[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <559C8BFE.6050604@linux.intel.com>
Date: Tue, 07 Jul 2015 19:33:34 -0700
From: Arjan van de Ven <arjan@...ux.intel.com>
To: Andy Lutomirski <luto@...nel.org>, x86@...nel.org,
linux-kernel@...r.kernel.org
CC: Oleg Nesterov <oleg@...hat.com>, Kees Cook <keescook@...omium.org>,
Peter Zijlstra <peterz@...radead.org>,
Borislav Petkov <bp@...en8.de>,
Linus Torvalds <torvalds@...ux-foundation.org>
Subject: Re: [PATCH] x86/kconfig/32: Mark CONFIG_VM86 as BROKEN
On 7/7/2015 6:25 PM, Andy Lutomirski wrote:
> VM86 is entirely broken if ptrace, syscall auditing, or NOHZ_FULL is
> in use. The code is a big undocumented mess, it's a real PITA to
> test, and it looks like a big chunk of vm86_32.c is dead code. It
> also plays awful games with the entry asm.
>
> No one should be using it anyway. Use DOSBOX or KVM instead.
>
> Mark it BROKEN. I want to remove some (obviously incorrect) exit
> asm that it depends on, and I don't want to figure out how to run
> severely obsolete programs just to test something that no one uses
> for anything other than exploits anyway.
>
while it is never great to deprecate features, in this case I am not sure
there is another choice unless someone steps up to seriously revamp this code.
(and look at it from a PREEMPT, NO_HZ etc etc angle)
if this patch would not be acceptable, at minimum we need some sort of "off by default
unless the sysadmin flips a sysfs thing", which is really just a huge hack.
so for me this is
Acked-by: Arjan van de Ven <arjan@...ux.intel.com>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists