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From: Tom Gundersen <teg@jklm.no>
Date: Thu, 27 Oct 2016 18:39:51 +0200
Message-ID: <CAG-2HqV2F0_58Wa9VFvonV9V0MDTFiDrxndKkwdFfg2dZy_+0Q@mail.gmail.com>
Subject: Re: [RFC v1 02/14] bus1: provide stub cdev /dev/bus1
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>, Andy Lutomirski <luto@amacapital.net>,
        David Herrmann <dh.herrmann@gmail.com>,
        Hannes Reinecke <hare@suse.com>, Jiri Kosina <jikos@kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Josh Triplett <josh@joshtriplett.org>, Greg KH <greg@kroah.com>,
        Steven Rostedt <rostedt@goodmis.org>
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On Thu, Oct 27, 2016 at 6:37 PM, Linus Torvalds
<torvalds@linux-foundation.org> wrote:
> On Thu, Oct 27, 2016 at 8:25 AM, Tom Gundersen <teg@jklm.no> wrote:
>>
>> Could you elaborate on why you think syscalls would be more
>> appropriate than ioctls?
>
> ioctl's tend to be a horrid mess both for things like compat.but also
> for things like system call tracing and filtering (ie BPF).
>
> The compat mess is fixable by making sure you always use 64-bit fields
> rather than pointers everywhere and everything is aligned.

This we do.

> The
> tracing and filtering one not so much.

Got it. Thanks.

Tom