Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Subject: Re: [RFC PATCH V3 03/11] x86/Hyper-V: Add new hvcall guest address
 host visibility support
To:     Borislav Petkov <bp@alien8.de>
Cc:     kys@microsoft.com, haiyangz@microsoft.com, sthemmin@microsoft.com,
        wei.liu@kernel.org, decui@microsoft.com, tglx@linutronix.de,
        mingo@redhat.com, x86@kernel.org, hpa@zytor.com, arnd@arndb.de,
        dave.hansen@linux.intel.com, luto@kernel.org, peterz@infradead.org,
        akpm@linux-foundation.org, kirill.shutemov@linux.intel.com,
        rppt@kernel.org, hannes@cmpxchg.org, cai@lca.pw,
        krish.sadhukhan@oracle.com, saravanand@fb.com,
        Tianyu.Lan@microsoft.com, konrad.wilk@oracle.com, hch@lst.de,
        m.szyprowski@samsung.com, robin.murphy@arm.com,
        boris.ostrovsky@oracle.com, jgross@suse.com,
        sstabellini@kernel.org, joro@8bytes.org, will@kernel.org,
        xen-devel@lists.xenproject.org, davem@davemloft.net,
        kuba@kernel.org, jejb@linux.ibm.com, martin.petersen@oracle.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, thomas.lendacky@amd.com,
        brijesh.singh@amd.com, sunilmut@microsoft.com
References: <20210530150628.2063957-1-ltykernel@gmail.com>
 <20210530150628.2063957-4-ltykernel@gmail.com> <YLPYqxF7urDIAd9z@zn.tnic>
From:   Tianyu Lan <ltykernel@gmail.com>
Message-ID: <3716c9e0-2508-3553-5a70-e4b3f5f4c82e@gmail.com>
Date:   Mon, 31 May 2021 12:08:21 +0800
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101
 Thunderbird/78.10.2
MIME-Version: 1.0
In-Reply-To: <YLPYqxF7urDIAd9z@zn.tnic>
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Precedence: bulk

Hi Borislav:
	Thanks for your review.

On 5/31/2021 2:25 AM, Borislav Petkov wrote:
> On Sun, May 30, 2021 at 11:06:20AM -0400, Tianyu Lan wrote:
>> diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c
>> index 156cd235659f..a82975600107 100644
>> --- a/arch/x86/mm/pat/set_memory.c
>> +++ b/arch/x86/mm/pat/set_memory.c
>> @@ -29,6 +29,8 @@
>>   #include <asm/proto.h>
>>   #include <asm/memtype.h>
>>   #include <asm/set_memory.h>
>> +#include <asm/hyperv-tlfs.h>
>> +#include <asm/mshyperv.h>
>>   
>>   #include "../mm_internal.h"
>>   
>> @@ -1986,8 +1988,14 @@ static int __set_memory_enc_dec(unsigned long addr, int numpages, bool enc)
>>   	int ret;
>>   
>>   	/* Nothing to do if memory encryption is not active */
>> -	if (!mem_encrypt_active())
>> +	if (hv_is_isolation_supported()) {
>> +		return hv_set_mem_host_visibility((void *)addr,
>> +				numpages * HV_HYP_PAGE_SIZE,
>> +				enc ? VMBUS_PAGE_NOT_VISIBLE
>> +				: VMBUS_PAGE_VISIBLE_READ_WRITE);
> 
> Put all this gunk in a hv-specific function somewhere in hv-land which
> you only call from here. This way you probably won't even need to export
> hv_set_mem_host_visibility() and so on...
> 

Good idea. Will update. Thanks.