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=-2.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,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 54509C433E1 for ; Wed, 20 May 2020 09:01:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2F08D2075F for ; Wed, 20 May 2020 09:01:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com header.b="UsNiCfJx" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726875AbgETJBK (ORCPT ); Wed, 20 May 2020 05:01:10 -0400 Received: from lelv0142.ext.ti.com ([198.47.23.249]:52030 "EHLO lelv0142.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726403AbgETJBI (ORCPT ); Wed, 20 May 2020 05:01:08 -0400 Received: from lelv0265.itg.ti.com ([10.180.67.224]) by lelv0142.ext.ti.com (8.15.2/8.15.2) with ESMTP id 04K914TP015260; Wed, 20 May 2020 04:01:04 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1589965264; bh=b6H804B8RuHsNLb8km9T/gbWP07ThkPpda0h3OTyzoI=; h=To:From:Subject:Date; b=UsNiCfJx9jxEloq1ipY1C1pu6wXYHddi64OvWR3WAcrvcXcXFnkFu9GTtC/Kzpa6K qkYk/tUy33g81V97gqPUs0js5XTUkkhz1makmv+CVtZxhwVttx04iEUwhdiqyPVK+r aN4xHHCiX556f4fWLCopTGT/j1wg+d4Zm7NE6OdM= Received: from DLEE100.ent.ti.com (dlee100.ent.ti.com [157.170.170.30]) by lelv0265.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 04K9147c085736 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Wed, 20 May 2020 04:01:04 -0500 Received: from DLEE111.ent.ti.com (157.170.170.22) by DLEE100.ent.ti.com (157.170.170.30) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1979.3; Wed, 20 May 2020 04:00:15 -0500 Received: from fllv0039.itg.ti.com (10.64.41.19) by DLEE111.ent.ti.com (157.170.170.22) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1979.3 via Frontend Transport; Wed, 20 May 2020 04:00:15 -0500 Received: from [192.168.2.6] (ileax41-snat.itg.ti.com [10.172.224.153]) by fllv0039.itg.ti.com (8.15.2/8.15.2) with ESMTP id 04K90EGS035997; Wed, 20 May 2020 04:00:14 -0500 To: Linux Media Mailing List , Mauro Carvalho Chehab , Ulf Hansson , Marek Szyprowski , LKML From: Tomi Valkeinen Subject: Bad kfree of dma_parms in v5.7-rc5 Message-ID: Date: Wed, 20 May 2020 12:00:14 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.7.0 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8"; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, Commit 9495b7e92f716ab2bd6814fab5e97ab4a39adfdd ("driver core: platform: Initialize dma_parms for platform devices") v5.7-rc5 causes at least some v4l2 platform drivers to break when freeing resources. E.g. drivers/media/platform/ti-vpe/cal.c uses vb2_dma_contig_set_max_seg_size() and vb2_dma_contig_clear_max_seg_size() to manage the dma_params, and similar pattern is seen in other drivers too. After 9495b7e92f716ab2, vb2_dma_contig_set_max_seg_size() will not allocate anything, but vb2_dma_contig_clear_max_seg_size() will still kfree the dma_params. I'm not sure what's the proper fix here. A flag somewhere to indicate that vb2_dma_contig_set_max_seg_size() did allocate, and thus vb2_dma_contig_clear_max_seg_size() must free? Or drop the kzalloc and kfree totally, if dma_params is now supposed to always be there? Or revert 9495b7e92f716ab2, as it was added so late? Tomi -- Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki