Message-ID: <e6c3fa24-963b-57c0-1a9a-fd056a9ac591@arm.com>
Date:   Fri, 27 Jan 2023 16:46:21 +0000
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Subject: Re: [PATCH] Coresight: tpda/tpdm: remove incorrect __exit annotation
To:     Arnd Bergmann <arnd@arndb.de>, Arnd Bergmann <arnd@kernel.org>,
        Mathieu Poirier <mathieu.poirier@linaro.org>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Tao Zhang <quic_taozha@quicinc.com>,
        Mao Jinlong <quic_jinlmao@quicinc.com>
Cc:     Mike Leach <mike.leach@linaro.org>, Leo Yan <leo.yan@linaro.org>,
        coresight@lists.linaro.org, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org
References: <20230126163530.3495413-1-arnd@kernel.org>
 <7ec6bd88-7f18-7eca-fa92-cfea9a25a395@arm.com>
 <cd4f23d7-cdd7-49e1-8eff-9ec04dcb36c8@app.fastmail.com>
From:   Suzuki K Poulose <suzuki.poulose@arm.com>
In-Reply-To: <cd4f23d7-cdd7-49e1-8eff-9ec04dcb36c8@app.fastmail.com>
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On 26/01/2023 20:37, Arnd Bergmann wrote:
> On Thu, Jan 26, 2023, at 19:02, Suzuki K Poulose wrote:
>> On 26/01/2023 16:35, Arnd Bergmann wrote:
>>> From: Arnd Bergmann <arnd@arndb.de>
>> Thanks for the fix, I will queue this. Btw, I did try to
>> reproduce it locally, but couldn't trigger the warnings,
>> even with
>>
>> CONFIG_WERROR=y
>>
>> and all CORESIGHT configs builtin. I see other drivers doing the
>> same outside coresight too. Just curious to know why is this
>> any different. Is it specific to "bus" driver (e.g. AMBA) ?
> 
> The warning comes from postprocessing the object file, it's got
> nothing to do with the bus type, only with a symbol in .data
> referencing a symbol in .init.text. Maybe there are some
> config options that keep the section from getting discarded?
> Or possibly you only built the files in this directory, but did
> not get to the final link?

I did a full kernel build. Also, I see a similar issue with the 
coresight-etm4x (by code inspection) driver. Did you not hit that ?

May be there is a config option that is masking it on my end. But
the case of etm4x driver is puzzling.

$ git grep etm4_remove_amba 
drivers/hwtracing/coresight/coresight-etm4x-core.c
drivers/hwtracing/coresight/coresight-etm4x-core.c:static void __exit 
etm4_remove_amba(struct amba_device *adev)
drivers/hwtracing/coresight/coresight-etm4x-core.c:     .remove 
= etm4_remove_amba,

Suzuki


> 


>        Arnd