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Subject: Re: [PATCH v29 25/32] x86/cet/shstk: Handle thread shadow stack
To:     Borislav Petkov <bp@alien8.de>, "H.J. Lu" <hjl.tools@gmail.com>
CC:     the arch/x86 maintainers <x86@kernel.org>,
        "H. Peter Anvin" <hpa@zytor.com>,
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        Pengfei Xu <pengfei.xu@intel.com>,
        Haitao Huang <haitao.huang@intel.com>,
        Rick P Edgecombe <rick.p.edgecombe@intel.com>
References: <20210820181201.31490-1-yu-cheng.yu@intel.com>
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From:   "Yu, Yu-cheng" <yu-cheng.yu@intel.com>
Message-ID: <47a73ab7-20c9-f7bb-14b0-ba81e33fa1ad@intel.com>
Date:   Thu, 26 Aug 2021 10:33:03 -0700
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On 8/26/2021 10:28 AM, Borislav Petkov wrote:
> On Thu, Aug 26, 2021 at 10:22:29AM -0700, H.J. Lu wrote:
>>>> +     /*
>>>> +      * Earlier clone() does not pass stack_size.  Use RLIMIT_STACK and
>>>
>>> What is "earlier clone()"?
>>
>> clone() doesn't have stack size info which was added to clone3().
> 
> /me goes and reads the manpage...
> 
>     clone3()
>         The  clone3()  system call provides a superset of the functionality of the older
>         clone() interface.  It also provides a number of  API  improvements,  including:
>         space  for additional flags bits; cleaner separation in the use of various argu‐
>         ments; and the ability to specify the size of the child's stack area.
> 
> Aha, Yu-cheng, pls use those words to make your comment understandable.
> 
> Thx.
> 

Sure!

Yu-cheng