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_PASS,URIBL_BLOCKED,USER_AGENT_MUTT 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 EEFADECE561 for ; Thu, 20 Sep 2018 06:54:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B3FBA2083A for ; Thu, 20 Sep 2018 06:54:32 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B3FBA2083A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731320AbeITMg0 (ORCPT ); Thu, 20 Sep 2018 08:36:26 -0400 Received: from verein.lst.de ([213.95.11.211]:57950 "EHLO newverein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726193AbeITMgZ (ORCPT ); Thu, 20 Sep 2018 08:36:25 -0400 Received: by newverein.lst.de (Postfix, from userid 2407) id DF52168D7F; Thu, 20 Sep 2018 08:54:30 +0200 (CEST) Date: Thu, 20 Sep 2018 08:54:30 +0200 From: Christoph Hellwig To: Marek Szyprowski Cc: zhe.he@windriver.com, hch@lst.de, robin.murphy@arm.com, iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] kernel/dma: Fix panic caused by passing cma to command line Message-ID: <20180920065430.GA13761@lst.de> References: <1537154660-296740-1-git-send-email-zhe.he@windriver.com> <20180918092834eucas1p1ebdbc3051a7ca8bbacec26b955689784~VdHnT_5yZ0331203312eucas1p1U@eucas1p1.samsung.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180918092834eucas1p1ebdbc3051a7ca8bbacec26b955689784~VdHnT_5yZ0331203312eucas1p1U@eucas1p1.samsung.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 Tue, Sep 18, 2018 at 11:28:33AM +0200, Marek Szyprowski wrote: > Hi > > On 2018-09-17 05:24, zhe.he@windriver.com wrote: > > From: He Zhe > > > > early_cma does not check input argument before passing it to > > simple_strtoull. The argument would be a NULL pointer if "cma", without > > its value, is set in command line and thus causes the following panic. > > > > PANIC: early exception 0xe3 IP 10:ffffffffa3e9db8d error 0 cr2 0x0 > > [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 4.19.0-rc3-yocto-standard+ #7 > > [ 0.000000] RIP: 0010:_parse_integer_fixup_radix+0xd/0x70 > > ... > > [ 0.000000] Call Trace: > > [ 0.000000] simple_strtoull+0x29/0x70 > > [ 0.000000] memparse+0x26/0x90 > > [ 0.000000] early_cma+0x17/0x6a > > [ 0.000000] do_early_param+0x57/0x8e > > [ 0.000000] parse_args+0x208/0x320 > > [ 0.000000] ? rdinit_setup+0x30/0x30 > > [ 0.000000] parse_early_options+0x29/0x2d > > [ 0.000000] ? rdinit_setup+0x30/0x30 > > [ 0.000000] parse_early_param+0x36/0x4d > > [ 0.000000] setup_arch+0x336/0x99e > > [ 0.000000] start_kernel+0x6f/0x4e6 > > [ 0.000000] x86_64_start_reservations+0x24/0x26 > > [ 0.000000] x86_64_start_kernel+0x6f/0x72 > > [ 0.000000] secondary_startup_64+0xa4/0xb0 > > > > This patch adds a check to prevent the panic. > > > > Signed-off-by: He Zhe > > Cc: stable@vger.kernel.org > > Cc: hch@lst.de > > Cc: m.szyprowski@samsung.com > > Cc: robin.murphy@arm.com > > Thanks for the fix. > > Reviewed-by: Marek Szyprowski Thanks, added to the dma-mapping tree.