All the mail mirrored from lore.kernel.org
 help / color / mirror / Atom feed
From: "Kuppuswamy, Sathyanarayanan"  <sathyanarayanan.kuppuswamy@linux.intel.com>
To: Borislav Petkov <bp@alien8.de>
Cc: Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Andy Lutomirski <luto@kernel.org>, Peter H Anvin <hpa@zytor.com>,
	Dave Hansen <dave.hansen@intel.com>,
	Tony Luck <tony.luck@intel.com>,
	Dan Williams <dan.j.williams@intel.com>,
	Andi Kleen <ak@linux.intel.com>,
	Kirill Shutemov <kirill.shutemov@linux.intel.com>,
	Kuppuswamy Sathyanarayanan <knsathya@kernel.org>,
	Sean Christopherson <seanjc@google.com>,
	linux-kernel@vger.kernel.org, x86@kernel.org
Subject: Re: [PATCH v1 04/11] x86/x86: Add is_tdx_guest() interface
Date: Thu, 10 Jun 2021 14:01:41 -0700	[thread overview]
Message-ID: <3437ff11-4656-2c2a-ae58-04b77b6ff663@linux.intel.com> (raw)
In-Reply-To: <YMJvNGyIaBItV9c6@zn.tnic>



On 6/10/21 12:59 PM, Borislav Petkov wrote:
> On Tue, Jun 01, 2021 at 07:21:29PM -0700, Kuppuswamy Sathyanarayanan wrote:

>> +	if (memcmp("IntelTDX    ", signature, 12))
>> +		return false;
>> +
>> +	return true;
> 
> As before,
> 
>   return !memcmp(...
> 
> and then that function can return simply an int.

I will make the above change in next version.

> 
> 
>> +}
>> +
>> +bool is_tdx_guest(void)
> 
> If anything, this should be early_is_tdx_guest().

If this is the recommendation, I am fine with it. It is
only used by __in/__out macros in decompression code.

> 
>> +{
>> +	if (tdx_guest < 0)
>> +		tdx_guest = native_cpuid_has_tdx_guest();
>> +
>> +	return !!tdx_guest;
>> +}
>> +
> 
> Applying: x86/x86: Add is_tdx_guest() interface
> .git/rebase-apply/patch:58: new blank line at EOF.
> +
> warning: 1 line adds whitespace errors.

I will fix it in next version.

> 
> 
>> diff --git a/arch/x86/kernel/tdx.c b/arch/x86/kernel/tdx.c
>> index 5b14b72e41c5..5e70617e9877 100644
>> --- a/arch/x86/kernel/tdx.c
>> +++ b/arch/x86/kernel/tdx.c
>> @@ -19,6 +19,12 @@ static inline bool cpuid_has_tdx_guest(void)
>>   	return true;
>>   }
>>   
>> +bool is_tdx_guest(void)
>> +{
>> +	return static_cpu_has(X86_FEATURE_TDX_GUEST);
>> +}
>> +EXPORT_SYMBOL_GPL(is_tdx_guest);
> 
> I don't like this is_tdx_guest() thing in kernel proper - what's wrong
> with
> 
>    prot_guest_has(PR_GUEST_TDX)

Is it alright to use vendor name in prot_guest_has() flag? I thought
we want to keep them generic. If this is acceptable, we can replace
is_tdx_guest() with prot_guest_has() calls. Currently it is not used
in many places.

> 
> ?
> 
> Also, why is it exported, for kvm?

Yes. It is used in exported KVM functions.

> 
> Thx.
> 

-- 
Sathyanarayanan Kuppuswamy
Linux Kernel Developer

  reply	other threads:[~2021-06-10 21:02 UTC|newest]

Thread overview: 35+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-06-02  2:21 [PATCH v1 00/11] Add TDX Guest Support (Initial support) Kuppuswamy Sathyanarayanan
2021-06-02  2:21 ` [PATCH v1 01/11] x86/paravirt: Move halt paravirt calls under CONFIG_PARAVIRT Kuppuswamy Sathyanarayanan
2021-06-02  2:21 ` [PATCH v1 02/11] x86/tdx: Introduce INTEL_TDX_GUEST config option Kuppuswamy Sathyanarayanan
2021-06-02  2:21 ` [PATCH v1 03/11] x86/cpufeatures: Add TDX Guest CPU feature Kuppuswamy Sathyanarayanan
2021-06-07 14:32   ` Tom Lendacky
2021-06-07 16:59     ` Kuppuswamy, Sathyanarayanan
2021-06-10 12:28   ` Borislav Petkov
2021-06-10 14:28     ` Kuppuswamy, Sathyanarayanan
2021-06-10 14:29     ` Kirill A. Shutemov
2021-06-10 14:35       ` Borislav Petkov
2021-06-10 14:41         ` Kirill A. Shutemov
2021-06-10 15:56           ` Borislav Petkov
2021-06-12 21:02             ` [PATCH v2 03/12] " Kuppuswamy Sathyanarayanan
2021-06-16  9:52               ` Borislav Petkov
2021-06-16 16:57                 ` Kuppuswamy, Sathyanarayanan
2021-06-02  2:21 ` [PATCH v1 04/11] x86/x86: Add is_tdx_guest() interface Kuppuswamy Sathyanarayanan
2021-06-10 19:59   ` Borislav Petkov
2021-06-10 21:01     ` Kuppuswamy, Sathyanarayanan [this message]
2021-06-10 21:07       ` Borislav Petkov
2021-06-12 21:04         ` [PATCH v2 04/12] x86/x86: Add early_is_tdx_guest() interface Kuppuswamy Sathyanarayanan
2021-06-17 17:05           ` Borislav Petkov
2021-06-18 19:14             ` Kuppuswamy, Sathyanarayanan
2021-06-02  2:21 ` [PATCH v1 05/11] x86/tdx: Add __tdx_module_call() and __tdx_hypercall() helper functions Kuppuswamy Sathyanarayanan
2021-06-14  8:47   ` Borislav Petkov
2021-06-14 19:45     ` Kuppuswamy, Sathyanarayanan
2021-06-14 20:11       ` Borislav Petkov
2021-06-14 21:37         ` Kuppuswamy, Sathyanarayanan
2021-06-02  2:21 ` [PATCH v1 06/11] x86/tdx: Get TD execution environment information via TDINFO Kuppuswamy Sathyanarayanan
2021-06-02  2:21 ` [PATCH v1 07/11] x86/traps: Add #VE support for TDX guest Kuppuswamy Sathyanarayanan
2021-06-02  2:21 ` [PATCH v1 08/11] x86/tdx: Add HLT " Kuppuswamy Sathyanarayanan
2021-06-02  2:21 ` [PATCH v1 09/11] x86/tdx: Wire up KVM hypercalls Kuppuswamy Sathyanarayanan
2021-06-12 21:08   ` [PATCH v2 10/12] " Kuppuswamy Sathyanarayanan
2021-06-02  2:21 ` [PATCH v1 10/11] x86/tdx: Add MSR support for TDX guest Kuppuswamy Sathyanarayanan
2021-06-02  2:21 ` [PATCH v1 11/11] x86/tdx: Handle CPUID via #VE Kuppuswamy Sathyanarayanan
  -- strict thread matches above, loose matches on Subject: below --
2021-06-02  2:18 [PATCH v1 00/11] Add TDX Guest Support (Initial support) Kuppuswamy Sathyanarayanan
2021-06-02  2:18 ` [PATCH v1 04/11] x86/x86: Add is_tdx_guest() interface Kuppuswamy Sathyanarayanan

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=3437ff11-4656-2c2a-ae58-04b77b6ff663@linux.intel.com \
    --to=sathyanarayanan.kuppuswamy@linux.intel.com \
    --cc=ak@linux.intel.com \
    --cc=bp@alien8.de \
    --cc=dan.j.williams@intel.com \
    --cc=dave.hansen@intel.com \
    --cc=hpa@zytor.com \
    --cc=kirill.shutemov@linux.intel.com \
    --cc=knsathya@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=luto@kernel.org \
    --cc=mingo@redhat.com \
    --cc=peterz@infradead.org \
    --cc=seanjc@google.com \
    --cc=tglx@linutronix.de \
    --cc=tony.luck@intel.com \
    --cc=x86@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.