Date: Tue, 25 Nov 2014 10:10:32 -0800
From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
To: David Miller <davem@davemloft.net>
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Subject: Re: [PATCH v4 0/7] kernel tinification: optionally compile out
 splice family of syscalls (splice, vmsplice, tee and sendfile)
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On Tue, Nov 25, 2014 at 12:13:05PM -0500, David Miller wrote:
> From: Randy Dunlap <rdunlap@infradead.org>
> Date: Tue, 25 Nov 2014 08:17:58 -0800
> 
> > Is the splice family of syscalls the only one that tiny has identified
> > for optional building or can we expect similar treatment for other
> > syscalls?
> > 
> > Why will many embedded systems not need these syscalls?  You know
> > exactly what apps they run and you are positive that those apps do
> > not use splice?
> 
> I think starting to compile out system calls is a very slippery
> slope we should not begin the journey down.
> 
> This changes the forward facing interface to userspace.

I certainly sympathize with this concern, given the importance of software
portability.  However, the tiny-hardware alternative appears ot some sort
of special-purpose embedded OS, which most definitely will suffer from
software compatibility issues.  I guess that the good news is that much
of the tiny hardware that used to be 8 or 16 bits is now 32 bits, which
means that it has at least some chance of running some form of Linux.  ;-)

							Thanx, Paul