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=-13.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 B54E2C433F8 for ; Tue, 14 Jul 2020 19:11:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8C17B22507 for ; Tue, 14 Jul 2020 19:11:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1594753892; bh=t14ieBLjcRC8mGAiZegb7Cr7kUc2KlBM9DA1w+vutoM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=tqs1Wi0V4CRnLDNXp9hXGjLp0z8j58upmpxbrkplVwdieIOT44dC6Ia7sUS0ATOE6 6TqnJCj2TCFsfllVkym+7IuVulTmJ3u4u+lBS1ewRCr8mRZg2uUejlIiPxF4fnPS5q iC8k4IM18VqQTVtUFc49o/Q4RIpcAZWwZ/Z54xVI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729610AbgGNStE (ORCPT ); Tue, 14 Jul 2020 14:49:04 -0400 Received: from mail.kernel.org ([198.145.29.99]:44694 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730047AbgGNStA (ORCPT ); Tue, 14 Jul 2020 14:49:00 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 0365C22AAA; Tue, 14 Jul 2020 18:48:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1594752539; bh=t14ieBLjcRC8mGAiZegb7Cr7kUc2KlBM9DA1w+vutoM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lZrATEcO99ER/+SCPMZVXiZ/QVk9nngnw3Gt0iHorDy+vsXzpjvi3T0wQTVM9agJF Kfb3cmfBEhCWBfZMNnRnr4oPRH4FVDNzdYIEflQNS3VQvc3GTtdTLATVMclBqKpUzG k88tI8QxKT8NaW/iWirEX2TJWzX6SV4JNq6qj1y4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Xiyu Yang , Xin Tan , =?UTF-8?q?Christian=20K=C3=B6nig?= , Sasha Levin Subject: [PATCH 5.4 008/109] drm/ttm: Fix dma_fence refcnt leak when adding move fence Date: Tue, 14 Jul 2020 20:43:11 +0200 Message-Id: <20200714184105.922884512@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714184105.507384017@linuxfoundation.org> References: <20200714184105.507384017@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Xiyu Yang [ Upstream commit 11425c4519e2c974a100fc984867046d905b9380 ] 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-by: Christian König Link: https://patchwork.freedesktop.org/patch/370221/ Signed-off-by: Christian König Signed-off-by: Sasha Levin --- 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 abf165b2f64fc..3ce8ad7603c7f 100644 --- a/drivers/gpu/drm/ttm/ttm_bo.c +++ b/drivers/gpu/drm/ttm/ttm_bo.c @@ -941,8 +941,10 @@ 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); -- 2.25.1