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Date: Wed, 3 Jun 2015 19:21:47 +0200
From: Ingo Molnar <mingo@kernel.org>
To: Andy Lutomirski <luto@amacapital.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Denys Vlasenko <dvlasenk@redhat.com>, Brian Gerst <brgerst@gmail.com>,
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        Linus Torvalds <torvalds@linux-foundation.org>,
        Oleg Nesterov <oleg@redhat.com>, Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [RFC PATCH 0/7] x86/entry: Create a home for the x86 entry code
 in arch/x86/entry/
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* Ingo Molnar <mingo@kernel.org> wrote:

> 
> * Andy Lutomirski <luto@amacapital.net> wrote:
> 
> > On Wed, Jun 3, 2015 at 10:11 AM, Ingo Molnar <mingo@kernel.org> wrote:
> > >
> > > * H. Peter Anvin <hpa@zytor.com> wrote:
> > >
> > >> I like the patch set (and you can add my Acked-by:) *except* 7/7, and the reason
> > >> for that is that it really isn't entry code, it is user space code.
> > >
> > > Well, I think arch/x86/entry/ should be a broader category for all things entry
> > > code: and the vsyscall code is closely related to the syscall entry/exit code so
> > > it's in a better place there than just being in the generic arch/x86/kernel/
> > > directory.
> > >
> > > I kept it separate in arch/x86/entry/vsyscall/ so it doesn't mix with other entry
> > > code.
> > 
> > ...and my reading comprehension is way off this morning.  You already called it 
> > arch/x86/entry, so there was no reason for me to suggest that :)
> > 
> > Anyway, arch/x86/entry/vdso isn't so bad.  It's just a bit odd sounding to me.
> 
> We could make it arch/x86/sys/? Sounds a bit too generic though.
> 
> Didn't want to limit it to system calls only, because there's various other 
> entry methods (irqs, traps, NMI, etc.) that we want to handle in a coherent 
> fashion. [ Which you are intimately aware of ;-) ]

Another tweak would be to move the kernel side entry code into 
arch/x86/entry/system/ or so, to create the following organization:

    arch/x86/entry:            all things entry methods

    arch/x86/entry/system/:    system/kernel mode entry code
    arch/x86/entry/vdso/:      user mode entry code
    arch/x86/entry/vsyscall/:  [legacy vsyscall entry code]

    arch/x86/entry/syscalls/:  build-time syscall table generation code

My primary goal is to have them all close to each other, so that we can have 
better structure, more coherency and easier overview. The names are negotiable, 
the concept is not ;-)

Thanks,

	Ingo