From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B9D00374DF; Thu, 9 Nov 2023 16:33:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="J3fFGh4K" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BB0E5C433CA; Thu, 9 Nov 2023 16:33:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1699547586; bh=iwH27tYu+P7Y1x7hZ5JuE532p4duwWE/n3Uu9Or2XNQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=J3fFGh4KIpq1TnzrNOmXXWidRYaHjfyeFKnciwAQyU/CejNlDAL+gnmPwCaBsgv9a /oXcreb34SttsF9ceHXowP42SupsqNQb0z1zgB+4cFjD6sBrlNgpyRMYuqJf5nOs7k yTKs5eE5dts7e4JZzFVowCe5qrekhcF9qhfNzeWLyWKAfwff3WMkXI4Rq/sdx69iu4 CsFdvxbDFGitd49vizBmG4+b3Z4GfjJUXek9AnjW0y3GXhgUR0h0lkG2+gCIUsm4ga Qeed+hpUZdLN9oKhmAy5EVR7t2ey9MJ5PR70/zeAQS6sRM+vMSa/cVHkh0buHket+R c7sdtjJCBarpQ== Date: Thu, 9 Nov 2023 22:02:53 +0530 From: Manivannan Sadhasivam To: Qiang Yu Cc: quic_jhugo@quicinc.com, mhi@lists.linux.dev, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, quic_cang@quicinc.com, quic_mrana@quicinc.com Subject: Re: [PATCH v3 3/4] bus: mhi: host: Avoid processing buffer and event of a disable channel Message-ID: <20231109163253.GL3752@thinkpad> References: <1699341365-47737-1-git-send-email-quic_qianyu@quicinc.com> <1699341365-47737-4-git-send-email-quic_qianyu@quicinc.com> Precedence: bulk X-Mailing-List: linux-arm-msm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1699341365-47737-4-git-send-email-quic_qianyu@quicinc.com> On Tue, Nov 07, 2023 at 03:16:04PM +0800, Qiang Yu wrote: > Ckeck mhi channel state after getting chan->lock to ensure that we only > queue buffer to an enabled channel and process event of an enabled channel. > This commit message doesn't give proper explanation on how the channel can go to disabled state in between parse_xfer_event() and mhi_gen_tre(). - Mani > Signed-off-by: Qiang Yu > --- > drivers/bus/mhi/host/main.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/bus/mhi/host/main.c b/drivers/bus/mhi/host/main.c > index a236dc2..b137d54 100644 > --- a/drivers/bus/mhi/host/main.c > +++ b/drivers/bus/mhi/host/main.c > @@ -672,6 +672,8 @@ static int parse_xfer_event(struct mhi_controller *mhi_cntrl, > } > > read_lock_bh(&mhi_chan->lock); > + if (mhi_chan->ch_state != MHI_CH_STATE_ENABLED) > + goto end_process_tx_event; > } > break; > } /* CC_EOT */ > @@ -1211,6 +1213,8 @@ int mhi_gen_tre(struct mhi_controller *mhi_cntrl, struct mhi_chan *mhi_chan, > > /* Protect accesses for reading and incrementing WP */ > write_lock_bh(&mhi_chan->lock); > + if (mhi_chan->ch_state != MHI_CH_STATE_ENABLED) > + return -EINVAL; > > buf_ring = &mhi_chan->buf_ring; > tre_ring = &mhi_chan->tre_ring; > -- > 2.7.4 > > -- மணிவண்ணன் சதாசிவம்