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Message-ID: <ecdf9b68-ed90-9d8b-12e8-46e77c456890@linux.intel.com>
Date:   Fri, 16 Jun 2023 10:14:53 +0800
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Cc:     baolu.lu@linux.intel.com, iommu@lists.linux.dev,
        linux-kernel@vger.kernel.org,
        Venkata Rao Kakani <quic_vkakani@quicinc.com>,
        Vagdhan Kumar <quic_vagdhank@quicinc.com>
Subject: Re: [PATCH] iommu: export iommu_set_default_translated function
Content-Language: en-US
To:     Anvesh Jain P <quic_ajainp@quicinc.com>,
        Joerg Roedel <joro@8bytes.org>, Will Deacon <will@kernel.org>,
        Robin Murphy <robin.murphy@arm.com>
References: <20230615093308.24989-1-quic_ajainp@quicinc.com>
From:   Baolu Lu <baolu.lu@linux.intel.com>
In-Reply-To: <20230615093308.24989-1-quic_ajainp@quicinc.com>
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On 6/15/23 5:33 PM, Anvesh Jain P wrote:
> export iommu_set_default_translated function to be used by other modules.
> 
> Signed-off-by: Anvesh Jain P <quic_ajainp@quicinc.com>
> Signed-off-by: Venkata Rao Kakani <quic_vkakani@quicinc.com>
> Signed-off-by: Vagdhan Kumar <quic_vagdhank@quicinc.com>
> ---
>   drivers/iommu/iommu.c | 1 +
>   1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
> index f1dcfa3f1a1b..1b4a5db58d66 100644
> --- a/drivers/iommu/iommu.c
> +++ b/drivers/iommu/iommu.c
> @@ -2730,6 +2730,7 @@ void iommu_set_default_translated(bool cmd_line)
>   		iommu_cmd_line |= IOMMU_CMD_LINE_DMA_API;
>   	iommu_def_domain_type = IOMMU_DOMAIN_DMA;
>   }
> +EXPORT_SYMBOL_GPL(iommu_set_default_translated);

Exporting a symbol without using it is meaningless. It is better to
export and use it in a single series.

Additionally, there is a restriction on the use of this helper. Calling
it after the iommu probe has no effect.

>   
>   bool iommu_default_passthrough(void)
>   {
> 
> base-commit: b6dad5178ceaf23f369c3711062ce1f2afc33644

Best regards,
baolu