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=-7.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no 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 70597C07E9B for ; Tue, 6 Jul 2021 10:49:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5B97A619CD for ; Tue, 6 Jul 2021 10:49:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231450AbhGFKwe (ORCPT ); Tue, 6 Jul 2021 06:52:34 -0400 Received: from mail.kernel.org ([198.145.29.99]:47438 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231753AbhGFKwc (ORCPT ); Tue, 6 Jul 2021 06:52:32 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 932BE619C3; Tue, 6 Jul 2021 10:49:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1625568594; bh=bPKQG7VMSSD0/w80TXY6qN1X/ZiWRyDZ2D5tRURQYPk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=tA6MLSx4ezUqNV9nz99ni3dC//5IdrSKEZx+qd9oK7btksPTPA9/u8z8D40imzky8 U87OblPdTzumM4K/2ZIrpZ2z8HKk0KPws6PuFQ5a6qRnIjHI6cNSLIm6U3/ri1Pl/j HCjGcaFq6qY6QEHfRJAAorpg2KWXydeaQ26Qs4G9QCpXmFvh8a0mf+XtQdmBb7yK5r DI4KyalVQT43VwBWA9i/EgJijoyoBxs1h0O3H4ybEbCI/bssHcKt1HykaTS0R3vwWo U4Lgu2Hx7nPUrFdKoBOw692vEXKEJKOugPzAAoQEjVzY2JEZFNhRzDPGoVgEA0i/9Q 7vuyU6jH6P6OA== Date: Tue, 6 Jul 2021 16:19:50 +0530 From: Vinod Koul To: "yukuai (C)" Cc: Johan Hovold , mcoquelin.stm32@gmail.com, alexandre.torgue@foss.st.com, michal.simek@xilinx.com, dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, yi.zhang@huawei.com Subject: Re: [PATCH 2/3] dmaengine: usb-dmac: Fix PM reference leak in usb_dmac_probe() Message-ID: References: <20210517081826.1564698-1-yukuai3@huawei.com> <20210517081826.1564698-3-yukuai3@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org On 05-07-21, 16:41, yukuai (C) wrote: > Hi, Vinod > > Are you still intrested in accepting this patch? - Please do not top post - yes, pls rebase and resend > On 2021/06/07 18:19, Vinod Koul wrote: > > On 07-06-21, 10:06, Johan Hovold wrote: > > > On Thu, Jun 03, 2021 at 04:39:08PM +0530, Vinod Koul wrote: > > > > On 31-05-21, 11:19, Johan Hovold wrote: > > > > > On Mon, May 31, 2021 at 02:27:34PM +0530, Vinod Koul wrote: > > > > > > On 31-05-21, 14:11, yukuai (C) wrote: > > > > > > > On 2021/05/31 12:00, Vinod Koul wrote: > > > > > > > > On 17-05-21, 16:18, Yu Kuai wrote: > > > > > > > > > pm_runtime_get_sync will increment pm usage counter even it failed. > > > > > > > > > Forgetting to putting operation will result in reference leak here. > > > > > > > > > Fix it by replacing it with pm_runtime_resume_and_get to keep usage > > > > > > > > > counter balanced. > > > > > > > > > Yes the rumtime_pm is disabled on failure here and the count would have > > > > > > no consequence... > > > > > > > > > > You should still balance the PM usage counter as it isn't reset for > > > > > example when reloading the driver. > > > > > > > > Should I driver trust that on load PM usage counter is balanced and not > > > > to be reset..? > > > > > > Not sure what you're asking here. But a driver should never leave the PM > > > usage counter unbalanced. > > > > Thinking about again, yes we should safely assume the counter is > > balanced when driver loads.. so unloading while balancing sounds better > > behaviour > > > > Thanks > > -- ~Vinod