2020 08:42:59 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 6EBFAC088F; Tue, 30 Jun 2020 08:42:59 +0000 (UTC) Received: from hemlock.osuosl.org (smtp2.osuosl.org [140.211.166.133]) by lists.linuxfoundation.org (Postfix) with ESMTP id 55700C016E for ; Tue, 30 Jun 2020 08:42:58 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by hemlock.osuosl.org (Postfix) with ESMTP id 444988835C for ; Tue, 30 Jun 2020 08:42:58 +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 U2pZovGTexjY for ; Tue, 30 Jun 2020 08:42:56 +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 968AA88359 for ; Tue, 30 Jun 2020 08:42:56 +0000 (UTC) Received: by theia.8bytes.org (Postfix, from userid 1000) id E504F26B; Tue, 30 Jun 2020 10:42:52 +0200 (CEST) Date: Tue, 30 Jun 2020 10:42:51 +0200 From: Joerg Roedel To: Robin Murphy Subject: Re: [PATCH] iommu/iova: Don't BUG on invalid PFNs Message-ID: <20200630084251.GA28824@8bytes.org> References: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Cc: iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, Prakash Gupta 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 Tue, Jun 02, 2020 at 02:08:18PM +0100, Robin Murphy wrote: > Unlike the other instances which represent a complete loss of > consistency within the rcache mechanism itself, or a fundamental > and obvious misconfiguration by an IOMMU driver, the BUG_ON() in > iova_magazine_free_pfns() can be provoked at more or less any time > in a "spooky action-at-a-distance" manner by any old device driver > passing nonsense to dma_unmap_*() which then propagates through to > queue_iova(). > > Not only is this well outside the IOVA layer's control, it's also > nowhere near fatal enough to justify panicking anyway - all that > really achieves is to make debugging the offending driver more > difficult. Let's simply WARN and otherwise ignore bogus PFNs. > > Reported-by: Prakash Gupta > Signed-off-by: Robin Murphy > --- > drivers/iommu/iova.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) Applied without stable tag, thanks. _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu