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Subject: Re: [PATCH v26 26/30] ELF: Introduce arch_setup_elf_property()
To:     Matthew Wilcox <willy@infradead.org>
Cc:     Borislav Petkov <bp@alien8.de>, x86@kernel.org,
        "H. Peter Anvin" <hpa@zytor.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, linux-kernel@vger.kernel.org,
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        linux-arch@vger.kernel.org, linux-api@vger.kernel.org,
        Arnd Bergmann <arnd@arndb.de>,
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        Balbir Singh <bsingharora@gmail.com>,
        Cyrill Gorcunov <gorcunov@gmail.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Eugene Syromiatnikov <esyr@redhat.com>,
        Florian Weimer <fweimer@redhat.com>,
        "H.J. Lu" <hjl.tools@gmail.com>, Jann Horn <jannh@google.com>,
        Jonathan Corbet <corbet@lwn.net>,
        Kees Cook <keescook@chromium.org>,
        Mike Kravetz <mike.kravetz@oracle.com>,
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        Peter Zijlstra <peterz@infradead.org>,
        Randy Dunlap <rdunlap@infradead.org>,
        "Ravi V. Shankar" <ravi.v.shankar@intel.com>,
        Vedvyas Shanbhogue <vedvyas.shanbhogue@intel.com>,
        Dave Martin <Dave.Martin@arm.com>,
        Weijiang Yang <weijiang.yang@intel.com>,
        Pengfei Xu <pengfei.xu@intel.com>,
        Haitao Huang <haitao.huang@intel.com>,
        Mark Brown <broonie@kernel.org>,
        Catalin Marinas <catalin.marinas@arm.com>
References: <20210427204315.24153-1-yu-cheng.yu@intel.com>
 <20210427204315.24153-27-yu-cheng.yu@intel.com> <YKVUgzJ0MVNBgjDd@zn.tnic>
 <c29348d8-caae-5226-d095-ae3992d88338@intel.com>
 <YKaesoXCSBmCwD+4@casper.infradead.org>
From:   "Yu, Yu-cheng" <yu-cheng.yu@intel.com>
Message-ID: <89be0683-e1b3-d843-c4b4-ba351ede7427@intel.com>
Date:   Thu, 20 May 2021 10:52:15 -0700
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On 5/20/2021 10:38 AM, Matthew Wilcox wrote:
> On Wed, May 19, 2021 at 03:14:58PM -0700, Yu, Yu-cheng wrote:
>>>> +++ b/include/uapi/linux/elf.h
>>>> @@ -455,4 +455,13 @@ typedef struct elf64_note {
>>>>    /* Bits for GNU_PROPERTY_AARCH64_FEATURE_1_BTI */
>>>>    #define GNU_PROPERTY_AARCH64_FEATURE_1_BTI	(1U << 0)
>>>> +/* .note.gnu.property types for x86: */
>>>> +#define GNU_PROPERTY_X86_FEATURE_1_AND		0xc0000002
>>>
>>> Why not 0xc0000001? ARM64 is 0xc0000000...
>>>
>>
>> I just looked at the ABI document.
>>
>> ARM has GNU_PROPERTY_AARCH64_FEATURE_1_AND 0xc0000000
>>
>> X86 has:
>> 	GNU_PROPERTY_X86_ISA_1_USED	0xc0000000
>> 	GNU_PROPERTY_X86_ISA_1_NEEDED	0xc0000001
>> 	GNU_PROPERTY_X86_FEATURE_1_AND	0xc0000002
> 
> Please add all three, not just the last one.
> 

Ok!