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Subject: Re: [PATCH 10/10] mm: Prevent munmap and remap_file_pages of shadow
 stack
From: Yu-cheng Yu <yu-cheng.yu@intel.com>
To: Andy Lutomirski <luto@kernel.org>
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Date: Thu, 07 Jun 2018 13:15:01 -0700
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On Thu, 2018-06-07 at 11:50 -0700, Andy Lutomirski wrote:
> On Thu, Jun 7, 2018 at 7:41 AM Yu-cheng Yu <yu-cheng.yu@intel.com> wrote:
> 
> blocking remap_file_pages() seems reasonable.  I'm not sure what's
> wrong with munmap().

Yes, maybe we don't need to block munmap().  If the shadow stack is
unmapped, the application gets a fault.  I will remove the patch.