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spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=5bEDcPL7Ximf3V6oWwhwhN/3knuQiH6PfrNhK6997Iw=; b=gFLpo9zr8OkAqU K5KI8n6xgyxlwQuiEj/07ELch8EWYUlBRGyZLM1IX7lBb8i5J59ZObJ15hAJnc6qmdI5B7ycZLQbt dCSh4c+uNZyniL2Jo2WDJL/qaQLYkZfNYkLk+vmvlGWF9OBqRoP2NsVC3ldjA5JmidXL/N8p3qPiL 6zqgOI3R4o32sfeTmAWXNLvkM7Q24CAmOjo07PmztkE86T17N/ToVjpAw256io1C+N7eP1Wo5v4Wm 9KyAUQNFRgU+wxh9JA9b5bibrc5L6IWxe51EwVOqZ+SAilutnxegw0smPfM2EanQQGTOhjWbSA5Bg 3KSU9hhEwcV26s4rTqXw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1lqCes-003059-7O; Mon, 07 Jun 2021 10:39:03 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1lqCLh-002rCl-RO for linux-arm-kernel@lists.infradead.org; Mon, 07 Jun 2021 10:19:15 +0000 Received: by mail.kernel.org (Postfix) with ESMTPSA id 728CB6108C; Mon, 7 Jun 2021 10:19:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1623061153; bh=VTXaUpTsvgBICiL2lKaVnHTXuZH2cZNa6FWeUX+IisE=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=RVVTU06jgeAsSo/v/fEAlG1xId7qFWDasaTznd2qQ64Uk30/NJbygYrmH4HWiWaou Nx9OEPtvZlVibiqfpvZU8qf2uIp7A/lSu+BaSGZHU0V1ky2KF3nK24EJix6mir/gkm M5OuKTah7QnercdV/DgyniAVxs5A+4BkYGy6BI/CtHTsdlcO9n5EnmH7Z87tsoTMHL QjpmLdSzV4/7F/ruljRn9IflXQA4J6+rfnM8SZwX2UZv5Uj2wd+PVTRAXd8uo8537i chhMxB+tdfdxIMdeh2+gRz7+jrcEIO+A8a6w1d9t7insDVjhZWJJ3HHSJDtS7G9f7Z GR8wQQl1SVUcQ== Date: Mon, 7 Jun 2021 15:49:09 +0530 From: Vinod Koul To: Johan Hovold Cc: "yukuai (C)" , 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-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210607_031913_941016_3AFE986C X-CRM114-Status: GOOD ( 16.67 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel