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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 E13F1C433E2 for ; Thu, 2 Jul 2020 01:34:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C001F2082F for ; Thu, 2 Jul 2020 01:34:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593653691; bh=t14ieBLjcRC8mGAiZegb7Cr7kUc2KlBM9DA1w+vutoM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=xJ0gk0nQx+UdMcmfeGh4BxujxCCQNwX1qSspPy6NI5thHkhu1fN8Q34xrJFEGZfPU 9dRkuZVX39TV3rXp6GliCILIO39NLLdHdOvWw+elMH5xCeaRpl8fDnTN5+FhdROjzc LzZG8wgLdzQ0431fT0+q9l7WIWz+AulkJosPg5zo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728088AbgGBBei (ORCPT ); Wed, 1 Jul 2020 21:34:38 -0400 Received: from mail.kernel.org ([198.145.29.99]:56426 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727917AbgGBBZb (ORCPT ); Wed, 1 Jul 2020 21:25:31 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4868B20884; Thu, 2 Jul 2020 01:25:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593653131; bh=t14ieBLjcRC8mGAiZegb7Cr7kUc2KlBM9DA1w+vutoM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=1oXUp9wzNcRNNnwrckzit2GEfwWFu+UfjWuR9nCt19oi7MXiGAIdU5pz+4bswUwtI j3Z/A7ECNwnqIqUmFzLvit4dJ6ZrQ5KpXfIXdmclBUwKX5HB0XykY8LwVdic0sm9od WV0QX9DlyE0hFD1lbfD5S9J3a9xjciVdSV8f70Vc= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Xiyu Yang , Xin Tan , =?UTF-8?q?Christian=20K=C3=B6nig?= , Sasha Levin , dri-devel@lists.freedesktop.org, linux-media@vger.kernel.org, linaro-mm-sig@lists.linaro.org Subject: [PATCH AUTOSEL 5.4 05/40] drm/ttm: Fix dma_fence refcnt leak when adding move fence Date: Wed, 1 Jul 2020 21:23:26 -0400 Message-Id: <20200702012402.2701121-5-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200702012402.2701121-1-sashal@kernel.org> References: <20200702012402.2701121-1-sashal@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-stable: review X-Patchwork-Hint: Ignore 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