Message-ID: <4006e942-b6bf-ac21-c56b-4719e514dbd2@gmail.com>
Date:   Fri, 3 Dec 2021 19:25:52 +0800
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Subject: Re: [PATCH V3 3/5] hyperv/IOMMU: Enable swiotlb bounce buffer for
 Isolation VM
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To:     Wei Liu <wei.liu@kernel.org>
Cc:     kys@microsoft.com, haiyangz@microsoft.com, sthemmin@microsoft.com,
        decui@microsoft.com, tglx@linutronix.de, mingo@redhat.com,
        bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org,
        hpa@zytor.com, jgross@suse.com, sstabellini@kernel.org,
        boris.ostrovsky@oracle.com, joro@8bytes.org, will@kernel.org,
        davem@davemloft.net, kuba@kernel.org, jejb@linux.ibm.com,
        martin.petersen@oracle.com, arnd@arndb.de, hch@infradead.org,
        m.szyprowski@samsung.com, robin.murphy@arm.com,
        Tianyu.Lan@microsoft.com, thomas.lendacky@amd.com,
        xen-devel@lists.xenproject.org, michael.h.kelley@microsoft.com,
        iommu@lists.linux-foundation.org, linux-arch@vger.kernel.org,
        linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-scsi@vger.kernel.org, netdev@vger.kernel.org,
        vkuznets@redhat.com, brijesh.singh@amd.com, konrad.wilk@oracle.com,
        hch@lst.de, parri.andrea@gmail.com, dave.hansen@intel.com
References: <20211201160257.1003912-1-ltykernel@gmail.com>
 <20211201160257.1003912-4-ltykernel@gmail.com>
 <20211202144336.z2sfs6kw5kdsfqgv@liuwe-devbox-debian-v2>
From:   Tianyu Lan <ltykernel@gmail.com>
In-Reply-To: <20211202144336.z2sfs6kw5kdsfqgv@liuwe-devbox-debian-v2>
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On 12/2/2021 10:43 PM, Wei Liu wrote:
> On Wed, Dec 01, 2021 at 11:02:54AM -0500, Tianyu Lan wrote:
> [...]
>> diff --git a/arch/x86/xen/pci-swiotlb-xen.c b/arch/x86/xen/pci-swiotlb-xen.c
>> index 46df59aeaa06..30fd0600b008 100644
>> --- a/arch/x86/xen/pci-swiotlb-xen.c
>> +++ b/arch/x86/xen/pci-swiotlb-xen.c
>> @@ -4,6 +4,7 @@
>>   
>>   #include <linux/dma-map-ops.h>
>>   #include <linux/pci.h>
>> +#include <linux/hyperv.h>
>>   #include <xen/swiotlb-xen.h>
>>   
>>   #include <asm/xen/hypervisor.h>
>> @@ -91,6 +92,6 @@ int pci_xen_swiotlb_init_late(void)
>>   EXPORT_SYMBOL_GPL(pci_xen_swiotlb_init_late);
>>   
>>   IOMMU_INIT_FINISH(pci_xen_swiotlb_detect,
>> -		  NULL,
>> +		  hyperv_swiotlb_detect,
> 
> It is not immediately obvious why this is needed just by reading the
> code. Please consider copying some of the text in the commit message to
> a comment here.
> 

Thanks for suggestion. Will update.