Message-ID: <bde64a70-7d9c-9e85-cd02-0301d4a0838e@linux.alibaba.com>
Date:   Sun, 29 Jan 2023 09:54:30 +0800
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Subject: Re: [PATCH 2/4] swiotlb: Add a new cc-swiotlb implementation for
 Confidential VMs
To:     Randy Dunlap <rdunlap@infradead.org>, linux-kernel@vger.kernel.org,
        iommu@lists.linux-foundation.org, konrad.wilk@oracle.com,
        linux-coco@lists.linux.dev
Cc:     robin.murphy@arm.com
References: <20230128083254.86012-1-GuoRui.Yu@linux.alibaba.com>
 <20230128083254.86012-3-GuoRui.Yu@linux.alibaba.com>
 <c966018b-95f0-7b92-0a5a-9023236b0dfb@infradead.org>
From:   Guorui Yu <GuoRui.Yu@linux.alibaba.com>
In-Reply-To: <c966018b-95f0-7b92-0a5a-9023236b0dfb@infradead.org>
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Hi Randy,

在 2023/1/29 00:41, Randy Dunlap 写道:
> Hi--
> 
> On 1/28/23 00:32, GuoRui.Yu wrote:
>> diff --git a/kernel/dma/Kconfig b/kernel/dma/Kconfig
>> index 56866aaa2ae1..7e6b20d2091f 100644
>> --- a/kernel/dma/Kconfig
>> +++ b/kernel/dma/Kconfig
>> @@ -78,8 +78,18 @@ config ARCH_HAS_FORCE_DMA_UNENCRYPTED
>>   
>>   config SWIOTLB
>>   	bool
>> +	depends on !CC_SWIOTLB
>>   	select NEED_DMA_MAP_STATE
>>   
>> +config CC_SWIOTLB
>> +	bool "Enable cc-swiotlb for Confidential VMs"
>> +	default n
>> +	select NEED_DMA_MAP_STATE
>> +	help
>> +	  This enables a cc-swiotlb implementation for Confidential VMs,
>> +	  which allows allocating the SWIOTLB buffer allocation on runtime.
> 
> Two "allocat..." words seems to be redundant. Probably the second one
> can be dropped.
> Also, instead of "on runtime", how about "at runtime"?

Thanks for your kindly advice, and I will fix it in the next version.

> 
>> +	  If unsure, say "n".
> 
> Thanks.

Sincerely,
Guorui