Re: stop breaking dosemu (Re: x86/kconfig/32: Rename CONFIG_VM86 and default it to 'n')

[Stas Sergeev <stsp@list.ru>]

05.09.2015 01:46, Raymond Jennings пишет:
> On 09/04/15 14:30, Stas Sergeev wrote:
>> 05.09.2015 00:16, Stas Sergeev пишет:
>>> I agree. vm86() is a mess.
>>> My point is that its risky parts and useless funtionality
>>> is _already_ known (even I can point to the particular code
>>> parts than can simply be removed). As such, it simply had
>>> to be re-visited and cleaned up to match at least 1 and 3
>>> (and then maybe 5). This wasn't done, and the knob was
>>> introduced _instead_ of doing this.
>> Grr, I mean it was disabled by default instead of doing this,
>> and the knob was only proposed, not added.
>
> You can't just pull vm86 out of the kernel anyway.  dosemu is a 
> userspace application that depends on it, so pulling this feature out 
> would be a big fat regression, period.
>
> I would personally rather not hear about how "it's a legacy program so 
> its userbase is shrinking" used as any sort of excuse to ignore the 
> fact that we shouldn't break userspace.
>
> I can even say as a user that vm86 is important to me.
>
> By all means, cleaning up vm86 is a good idea.  But removing it or 
> fencing it off with a strong deprecation doesn't sound like the right 
> idea.
Yes, that's what I was saying lengthy.
Fencing it off may help those who does not use it,
and that's what most people here worry about.
BUT it will also do a big harm to those who uses it,
unless done properly like for modify_ldt(), or *sigh*
just with mmap_min_addr.