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Subject: Re: [PATCH 0/3] PTI for x86-32 Fixes and Updates
To:     Josh Poimboeuf <jpoimboe@redhat.com>, Pavel Machek <pavel@ucw.cz>
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Message-ID: <f654c085-d07c-5047-0d59-e2f88b00e921@intel.com>
Date:   Mon, 23 Jul 2018 15:07:13 -0700
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On 07/23/2018 02:59 PM, Josh Poimboeuf wrote:
> On Mon, Jul 23, 2018 at 11:38:30PM +0200, Pavel Machek wrote:
>> But for now I'd like at least "global" option of turning pti on/off
>> during runtime for benchmarking. Let me see...
>>
>> Something like this, or is it going to be way more complex? Does
>> anyone have patch by chance?
> RHEL/CentOS has a global PTI enable/disable, which uses stop_machine().

Let's not forget PTI's NX-for-userspace in the kernel page tables.  That
provides Spectre V2 mitigation as well as Meltdown.