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=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 D72D9C433E0 for ; Fri, 26 Feb 2021 14:25:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8F54C64EDB for ; Fri, 26 Feb 2021 14:25:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229752AbhBZOZC (ORCPT ); Fri, 26 Feb 2021 09:25:02 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50578 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230153AbhBZOYr (ORCPT ); Fri, 26 Feb 2021 09:24:47 -0500 Received: from mail-pf1-x434.google.com (mail-pf1-x434.google.com [IPv6:2607:f8b0:4864:20::434]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 62C25C06174A for ; Fri, 26 Feb 2021 06:24:06 -0800 (PST) Received: by mail-pf1-x434.google.com with SMTP id q20so6342739pfu.8 for ; Fri, 26 Feb 2021 06:24:06 -0800 (PST) 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; bh=DAaGVb7r/TvUsy8AGyqpjJMg3/kOQ92bLhl4QPZ8jWQ=; b=ThkH0JGDreGtf7pDodavSruoyKWVlP6UhhqIi8iEzROkRM4R1TxDRFn7N6oIPdSOMH cArjbf+V7/Aku9RZ1LwYtBXKEkSdAW5YGyf20rTPm8P24SsV0HMgmolhHVfSNZnIiw7c U2hdFI8462mUBWSvLStzw7wlUyKascYNVarK9VtWQMJ1csUQ9oDBVYCBu5tbXLx6gN99 bLXUszavhYF4cHmsXph/Ctp2hcSuEg0bk+Sbx5XEmW1V0MgUZ0dscPqfEiDdSiRwAq3b 96z5Y3xlLudUdPwmvQjETW/eBZJNYuluwknAT7SR1yOlRYm4jS2tXSkJBzzwGG80sjJW 8l3A== 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; bh=DAaGVb7r/TvUsy8AGyqpjJMg3/kOQ92bLhl4QPZ8jWQ=; b=MAn4uO4pAwnm2CsFXRWoidVjeM2UWiOop2XRyEDW3lpmeLRwYTReJ26+PAkY/yvigS G0V+WLL2Vtn+y+vBopQSLJ47mej9kq3z+PN2BYNIW7KATve9ZgehP6QGwzKkjoZDFu6Q tjTrMMN88UqCsb2Q8jrvZ7m+aNM0lXZb7MmVs263BpaBtqVEv5UpnbtbtuYok+WdA+Dr RVxgfvT5qcT4tNk8FhRdfghpkYBfC+sQdYujc1xeznTpDwZT8RPat1NOz1sI20yWtI/r 9zIHcpdFcyIzC/IRUrPLpL3gT8tZCkL+Nrkx1Y+dQW3SFh9bxL49sGq5HhERtoMy9qAg vDfQ== X-Gm-Message-State: AOAM5309PepQkkyE/epRB1W/gWNjIZV85oHoh9jhHFX4D/9RfB/Qrk+r 0kQ1gzxXBi9xDatYP6UqcI5d3wMsNf3S X-Google-Smtp-Source: ABdhPJxrQR7OSm5JKfZUozWBCsMpp2KpH5Gu5fLdAUV4qHKqKFXV4f7Va/ZfzQNmj0/CNr2VR+24UQ== X-Received: by 2002:a05:6a00:1681:b029:1ec:c756:7ec3 with SMTP id k1-20020a056a001681b02901ecc7567ec3mr3497302pfc.13.1614349445812; Fri, 26 Feb 2021 06:24:05 -0800 (PST) Received: from thinkpad ([103.66.79.124]) by smtp.gmail.com with ESMTPSA id u3sm10703006pfm.144.2021.02.26.06.24.03 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 26 Feb 2021 06:24:05 -0800 (PST) Date: Fri, 26 Feb 2021 19:54:01 +0530 From: Manivannan Sadhasivam To: Loic Poulain Cc: hemantk@codeaurora.org, jhugo@codeaurora.org, bbhatt@codeaurora.org, linux-arm-msm@vger.kernel.org Subject: Re: [PATCH v2] mhi: Fix invalid error returning in mhi_queue Message-ID: <20210226142401.GA70936@thinkpad> References: <1614336782-5809-1-git-send-email-loic.poulain@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1614336782-5809-1-git-send-email-loic.poulain@linaro.org> Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On Fri, Feb 26, 2021 at 11:53:02AM +0100, Loic Poulain wrote: > mhi_queue returns an error when the doorbell is not accessible in > the current state. This can happen when the device is in non M0 > state, like M3, and needs to be waken-up prior ringing the DB. This > case is managed earlier by triggering an asynchronous M3 exit via > controller resume/suspend callbacks, that in turn will cause M0 > transition and DB update. > > So, since it's not an error but just delaying of doorbell update, there > is no reason to return an error. > > This also fixes a use after free error for skb case, indeed a caller > queuing skb will try to free the skb if the queueing fails, but in > that case queueing has been done. > > Fixes: a8f75cb348fd ("mhi: core: Factorize mhi queuing") > Signed-off-by: Loic Poulain > Reviewed-by: Jeffrey Hugo > Reviewed-by: Bhaumik Bhatt Reviewed-by: Manivannan Sadhasivam Thanks, Mani > --- > v2: - Fix/reword commit message > - Add Fixes tag > > drivers/bus/mhi/core/main.c | 8 ++------ > 1 file changed, 2 insertions(+), 6 deletions(-) > > diff --git a/drivers/bus/mhi/core/main.c b/drivers/bus/mhi/core/main.c > index 7fc2482..c780234 100644 > --- a/drivers/bus/mhi/core/main.c > +++ b/drivers/bus/mhi/core/main.c > @@ -1031,12 +1031,8 @@ static int mhi_queue(struct mhi_device *mhi_dev, struct mhi_buf_info *buf_info, > if (mhi_chan->dir == DMA_TO_DEVICE) > atomic_inc(&mhi_cntrl->pending_pkts); > > - if (unlikely(!MHI_DB_ACCESS_VALID(mhi_cntrl))) { > - ret = -EIO; > - goto exit_unlock; > - } > - > - mhi_ring_chan_db(mhi_cntrl, mhi_chan); > + if (likely(MHI_DB_ACCESS_VALID(mhi_cntrl))) > + mhi_ring_chan_db(mhi_cntrl, mhi_chan); > > exit_unlock: > read_unlock_irqrestore(&mhi_cntrl->pm_lock, flags); > -- > 2.7.4 >