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Date:   Fri, 13 Nov 2020 18:26:24 -0600
From:   Segher Boessenkool <segher@kernel.crashing.org>
To:     Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Cc:     Nick Desaulniers <ndesaulniers@google.com>,
        Alexandre Chartre <alexandre.chartre@oracle.com>,
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        kernel test robot <lkp@intel.com>,
        Arvind Sankar <nivedita@alum.mit.edu>,
        Ard Biesheuvel <ardb@kernel.org>
Subject: Re: [RFC][PATCH 21/24] x86/entry: Disable stack-protector for IST entry C handlers
Message-ID: <20201114002624.GX2672@gate.crashing.org>
References: <20201109144425.270789-22-alexandre.chartre@oracle.com> <202011131552.4kvOb9Id-lkp@intel.com> <CAKwvOdnvhyNs1arkVO1=pw9GB9NePKUfQYAY+Q0Ur9Qe9HJ37w@mail.gmail.com> <20201113234701.GV2672@gate.crashing.org> <CANiq72nKMd_BOOowqowLAn0PZ5tu7X8G=8OrpG34qYHGLDGw6Q@mail.gmail.com>
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On Sat, Nov 14, 2020 at 01:01:42AM +0100, Miguel Ojeda wrote:
> On Sat, Nov 14, 2020 at 12:48 AM Segher Boessenkool
> <segher@kernel.crashing.org> wrote:
> >
> > Like *all* GCC extensions.
> 
> They might not be standard, but they may be portable enough for the
> compilers we care about.

Sure, they may be portable enough for some specific purpose :-)

But you cannot limit yourself to the greatest common denominator: the
kernel wants to use many features only available on newer compiler
versions, too; this is no different.


Segher