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Subject: Re: [Resend RFC PATCH V4 13/13] x86/HV: Not set memory
 decrypted/encrypted during kexec alloc/free page in IVM
To:     Dave Hansen <dave.hansen@intel.com>, kys@microsoft.com,
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References: <20210707154629.3977369-1-ltykernel@gmail.com>
 <20210707154629.3977369-14-ltykernel@gmail.com>
 <3b5a1bd0-369a-2723-97c1-4ab4edb14eda@intel.com>
From:   Tianyu Lan <ltykernel@gmail.com>
Message-ID: <e4508d82-826e-86be-96cf-feecc1b4a260@gmail.com>
Date:   Thu, 8 Jul 2021 21:54:15 +0800
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Hi Dave:
      Thanks for your review.

On 7/8/2021 12:14 AM, Dave Hansen wrote:
> On 7/7/21 8:46 AM, Tianyu Lan wrote:
>> @@ -598,7 +599,7 @@ void arch_kexec_unprotect_crashkres(void)
>>    */
>>   int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages, gfp_t gfp)
>>   {
>> -	if (sev_active())
>> +	if (sev_active() || hv_is_isolation_supported())
>>   		return 0;
>>   
>>   	/*
>> @@ -611,7 +612,7 @@ int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages, gfp_t gfp)
>>   
>>   void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages)
>>   {
>> -	if (sev_active())
>> +	if (sev_active() || hv_is_isolation_supported())
>>   		return;
> 
> You might want to take a look through the "protected guest" patches.  I
> think this series is touching a few of the same locations that TDX and
> recent SEV work touch.
> 
> https://lore.kernel.org/lkml/20210618225755.662725-5-sathyanarayanan.kuppuswamy@linux.intel.com/

Thanks for reminder. You are right. There will be a generic API to check 
"proteced guest" type.