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 A8658C7618B for ; Tue, 23 Jul 2019 15:37:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 83E542239F for ; Tue, 23 Jul 2019 15:37:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387887AbfGWPhl (ORCPT ); Tue, 23 Jul 2019 11:37:41 -0400 Received: from verein.lst.de ([213.95.11.211]:42762 "EHLO verein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727733AbfGWPhk (ORCPT ); Tue, 23 Jul 2019 11:37:40 -0400 Received: by verein.lst.de (Postfix, from userid 2407) id 56C4968B02; Tue, 23 Jul 2019 17:37:39 +0200 (CEST) Date: Tue, 23 Jul 2019 17:37:39 +0200 From: Christoph Hellwig To: Auger Eric Cc: eric.auger.pro@gmail.com, hch@lst.de, m.szyprowski@samsung.com, robin.murphy@arm.com, mst@redhat.com, jasowang@redhat.com, virtualization@lists.linux-foundation.org, iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] dma-mapping: Use dma_get_mask in dma_addressing_limited Message-ID: <20190723153739.GC720@lst.de> References: <20190722165149.3763-1-eric.auger@redhat.com> <77ba1061-08b6-421e-a6dd-d5db9851325b@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <77ba1061-08b6-421e-a6dd-d5db9851325b@redhat.com> User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jul 22, 2019 at 06:56:49PM +0200, Auger Eric wrote: > Hi Christoph, > > On 7/22/19 6:51 PM, Eric Auger wrote: > > We currently have cases where the dma_addressing_limited() gets > > called with dma_mask unset. This causes a NULL pointer dereference. > > > > Use dma_get_mask() accessor to prevent the crash. > > > > Fixes: b866455423e0 ("dma-mapping: add a dma_addressing_limited helper") > > Signed-off-by: Eric Auger > > As a follow-up of my last email, here is a patch featuring > dma_get_mask(). But you don't have the WARN_ON_ONCE anymore, pointing > out suspect users. > > Feel free to pick up your preferred approach I can take this for now as we are past the merge window.