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=-8.2 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MSGID_FROM_MTA_HEADER,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 BED89C433E2 for ; Mon, 15 Jun 2020 08:55:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 916AF20663 for ; Mon, 15 Jun 2020 08:55:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=amdcloud.onmicrosoft.com header.i=@amdcloud.onmicrosoft.com header.b="PWTUPyRS" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729261AbgFOIzh (ORCPT ); Mon, 15 Jun 2020 04:55:37 -0400 Received: from mail-dm6nam11on2066.outbound.protection.outlook.com ([40.107.223.66]:1249 "EHLO NAM11-DM6-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728526AbgFOIzg (ORCPT ); Mon, 15 Jun 2020 04:55:36 -0400 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=k0teWHyDYueGlf0t0mFdTjuzHoGJ81lJo8ham9LGEd4lrhG/WhsIWl/BNokeTkqS+HdEvoiDTkCfUYlhu4js14E0AjN/flKXcGZ93vGI2YQ+/EqWNZq2HX58xcG+dDM/VgpPCDFv5IIo1ILUrsIle3hWjeaTvlAyz5EAJFKKCv5j76fAg6dljALG2HCifapT1Y0rjE8bE+2Y7HE7Styabvj/b338GKPM0UuI7cyIDAjBhOtddfk8KAUZleWOd+t9qzEIHrGM0Tdi44nm2i3XUzxZ7noXR2J4LAGkyxy0fRrxVyaj6sBiAVOB2a+hzAFj0N52Sgn0ThuWmGeT/nBQ2g== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=caso4/0QK0RPuLPY5+h88j14LzivqNpQK+t8n+09m0M=; b=hSVyUyCzJazkYwWOGfNtcZl4lYGsqUUPmcp310vJhDNFlqd9zFwbkpDn8NA/WWEOAOifUtjY8Hbp0g/15noDVwXhIAZHPQrVCcIgiEk69siSsTu/ebYgLMQOH8/9x4nFlznW0qw8JG73IjUlyN3ky2agZ2kkhbYq1r6bzHT1WW/UvfkywVCd/VKQtScPVAW5oOcGQ19n0xH5oOXb+LMNFkhWuPj6EXP+nyldDOxVBWdzKluNHYzcW2A6Dk3t1QaPag767wTgaeG1VFk9lZwKdEZBC8QPZiLiMpEAXDcpIWHfkFx0EZhp/ymC6U5B8ivUDKzKj+x79gzvkRahkefq6Q== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=amd.com; dmarc=pass action=none header.from=amd.com; dkim=pass header.d=amd.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amdcloud.onmicrosoft.com; s=selector2-amdcloud-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=caso4/0QK0RPuLPY5+h88j14LzivqNpQK+t8n+09m0M=; b=PWTUPyRS2AMrkUdYzFVuPCP3BsiPCcsMALJ1hLTd2Dr12EZ3lzLhHvMyrMXXOknoWdEpVDhHMmt93kfYu0eifosIGuTLXM9WpzcK0PZ1xX9ZcitTj39i0lGV+debw89bz+mvym2c6EYkZZJ6x+6vDDMzqvcyfHcwXjuXGX5ZxWg= Authentication-Results: gmail.com; dkim=none (message not signed) header.d=none;gmail.com; dmarc=none action=none header.from=amd.com; Received: from DM6PR12MB4401.namprd12.prod.outlook.com (2603:10b6:5:2a9::15) by DM6PR12MB3785.namprd12.prod.outlook.com (2603:10b6:5:1cd::18) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3088.18; Mon, 15 Jun 2020 08:55:33 +0000 Received: from DM6PR12MB4401.namprd12.prod.outlook.com ([fe80::7949:b580:a2d5:f766]) by DM6PR12MB4401.namprd12.prod.outlook.com ([fe80::7949:b580:a2d5:f766%3]) with mapi id 15.20.3088.029; Mon, 15 Jun 2020 08:55:33 +0000 Subject: Re: [PATCH] drm/ttm: Fix dma_fence refcnt leak when adding move fence To: Xiyu Yang , Huang Rui , David Airlie , Daniel Vetter , Sumit Semwal , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, linaro-mm-sig@lists.linaro.org Cc: yuanxzhang@fudan.edu.cn, kjlu@umn.edu, Xin Tan References: <1592051425-94019-1-git-send-email-xiyuyang19@fudan.edu.cn> From: =?UTF-8?Q?Christian_K=c3=b6nig?