Re: [PATCH v3 0/4] xfrm: add x86 CONFIG_COMPAT support

[David Miller <davem@davemloft.net>]

From: Patrick McHardy <kaber@trash.net>
Date: Wed, 07 Apr 2010 15:45:51 +0200

> Florian Westphal wrote:
>> David Miller <davem@davemloft.net> wrote:
>>> From: Florian Westphal <fw@strlen.de>
>>> Date: Tue,  6 Apr 2010 00:27:07 +0200
>> 
>> [..]
>> 
>>>> I sent a patch that solved this by adding a sys_compat_write syscall
>>>> and a ->compat_aio_write() to struct file_operations to the
>>>> vfs mailing list, but that patch was ignored by the vfs people,
>>>> and the x86 folks did not exactly like the idea either.
>>>>
>>>> So this leaves three alternatives:
>>>> 1 - drop the whole idea and keep the current status.
>>>> 2 - Add new structure definitions (with new numbering) that would work
>>>>     everywhere, keep the old ones for backwards compatibility (This
>>>>     was suggested by Arnd Bergmann).
> 
> Given that there is only a quite small number of users of this
> interface, that would in my opinion be the best way.

Can you explain that line of reasoning?

It's not that there are only "3 or 4 tools" using these interfaces,
it's the fact that 32-bit binaries of those tools are on millions and
millions of systems out there.