Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.38 as permitted sender) client-ip=23.128.96.38;
Message-ID: <94770fc6-7d72-8283-5858-786685620d5c@linaro.org>
Date:   Tue, 12 Sep 2023 11:54:17 +0200
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101
 Thunderbird/102.15.0
Subject: Re: [PATCH v5 06/17] soc: qcom: Add Qualcomm APSS minidump kernel
 driver
Content-Language: en-US
To:     Mukesh Ojha <quic_mojha@quicinc.com>, corbet@lwn.net,
        agross@kernel.org, andersson@kernel.org, konrad.dybcio@linaro.org,
        robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org,
        conor+dt@kernel.org, keescook@chromium.org, tony.luck@intel.com,
        gpiccoli@igalia.com, mathieu.poirier@linaro.org,
        catalin.marinas@arm.com, will@kernel.org, linus.walleij@linaro.org,
        andy.shevchenko@gmail.com, vigneshr@ti.com, nm@ti.com,
        matthias.bgg@gmail.com, kgene@kernel.org, alim.akhtar@samsung.com,
        bmasney@redhat.com, quic_tsoni@quicinc.com
Cc:     linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-arm-msm@vger.kernel.org, linux-hardening@vger.kernel.org,
        linux-remoteproc@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, linux-gpio@vger.kernel.org,
        linux-mediatek@lists.infradead.org,
        linux-samsung-soc@vger.kernel.org, kernel@quicinc.com
References: <1694290578-17733-1-git-send-email-quic_mojha@quicinc.com>
 <1694290578-17733-7-git-send-email-quic_mojha@quicinc.com>
 <3bb1e84f-3b65-0596-1b6b-6decb0ff53cc@linaro.org>
 <0eeef9c4-14c0-8283-803b-4684854d4be6@quicinc.com>
From:   Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
In-Reply-To: <0eeef9c4-14c0-8283-803b-4684854d4be6@quicinc.com>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 7bit
Precedence: bulk

On 12/09/2023 11:26, Mukesh Ojha wrote:
>>
>>> +		return -EINVAL;
>>> +	}
>>> +
>>> +	mutex_init(&md->md_lock);
>>> +	ret = qcom_apss_md_table_init(md, &mdgtoc->subsystems[MINIDUMP_APSS_DESC]);
>>> +	if (ret) {
>>> +		dev_err(md->dev, "apss minidump initialization failed: %d\n", ret);
>>> +		return ret;
>>> +	}
>>> +
>>> +	/* First entry would be ELF header */
>>> +	ret = qcom_md_add_elfheader(md);
>>> +	if (ret) {
>>> +		dev_err(md->dev, "Failed to add elf header: %d\n", ret);
>>> +		memset(md->apss_data->md_ss_toc, 0, sizeof(struct minidump_subsystem));
>>
>> Why do you need it?
> 
> Earlier, i got comment about clearing the SS TOC(subsystem table of 
> content) which is shared with other SS and it will have stale values.

OK, but then the entire code is poorly readable. First, any cleanup of
qcom_apss_md_table_init() should be named similarly, e.g.
qcom_apss_md_table_clean() or qcom_apss_md_table_exit() or whatever
seems feasible.

Second, shouldn't writing to shared memory be the last step? Step which
cannot fail and there is no cleanup afterwards (like
platform_set_drvdata)? I don't enjoy looking at this interface...


Best regards,
Krzysztof