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Date: Mon, 27 Jul 2015 11:36:10 -0400
From: Boris Ostrovsky <boris.ostrovsky@oracle.com>
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To: Andy Lutomirski <luto@kernel.org>, Peter Zijlstra <peterz@infradead.org>,
        Steven Rostedt <rostedt@goodmis.org>
CC: "security@kernel.org" <security@kernel.org>, X86 ML <x86@kernel.org>,
        Borislav Petkov <bp@alien8.de>, Sasha Levin <sasha.levin@oracle.com>,
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        Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
        Andrew Cooper <andrew.cooper3@citrix.com>,
        Jan Beulich <jbeulich@suse.com>, xen-devel <xen-devel@lists.xen.org>
Subject: Re: [PATCH v4 0/3] x86: modify_ldt improvement, test, and config
 option
References: <cover.1437802102.git.luto@kernel.org>
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On 07/25/2015 01:36 AM, Andy Lutomirski wrote:
> Here's v3.  It fixes the "dazed and confused" issue, I hope.  It's also
> probably a good general attack surface reduction, and it replaces some
> scary code with IMO less scary code.
>
> Also, servers and embedded systems should probably turn off modify_ldt.
> This makes that possible.
>
> Xen people, can you take a look at this?
>
> Willy and Kees: I left the config option alone.  The -tiny people will
> like it, and we can always add a sysctl of some sort later.
>
> Changes from v3:
>   - Hopefully fixed Xen.

32b-on-32b fails in the same manner. (but non-zero LDT is taken care of)

>   - Fixed 32-bit test case on 32-bit native kernel.

I am not sure I see what changed.

-boris