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Subject: Re: [PATCH] iommu: Add device name to iommu map/unmap trace events
To:     Joerg Roedel <joro@8bytes.org>,
        Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
References: <20210209123620.19993-1-saiprakash.ranjan@codeaurora.org>
 <20210212105039.GG7302@8bytes.org>
CC:     Will Deacon <will@kernel.org>, <linux-kernel@vger.kernel.org>,
        <iommu@lists.linux-foundation.org>,
        <linux-arm-msm@vger.kernel.org>,
        "Robin Murphy" <robin.murphy@arm.com>,
        <linux-arm-kernel@lists.infradead.org>, <linuxarm@huawei.com>
From:   "chenxiang (M)" <chenxiang66@hisilicon.com>
Message-ID: <626fbcb8-b84f-1522-4ec3-9c7c1f5f7a93@hisilicon.com>
Date:   Tue, 6 Apr 2021 14:56:53 +0800
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Hi,


在 2021/2/12 18:50, Joerg Roedel 写道:
> On Tue, Feb 09, 2021 at 06:06:20PM +0530, Sai Prakash Ranjan wrote:
>> diff --git a/include/linux/iommu.h b/include/linux/iommu.h
>> index 5e7fe519430a..6064187d9bb6 100644
>> --- a/include/linux/iommu.h
>> +++ b/include/linux/iommu.h
>> @@ -87,6 +87,7 @@ struct iommu_domain {
>>   	void *handler_token;
>>   	struct iommu_domain_geometry geometry;
>>   	void *iova_cookie;
>> +	char dev_name[32];
>>   };
> No, definitly not. A domain is a device DMA address space which can be
> used by more than one device. Just look at IOMMU groups with more than
> one member device, in this case just one device name would be very
> misleading.

Is it possible to use group id to identify different domains?


>
> Regards,
>
> 	Joerg
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> iommu@lists.linux-foundation.org
> https://lists.linuxfoundation.org/mailman/listinfo/iommu
>
> .
>