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=-2.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 5C5C2C2BB55 for ; Tue, 7 Apr 2020 14:33:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 05D832072A for ; Tue, 7 Apr 2020 14:33:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="ucXpfMyZ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729197AbgDGOdL (ORCPT ); Tue, 7 Apr 2020 10:33:11 -0400 Received: from mail-pg1-f180.google.com ([209.85.215.180]:37104 "EHLO mail-pg1-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728975AbgDGOdL (ORCPT ); Tue, 7 Apr 2020 10:33:11 -0400 Received: by mail-pg1-f180.google.com with SMTP id r4so1817000pgg.4 for ; Tue, 07 Apr 2020 07:33:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=k3mdrzv8ov6qNww8wQI2y8I8f4cWafSu+jyJH6lIzWQ=; b=ucXpfMyZVUiIB1zisShFYsnfM1jJ70pSDdmoevo5IX4FPFuSCcy5szhQWtqbBylwDh xWj/HM2Q7IKyNo0NtdsK8X2NZzal157uwdff6v22eLC3ZGM+NMcicvLVTx3kD8woc/EP EXiFQAkVsYzUn7gVPJccda5ah5Q8vvtpWIIhq7oMSizR8N9QbQnIVmTnnoF7Zs/YelZd CB4rIwo28flQpMysLQDWaLXcojbeWs1W356L+h1sRuAZyAQN7Tuzlr2MPVOT0Zmz+6EU eiCOkRGSV8qGMiVyFuAjGP4VakWUTPXFGoGZg7PeTVfXh9bT0gqE0Zwokt3QIh2epeJh 44TQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=k3mdrzv8ov6qNww8wQI2y8I8f4cWafSu+jyJH6lIzWQ=; b=WSBy20l/NpvKusCio0YYXVqPrIeQy/b6O7ZO5tGxxo4F66ld7NKhzEQP8FeNPMViCZ gcfXdUlzyef8zJOWm1W9VeC6FumGbctalBqiV+JIfECX/Ync1Zj5hQsHs96T9Yf/denX lQFBU+VtS242wbiswHC0dPmMS8CTCHPGNBuvWUAj2q94fYXtMqwWhjkiGWmQMlHASDUZ Ysc6EgV4R3h+urMXtmMNgN3ghm2AL8XCSTGzhvZza7ykaUH7GgHSl32PbI10haGxNTkL bOsbxqEKSVxeCp2wSRDrdEj6fgasaEHtkZZNTYNGpq5MKS6EGmupQxxIMSJvtjR9VOPp +aCA== X-Gm-Message-State: AGi0PuYYihRsWmQUnNiLQEATDvPFg7PkYoXFYCQ2gccG+3Ts4YA6Ilkp tWC0taLrnN0AGDnnRyoPUCIl X-Google-Smtp-Source: APiQypKxGfjAvQPF8Pqz6aw+byBjxReHnXAvelraYGqfRlAC5VmBFb5x+qvNFukCSMZm1NRD2mr1lQ== X-Received: by 2002:a62:7911:: with SMTP id u17mr2763619pfc.305.1586269989757; Tue, 07 Apr 2020 07:33:09 -0700 (PDT) Received: from Mani-XPS-13-9360 ([2409:4072:6e86:d03b:65ee:cb40:6d79:8376]) by smtp.gmail.com with ESMTPSA id w63sm3922904pgb.5.2020.04.07.07.33.06 (version=TLS1_2 cipher=ECDHE-ECDSA-CHACHA20-POLY1305 bits=256/256); Tue, 07 Apr 2020 07:33:08 -0700 (PDT) Date: Tue, 7 Apr 2020 20:03:04 +0530 From: Manivannan Sadhasivam To: Dan Carpenter Cc: linux-arm-msm@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: Re: [bug report] bus: mhi: core: Add support for data transfer Message-ID: <20200407143304.GH2442@Mani-XPS-13-9360> References: <20200407135559.GA109574@mwanda> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200407135559.GA109574@mwanda> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org Hi Dan, On Tue, Apr 07, 2020 at 04:55:59PM +0300, Dan Carpenter wrote: > Hello Manivannan Sadhasivam, > > The patch 189ff97cca53: "bus: mhi: core: Add support for data > transfer" from Feb 20, 2020, leads to the following static checker > warning: > > drivers/bus/mhi/core/main.c:1153 mhi_queue_buf() > error: double locked 'mhi_chan->lock' (orig line 1110) > > drivers/bus/mhi/core/main.c > 1142 } > 1143 > 1144 /* Toggle wake to exit out of M2 */ > 1145 mhi_cntrl->wake_toggle(mhi_cntrl); > 1146 > 1147 if (mhi_chan->dir == DMA_TO_DEVICE) > 1148 atomic_inc(&mhi_cntrl->pending_pkts); > 1149 > 1150 if (likely(MHI_DB_ACCESS_VALID(mhi_cntrl))) { > 1151 unsigned long flags; > 1152 > 1153 read_lock_irqsave(&mhi_chan->lock, flags); > ^^^^^^^^^^^^^^^ > The caller is already holding this lock. > Hmm. We have one internal user of this function and that's where the locking has gone wrong. Will fix it. Thanks for reporting! Regards, Mani > 1154 mhi_ring_chan_db(mhi_cntrl, mhi_chan); > 1155 read_unlock_irqrestore(&mhi_chan->lock, flags); > 1156 } > 1157 > 1158 read_unlock_irqrestore(&mhi_cntrl->pm_lock, flags); > 1159 > 1160 return 0; > 1161 } > 1162 EXPORT_SYMBOL_GPL(mhi_queue_buf); > > regards, > dan carpenter