netdev - Re: [PATCH V3 10/13] x86/Swiotlb: Add Swiotlb bounce buffer remap function for HV IVM

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <1c5ae861-2c35-2ef5-e764-db45bbcb88a9@gmail.com>
Date:   Thu, 19 Aug 2021 17:59:02 +0800
From:   Tianyu Lan <ltykernel@...il.com>
To:     Christoph Hellwig <hch@....de>
Cc:     kys@...rosoft.com, haiyangz@...rosoft.com, sthemmin@...rosoft.com,
        wei.liu@...nel.org, decui@...rosoft.com, tglx@...utronix.de,
        mingo@...hat.com, bp@...en8.de, x86@...nel.org, hpa@...or.com,
        dave.hansen@...ux.intel.com, luto@...nel.org, peterz@...radead.org,
        konrad.wilk@...cle.com, boris.ostrovsky@...cle.com,
        jgross@...e.com, sstabellini@...nel.org, joro@...tes.org,
        will@...nel.org, davem@...emloft.net, kuba@...nel.org,
        jejb@...ux.ibm.com, martin.petersen@...cle.com, arnd@...db.de,
        m.szyprowski@...sung.com, robin.murphy@....com,
        thomas.lendacky@....com, brijesh.singh@....com, ardb@...nel.org,
        Tianyu.Lan@...rosoft.com, pgonda@...gle.com,
        martin.b.radev@...il.com, akpm@...ux-foundation.org,
        kirill.shutemov@...ux.intel.com, rppt@...nel.org,
        sfr@...b.auug.org.au, saravanand@...com,
        krish.sadhukhan@...cle.com, aneesh.kumar@...ux.ibm.com,
        xen-devel@...ts.xenproject.org, rientjes@...gle.com,
        hannes@...xchg.org, tj@...nel.org, michael.h.kelley@...rosoft.com,
        iommu@...ts.linux-foundation.org, linux-arch@...r.kernel.org,
        linux-hyperv@...r.kernel.org, linux-kernel@...r.kernel.org,
        linux-scsi@...r.kernel.org, netdev@...r.kernel.org,
        vkuznets@...hat.com, parri.andrea@...il.com, dave.hansen@...el.com
Subject: Re: [PATCH V3 10/13] x86/Swiotlb: Add Swiotlb bounce buffer remap
 function for HV IVM



On 8/19/2021 4:49 PM, Christoph Hellwig wrote:
> On Mon, Aug 16, 2021 at 10:50:26PM +0800, Tianyu Lan wrote:
>> Hi Christoph:
>>        Sorry to bother you.Please double check with these two patches
>> " [PATCH V3 10/13] x86/Swiotlb: Add Swiotlb bounce buffer remap function
>> for HV IVM" and "[PATCH V3 09/13] DMA: Add dma_map_decrypted/dma_
>> unmap_encrypted() function".
> 
> Do you have a git tree somewhere to look at the whole tree?

Yes, here is my github link for these two patches.

https://github.com/lantianyu/linux/commit/462f7e4e44644fe7e182f7a5fb043a75acb90ee5

https://github.com/lantianyu/linux/commit/c8de236bf4366d39e8b98e5a091c39df29b03e0b

> 
>>        The swiotlb bounce buffer in the isolation VM are allocated in the
>> low end memory and these memory has struct page backing. All dma address
>> returned by swiotlb/DMA API are low end memory and this is as same as what
>> happen in the traditional VM.
> 
> Indeed.
> 
>>        The API dma_map_decrypted() introduced in the patch 9 is to map the
>> bounce buffer in the extra space and these memory in the low end space are
>> used as DMA memory in the driver. Do you prefer these APIs
>> still in the set_memory.c? I move the API to dma/mapping.c due to the
>> suggested name arch_dma_map_decrypted() in the previous mail
>> (https://lore.kernel.org/netdev/20210720135437.GA13554@lst.de/).
> 
> Well, what would help is a clear description of the semantics.
> 

Yes, I will improve description.