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Subject: Re: [PATCH Part1 RFC v4 02/36] x86/sev: Save the negotiated GHCB
 version
To:     Borislav Petkov <bp@alien8.de>
References: <20210707181506.30489-1-brijesh.singh@amd.com>
 <20210707181506.30489-3-brijesh.singh@amd.com> <YRJEE6C/NC3Epa8G@zn.tnic>
From:   Brijesh Singh <brijesh.singh@amd.com>
Message-ID: <3b156915-3761-67f9-4256-76196bb87a7a@amd.com>
Date:   Tue, 10 Aug 2021 08:15:48 -0500
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On 8/10/21 4:17 AM, Borislav Petkov wrote:
> On Wed, Jul 07, 2021 at 01:14:32PM -0500, Brijesh Singh wrote:
>> diff --git a/arch/x86/kernel/sev-shared.c b/arch/x86/kernel/sev-shared.c
>> index 114f62fe2529..19c2306ac02d 100644
>> --- a/arch/x86/kernel/sev-shared.c
>> +++ b/arch/x86/kernel/sev-shared.c
>> @@ -14,6 +14,15 @@
>>   #define has_cpuflag(f)	boot_cpu_has(f)
>>   #endif
>>   
>> +/*
>> + * Since feature negotiation related variables are set early in the boot
>> + * process they must reside in the .data section so as not to be zeroed
>> + * out when the .bss section is later cleared.
>> + *
>> + * GHCB protocol version negotiated with the hypervisor.
>> + */
>> +static u16 ghcb_version __section(".data..ro_after_init");
> 
> There's a define for that section specifier: __ro_after_init
> 

Noted.

thanks