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Message-ID: <d838c7f8-2d31-2327-9b4d-c05b06a516bb@linux.intel.com>
Date:   Sat, 16 Apr 2022 08:04:42 +0800
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Cc:     baolu.lu@linux.intel.com, iommu@lists.linux-foundation.org,
        sven@svenpeter.dev, robdclark@gmail.com, m.szyprowski@samsung.com,
        yong.wu@mediatek.com, mjrosato@linux.ibm.com,
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        jean-philippe@linaro.org, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 02/13] iommu: Move bus setup to IOMMU device registration
Content-Language: en-US
To:     Robin Murphy <robin.murphy@arm.com>, joro@8bytes.org,
        will@kernel.org
References: <cover.1649935679.git.robin.murphy@arm.com>
 <e607a32be8e84c56d65160902f4bd3fb434ee9d3.1649935679.git.robin.murphy@arm.com>
From:   Lu Baolu <baolu.lu@linux.intel.com>
In-Reply-To: <e607a32be8e84c56d65160902f4bd3fb434ee9d3.1649935679.git.robin.murphy@arm.com>
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On 2022/4/14 20:42, Robin Murphy wrote:
> @@ -1883,27 +1900,12 @@ static int iommu_bus_init(struct bus_type *bus)
>    */
>   int bus_set_iommu(struct bus_type *bus, const struct iommu_ops *ops)
>   {
> -	int err;
> -
> -	if (ops == NULL) {
> -		bus->iommu_ops = NULL;
> -		return 0;
> -	}
> -
> -	if (bus->iommu_ops != NULL)
> +	if (bus->iommu_ops && ops && bus->iommu_ops != ops)
>   		return -EBUSY;
>   
>   	bus->iommu_ops = ops;

Do we still need to keep above lines in bus_set_iommu()?

Best regards,
baolu