= Message-ID: Date: Mon, 15 Jun 2020 10:55:25 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 In-Reply-To: <1592051425-94019-1-git-send-email-xiyuyang19@fudan.edu.cn> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US X-ClientProxiedBy: AM4PR0701CA0013.eurprd07.prod.outlook.com (2603:10a6:200:42::23) To DM6PR12MB4401.namprd12.prod.outlook.com (2603:10b6:5:2a9::15) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 Received: from [IPv6:2a02:908:1252:fb60:be8a:bd56:1f94:86e7] (2a02:908:1252:fb60:be8a:bd56:1f94:86e7) by AM4PR0701CA0013.eurprd07.prod.outlook.com (2603:10a6:200:42::23) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3109.10 via Frontend Transport; Mon, 15 Jun 2020 08:55:30 +0000 X-Originating-IP: [2a02:908:1252:fb60:be8a:bd56:1f94:86e7] X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-HT: Tenant X-MS-Office365-Filtering-Correlation-Id: 324310e7-c417-4957-6984-08d81109dcc7 X-MS-TrafficTypeDiagnostic: DM6PR12MB3785: X-MS-Exchange-Transport-Forked: True X-Microsoft-Antispam-PRVS: X-MS-Oob-TLC-OOBClassifiers: OLM:7691; X-Forefront-PRVS: 04359FAD81 X-MS-Exchange-SenderADCheck: 1 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: einueZtfa2o2jawHASqsHuWa2SPlE8Q5HYxJ3e0BtS0E6gkP4Yy/R4V0d9jFVXSzrqARCDb7W0zeTXzj9OKOCx/dLZ88mehukY7KMgM0NmxeoHSLSSoT0oZzupaP+A0i6yFyw6Ai8H3bE/6lR5W/HhARvX/hRtswd8lmHsIQZO2Ty+nMgrkTqIkTdBOOOP5ViYGaqBR7X6G3TB6yh2bvsly1yRstZD+tCXe9DwQo6etd2HzsSmPBnHTcabLPntHg4xv6onkPVVEEZCtFqcoHsR6mKL68lI2Mt7jkoVmSd97TF+Q8+w730CyquceL4iwlFZX0CoA/IreJZA08xL5u4MuSDHPZWYLRc66q7fv06Cin/0dafoOUvBCPXwLmfykJ X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:DM6PR12MB4401.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFTY:;SFS:(4636009)(366004)(39860400002)(346002)(136003)(396003)(376002)(8676002)(83380400001)(7416002)(5660300002)(6666004)(110136005)(478600001)(8936002)(4326008)(186003)(16526019)(2906002)(316002)(36756003)(66946007)(66476007)(66556008)(86362001)(31686004)(52116002)(31696002)(2616005)(6486002)(43740500002);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData: 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 X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-Network-Message-Id: 324310e7-c417-4957-6984-08d81109dcc7 X-MS-Exchange-CrossTenant-OriginalArrivalTime: 15 Jun 2020 08:55:33.1828 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: bC/pRgeG32uym8YMMNDiDyexG8BJy5UTETC8bZXuIgTcYekST6FGxqH4uYcGDqq1 X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM6PR12MB3785 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am 13.06.20 um 14:30 schrieb Xiyu Yang: > ttm_bo_add_move_fence() invokes dma_fence_get(), which returns a > reference of the specified dma_fence object to "fence" with increased > refcnt. > > When ttm_bo_add_move_fence() returns, local variable "fence" becomes > invalid, so the refcount should be decreased to keep refcount balanced. > > The reference counting issue happens in one exception handling path of > ttm_bo_add_move_fence(). When no_wait_gpu flag is equals to true, the > function forgets to decrease the refcnt increased by dma_fence_get(), > causing a refcnt leak. > > Fix this issue by calling dma_fence_put() when no_wait_gpu flag is > equals to true. > > Signed-off-by: Xiyu Yang > Signed-off-by: Xin Tan Reviewed and pushed this one as well as the other ttm fix to drm-misc-fixes. That should show up in Linus tree rather soon. Thanks for the help, Christian. PS: Are you working on some new automated scripts to catch that stuff or how did you stumbled over it? > --- > drivers/gpu/drm/ttm/ttm_bo.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c > index f73b81c2576e..0f20e14a4cfd 100644 > --- a/drivers/gpu/drm/ttm/ttm_bo.c > +++ b/drivers/gpu/drm/ttm/ttm_bo.c > @@ -883,8 +883,10 @@ static int ttm_bo_add_move_fence(struct ttm_buffer_object *bo, > if (!fence) > return 0; > > - if (no_wait_gpu) > + if (no_wait_gpu) { > + dma_fence_put(fence); > return -EBUSY; > + } > > dma_resv_add_shared_fence(bo->base.resv, fence); >