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=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 5BEB6C433E0 for ; Thu, 2 Jul 2020 01:23:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 28A522082F for ; Thu, 2 Jul 2020 01:23:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593652990; bh=H6E1ErTHKdU8VDL/lt494z9m+g1stL2ziOwVXwpMVPw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=bOJ4fld14RBMSMCVVQgYmRJxX6XQ5yNAfS477uHoGAWRH/wHT+ns6qQjGIs8ya/Xk iQgIpTkG0uoePb2WKCm3kocjfWCko5F/rFGYxI7OIn7HRgIjZq+AnlE4wbA8I7sTTB UvxKmVkwMNRU6d4Coe3qqJxc/JLplcmq9UJeScR8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728218AbgGBBXJ (ORCPT ); Wed, 1 Jul 2020 21:23:09 -0400 Received: from mail.kernel.org ([198.145.29.99]:53346 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728174AbgGBBXD (ORCPT ); Wed, 1 Jul 2020 21:23:03 -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 8AAAA20874; Thu, 2 Jul 2020 01:23:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593652982; bh=H6E1ErTHKdU8VDL/lt494z9m+g1stL2ziOwVXwpMVPw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RsBmcNxWvcFx8Qd0eTxU8HcHpfbmrYWP3whfaXxMqJJgJ/fIVfN4kC5Vr8OjHGNI7 8v5eCp5xz1u9XkDTBf34C1IvnEhRySFyBksWYTJf9cLV1A6IK+qGgDjNdKARoB0bnx C6g3FlX7XZ9dxdLqx5fQ05/xOz5esjdVUEQCnXh8= 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 5.7 06/53] drm/ttm: Fix dma_fence refcnt leak in ttm_bo_vm_fault_reserved Date: Wed, 1 Jul 2020 21:21:15 -0400 Message-Id: <20200702012202.2700645-6-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200702012202.2700645-1-sashal@kernel.org> References: <20200702012202.2700645-1-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: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Xiyu Yang [ Upstream commit 37cc4b95d13f311c04aa8e9daacca3905ad45ca7 ] ttm_bo_vm_fault_reserved() invokes dma_fence_get(), which returns a reference of the specified dma_fence object to "moving" with increased refcnt. When ttm_bo_vm_fault_reserved() returns, local variable "moving" becomes invalid, so the refcount should be decreased to keep refcount balanced. The reference counting issue happens in several exception handling paths of ttm_bo_vm_fault_reserved(). When those error scenarios occur such as "err" equals to -EBUSY, 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/370219/ Signed-off-by: Christian König Signed-off-by: Sasha Levin --- drivers/gpu/drm/ttm/ttm_bo_vm.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c index 0ad30b1129821..72100b84c7a90 100644 --- a/drivers/gpu/drm/ttm/ttm_bo_vm.c +++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c @@ -300,8 +300,10 @@ vm_fault_t ttm_bo_vm_fault_reserved(struct vm_fault *vmf, break; case -EBUSY: case -ERESTARTSYS: + dma_fence_put(moving); return VM_FAULT_NOPAGE; default: + dma_fence_put(moving); return VM_FAULT_SIGBUS; } -- 2.25.1