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Date:   Wed, 12 May 2021 15:24:50 -0700
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Subject: Re: [RFC v2 PATCH 7/7] x86/entry: use int for syscall number; handle all invalid syscall nrs
To:     Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Andy Lutomirski <luto@kernel.org>
CC:     Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
From:   "H. Peter Anvin" <hpa@zytor.com>
Message-ID: <C2397A4D-8709-43F9-9967-51538B2B87FE@zytor.com>
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Yes, indeed=2E I hope my reply to Ingo clarifies it as I'm going to try to =
wordsmith that into a better piece of text=2E

On May 12, 2021 3:22:05 PM PDT, Thomas Gleixner <tglx@linutronix=2Ede> wro=
te:
>On Wed, May 12 2021 at 15:09, H=2E Peter Anvin wrote:
>> On 5/12/21 11:34 AM, Thomas Gleixner wrote:
>>>>
>>>> That is intentional, as (again) system calls are int=2E
>>>=20
>>> They are 'int' kernel internally, but _NOT_ at the user space
>visible
>>> side=2E Again: man syscall
>>>=20
>>>      syscall(long number,=2E=2E=2E);
>>>=20
>>> So that results in a user ABI change=2E
>>>=20
>>>> As stated in my reply to Ingo, I'll clean the various descriptions
>and
>>>> try to capture the discussion better=2E
>>>=20
>>> If we agree to go there then this wants to be a seperate commit
>which
>>> does nothing else than changing this behaviour=2E
>>>=20
>>
>> Good idea=2E
>>
>> As far as this being a user ABI change, this is actually a revert to
>the=20
>> original x86-64 ABI; see my message to Ingo=2E
>
>I'm not against that change, but it has to be well justified and the
>reasoning wants to be in the changelog=2E You know the drill :)
>
>Thanks,
>
>        tglx

--=20
Sent from my Android device with K-9 Mail=2E Please excuse my brevity=2E