Message-ID: <7ec6bd88-7f18-7eca-fa92-cfea9a25a395@arm.com>
Date:   Thu, 26 Jan 2023 18:02:19 +0000
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Subject: Re: [PATCH] Coresight: tpda/tpdm: remove incorrect __exit annotation
To:     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:     Arnd Bergmann <arnd@arndb.de>, 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>
From:   Suzuki K Poulose <suzuki.poulose@arm.com>
In-Reply-To: <20230126163530.3495413-1-arnd@kernel.org>
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Precedence: bulk

Hi Arnd,

On 26/01/2023 16:35, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@arndb.de>
> 
> 'remove' callbacks get called whenever a device is unbound from
> the driver, which can get triggered from user space.
> 
> Putting it into the __exit section means that the function gets
> dropped in for built-in drivers, as pointed out by this build
> warning:

> 
> `tpda_remove' referenced in section `.data' of drivers/hwtracing/coresight/coresight-tpda.o: defined in discarded section `.exit.text' of drivers/hwtracing/coresight/coresight-tpda.o
> `tpdm_remove' referenced in section `.data' of drivers/hwtracing/coresight/coresight-tpdm.o: defined in discarded section `.exit.text' of drivers/hwtracing/coresight/coresight-tpdm.o
> 

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) ?

Suzuki


> Fixes: 5b7916625c01 ("Coresight: Add TPDA link driver")
> Fixes: b3c71626a933 ("Coresight: Add coresight TPDM source driver")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>


> ---
>   drivers/hwtracing/coresight/coresight-tpda.c | 2 +-
>   drivers/hwtracing/coresight/coresight-tpdm.c | 2 +-
>   2 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/hwtracing/coresight/coresight-tpda.c b/drivers/hwtracing/coresight/coresight-tpda.c
> index 19c25c9f6157..382d648529e7 100644
> --- a/drivers/hwtracing/coresight/coresight-tpda.c
> +++ b/drivers/hwtracing/coresight/coresight-tpda.c
> @@ -174,7 +174,7 @@ static int tpda_probe(struct amba_device *adev, const struct amba_id *id)
>   	return 0;
>   }
>   
> -static void __exit tpda_remove(struct amba_device *adev)
> +static void tpda_remove(struct amba_device *adev)
>   {
>   	struct tpda_drvdata *drvdata = dev_get_drvdata(&adev->dev);
>   
> diff --git a/drivers/hwtracing/coresight/coresight-tpdm.c b/drivers/hwtracing/coresight/coresight-tpdm.c
> index 349a82bb3270..9479a5e8c672 100644
> --- a/drivers/hwtracing/coresight/coresight-tpdm.c
> +++ b/drivers/hwtracing/coresight/coresight-tpdm.c
> @@ -223,7 +223,7 @@ static int tpdm_probe(struct amba_device *adev, const struct amba_id *id)
>   	return 0;
>   }
>   
> -static void __exit tpdm_remove(struct amba_device *adev)
> +static void tpdm_remove(struct amba_device *adev)
>   {
>   	struct tpdm_drvdata *drvdata = dev_get_drvdata(&adev->dev);
>