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From:   Florian Weimer <fweimer@redhat.com>
To:     Dave Hansen <dave.hansen@intel.com>
Cc:     "Edgecombe, Rick P" <rick.p.edgecombe@intel.com>,
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Subject: Re: [PATCH v2 01/39] Documentation/x86: Add CET description
References: <20220929222936.14584-1-rick.p.edgecombe@intel.com>
        <20220929222936.14584-2-rick.p.edgecombe@intel.com>
        <87ilkr27nv.fsf@oldenburg.str.redhat.com>
        <62481017bc02b35587dd520ed446a011641aa390.camel@intel.com>
        <87v8opz0me.fsf@oldenburg.str.redhat.com>
        <e3c3d68d-ce99-a70a-1026-0ba99520ae57@intel.com>
Date:   Wed, 12 Oct 2022 18:54:06 +0200
In-Reply-To: <e3c3d68d-ce99-a70a-1026-0ba99520ae57@intel.com> (Dave Hansen's
        message of "Wed, 12 Oct 2022 08:59:51 -0700")
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* Dave Hansen:

> On 10/12/22 05:29, Florian Weimer wrote:
>>> What did you think of the proposal to disable existing binaries and
>>> start from scratch? Elaborated in the coverletter in the section
>>> "Compatibility of Existing Binaries/Enabling Interface".
>> The ABI was finalized around four years ago, and we have shipped several
>> Fedora and Red Hat Enterprise Linux versions with it.  Other
>> distributions did as well.  It's a bit late to make changes now, and
>> certainly not for such trivialities. 
>
> Just to be clear: You're saying that a user/kernel ABI was "finalized"
> by glibc shipping the user side of it, before there being an upstream
> kernel implementation?

Sorry for being unclear.  I was refering to the x86-64 ELF psABI
supplement for CET, not the kernel/userspace interface, which still does
not exist in its final form as of today, as far as I understand it.

Thanks,
Florian