linux-kernel - Re: [PATCH v4 3/3] x86/kvm: Expose AMD Core Perf Extension flag to guests

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <1ab1c7a9-a55b-2903-50c7-444886ac1bfe@amd.com>
Date:   Mon, 5 Feb 2018 11:48:00 -0600
From:   "Natarajan, Janakarajan" <Janakarajan.Natarajan@....com>
To:     Radim Krcmar <rkrcmar@...hat.com>
Cc:     kvm@...r.kernel.org, x86@...nel.org, linux-kernel@...r.kernel.org,
        Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>,
        "H . Peter Anvin" <hpa@...or.com>,
        Paolo Bonzini <pbonzini@...hat.com>,
        Len Brown <len.brown@...el.com>, Kyle Huey <me@...ehuey.com>,
        Tom Lendacky <thomas.lendacky@....com>,
        Borislav Petkov <bp@...e.de>,
        Grzegorz Andrejczuk <grzegorz.andrejczuk@...el.com>,
        Kan Liang <Kan.liang@...el.com>
Subject: Re: [PATCH v4 3/3] x86/kvm: Expose AMD Core Perf Extension flag to
 guests

On 2/5/2018 7:43 AM, Radim Krcmar wrote:
> 2018-01-30 11:32-0600, Janakarajan Natarajan:
>> Expose the AMD Core Perf Extension flag to the guests.
>>
>> Signed-off-by: Janakarajan Natarajan <Janakarajan.Natarajan@....com>
>> ---
>> diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
>> @@ -365,7 +371,7 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
>>   		F(LAHF_LM) | F(CMP_LEGACY) | 0 /*SVM*/ | 0 /* ExtApicSpace */ |
>>   		F(CR8_LEGACY) | F(ABM) | F(SSE4A) | F(MISALIGNSSE) |
>>   		F(3DNOWPREFETCH) | F(OSVW) | 0 /* IBS */ | F(XOP) |
>> -		0 /* SKINIT, WDT, LWP */ | F(FMA4) | F(TBM);
>> +		0 /* SKINIT, WDT, LWP */ | F(FMA4) | F(TBM) | f_perfext;
> You can just say F(PERFCTR_CORE) here.  The conditional features are
> needed when there is a runtime config option for them.  We are
> automatically masking features that the host doesn't support,

Okay. I'll send a v5 with the changes.

Thanks.

>
> thanks.
>
>>   
>>   	/* cpuid 0xC0000001.edx */
>>   	const u32 kvm_cpuid_C000_0001_edx_x86_features =
>> -- 
>> 2.7.4
>>