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Date:   Mon, 26 Dec 2022 15:26:30 +0800
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Subject: Re: [RFC PATCH V2 10/18] drivers: hv: Decrypt percpu hvcall input arg
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To:     "Michael Kelley (LINUX)" <mikelley@microsoft.com>,
        "luto@kernel.org" <luto@kernel.org>,
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        Tianyu Lan <Tianyu.Lan@microsoft.com>,
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References: <20221119034633.1728632-1-ltykernel@gmail.com>
 <20221119034633.1728632-11-ltykernel@gmail.com>
 <BYAPR21MB168878729E4A76AFC9B3E053D7E09@BYAPR21MB1688.namprd21.prod.outlook.com>
From:   Tianyu Lan <ltykernel@gmail.com>
In-Reply-To: <BYAPR21MB168878729E4A76AFC9B3E053D7E09@BYAPR21MB1688.namprd21.prod.outlook.com>
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On 12/15/2022 2:16 AM, Michael Kelley (LINUX) wrote:
>> @@ -134,6 +136,16 @@ int hv_common_cpu_init(unsigned int cpu)
>>   	if (!(*inputarg))
>>   		return -ENOMEM;
>>
>> +	if (hv_isolation_type_en_snp()) {
>> +		ret = set_memory_decrypted((unsigned long)*inputarg, 1);
>> +		if (ret) {
>> +			kfree(*inputarg);
> After the kfree(), set *inputarg back to NULL.  There's other code that
> tests the value of *inputarg to know if the per-CPU hypercall page has
> been successfully allocated.
> 

Good point! Will add in the next version.