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Date: Wed, 12 Jun 2024 12:46:37 +0300
From: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
To: Jeremi Piotrowski <jpiotrowski@linux.microsoft.com>
Cc: Chris Oo <cho@microsoft.com>, Dave Hansen <dave.hansen@intel.com>, 
	Dave Hansen <dave.hansen@linux.intel.com>, Thomas Gleixner <tglx@linutronix.de>, 
	Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>, 
	"x86@kernel.org" <x86@kernel.org>, "H. Peter Anvin" <hpa@zytor.com>, 
	"linux-coco@lists.linux.dev" <linux-coco@lists.linux.dev>, "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>, 
	Dexuan Cui <decui@microsoft.com>, John Starks <John.Starks@microsoft.com>
Subject: Re: [EXTERNAL] Re: [PATCH] x86/tdx: Generate SIGBUS on userspace MMIO
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On Tue, Jun 11, 2024 at 07:25:27PM +0200, Jeremi Piotrowski wrote:
> Is there a reason we can't fix the handler to do the #VE->mmio emulation
> for userspace too, so that this scenario works just like outside of a
> CVM?

We are looking into it. It requires some groundwork to properly understand
risks of wider attack surface. I think we will get there, but it will take time.

-- 
  Kiryl Shutsemau / Kirill A. Shutemov