MIME-Version: 1.0
In-Reply-To: <20170329165554.GA24250@redhat.com>
References: <20170328145413.GA3164@redhat.com> <20170329163335.GA23977@redhat.com>
 <CA+55aFy1Dayhmw0r8syRPBJo+10EOfPmeCTTTxzcLiQRrG69jg@mail.gmail.com> <20170329165554.GA24250@redhat.com>
From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Wed, 29 Mar 2017 09:59:38 -0700
Message-ID: <CA+55aFzbbLZaWvg+vTEKrfzZkwb=iAVUK5cZu2LxdbevZiGJ2g@mail.gmail.com>
Subject: Re: syscall_get_error() && TS_ checks
To: Oleg Nesterov <oleg@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
        Andy Lutomirski <luto@kernel.org>,
        Denys Vlasenko <dvlasenk@redhat.com>, "H. Peter Anvin" <hpa@zytor.com>,
        Ingo Molnar <mingo@redhat.com>,
        Jan Kratochvil <jan.kratochvil@redhat.com>,
        Pedro Alves <palves@redhat.com>, Thomas Gleixner <tglx@linutronix.de>,
        "the arch/x86 maintainers" <x86@kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Content-Type: text/plain; charset=UTF-8
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 711
Lines: 16

On Wed, Mar 29, 2017 at 9:55 AM, Oleg Nesterov <oleg@redhat.com> wrote:
>
> Once again, it is only used in arch/x86/kernel/signal.c by do_signal() and
> handle_signal(). We do not care if mmap() returns a valid pointer with the
> high bit set, regs-ax can't be confused with -ERESTART code.

Immaterial. If the function is called "get_error()", it sure as hell
shouldn't return a random non-error value.

Code should make sense, otherwise it's not going to be maintainable.
Naming matters. If the code doesn't match the name of the function,
that's a bug regardless of whether it has semantic effects or not in
the end - because somebody will eventually depend on the _expected_
semantics.

              Linus