From patchwork Sat Mar 19 02:21:42 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhang Qilong X-Patchwork-Id: 12786045 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 53C03C433F5 for ; Sat, 19 Mar 2022 02:22:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234956AbiCSCXX (ORCPT ); Fri, 18 Mar 2022 22:23:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60608 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241819AbiCSCXW (ORCPT ); Fri, 18 Mar 2022 22:23:22 -0400 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A7A90278573 for ; Fri, 18 Mar 2022 19:22:01 -0700 (PDT) Received: from kwepemi500021.china.huawei.com (unknown [172.30.72.56]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4KL4Mt35gvzCqlx; Sat, 19 Mar 2022 10:19:54 +0800 (CST) Received: from kwepemm600014.china.huawei.com (7.193.23.54) by kwepemi500021.china.huawei.com (7.221.188.245) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Sat, 19 Mar 2022 10:21:57 +0800 Received: from huawei.com (10.90.53.225) by kwepemm600014.china.huawei.com (7.193.23.54) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Sat, 19 Mar 2022 10:21:57 +0800 From: Zhang Qilong To: , , , CC: , Subject: [PATCH -next v2] dmaengine: mediatek:Fix PM usage reference leak of mtk_uart_apdma_alloc_chan_resources Date: Sat, 19 Mar 2022 10:21:42 +0800 Message-ID: <20220319022142.142709-1-zhangqilong3@huawei.com> X-Mailer: git-send-email 2.26.0.106.g9fadedd MIME-Version: 1.0 X-Originating-IP: [10.90.53.225] X-ClientProxiedBy: dggems705-chm.china.huawei.com (10.3.19.182) To kwepemm600014.china.huawei.com (7.193.23.54) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org From: zhangqilong pm_runtime_get_sync will increment pm usage counter even it failed. Forgetting to putting operation will result in reference leak here. We fix it: 1) Replacing it with pm_runtime_resume_and_get to keep usage counter balanced. 2) Add putting operation before returning error. Fixes:9135408c3ace4 ("dmaengine: mediatek: Add MediaTek UART APDMA support") Signed-off-by: Zhang Qilong --- v2: - Fix misleadin commit message. --- drivers/dma/mediatek/mtk-uart-apdma.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/dma/mediatek/mtk-uart-apdma.c b/drivers/dma/mediatek/mtk-uart-apdma.c index 375e7e647df6..a1517ef1f4a0 100644 --- a/drivers/dma/mediatek/mtk-uart-apdma.c +++ b/drivers/dma/mediatek/mtk-uart-apdma.c @@ -274,7 +274,7 @@ static int mtk_uart_apdma_alloc_chan_resources(struct dma_chan *chan) unsigned int status; int ret; - ret = pm_runtime_get_sync(mtkd->ddev.dev); + ret = pm_runtime_resume_and_get(mtkd->ddev.dev); if (ret < 0) { pm_runtime_put_noidle(chan->device->dev); return ret; @@ -288,18 +288,21 @@ static int mtk_uart_apdma_alloc_chan_resources(struct dma_chan *chan) ret = readx_poll_timeout(readl, c->base + VFF_EN, status, !status, 10, 100); if (ret) - return ret; + goto err_pm; ret = request_irq(c->irq, mtk_uart_apdma_irq_handler, IRQF_TRIGGER_NONE, KBUILD_MODNAME, chan); if (ret < 0) { dev_err(chan->device->dev, "Can't request dma IRQ\n"); - return -EINVAL; + ret = -EINVAL; + goto err_pm; } if (mtkd->support_33bits) mtk_uart_apdma_write(c, VFF_4G_SUPPORT, VFF_4G_SUPPORT_CLR_B); +err_pm: + pm_runtime_put_noidle(mtkd->ddev.dev); return ret; }