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Date: Wed, 14 Oct 2015 17:01:55 +0200
From: Ingo Molnar <mingo@kernel.org>
To: Stas Sergeev <stsp@list.ru>
Cc: Andy Lutomirski <luto@kernel.org>, x86@kernel.org,
        linux-kernel@vger.kernel.org, Brian Gerst <brgerst@gmail.com>,
        Denys Vlasenko <dvlasenk@redhat.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Borislav Petkov <bp@alien8.de>, Cyrill Gorcunov <gorcunov@gmail.com>,
        Pavel Emelyanov <xemul@parallels.com>
Subject: Re: [RFC 3/4] x86/signal/64: Re-add support for SS in the 64-bit
 signal context
Message-ID: <20151014150155.GA21330@gmail.com>
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* Stas Sergeev <stsp@list.ru> wrote:

> On an off-topic: there was recently a patch from you that
> disables vm86() by mmap_min_addr. I've found that dosemu, when
> started as root, could override mmap_min_addr. I guess this will
> no longer work, right? Not a big regression, just something to
> know and document.

So I think it should still work, because we check for mmap_min_addr in the system 
call itself:

static long do_sys_vm86(struct vm86plus_struct __user *user_vm86, bool plus)
{
...
        err = security_mmap_addr(0);
        if (err) {
                /*

So if dosemu first tweaks mmap_min_addr, the syscall should succeed.

Thanks,

	Ingo