Date:   Mon, 30 Jan 2023 10:14:43 -0500
From:   "Michael S. Tsirkin" <mst@redhat.com>
To:     "Kirill A. Shutemov" <kirill@shutemov.name>
Cc:     Christophe de Dinechin <dinechin@redhat.com>,
        "Reshetova, Elena" <elena.reshetova@intel.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "Shishkin, Alexander" <alexander.shishkin@intel.com>,
        "Shutemov, Kirill" <kirill.shutemov@intel.com>,
        "Kuppuswamy, Sathyanarayanan" <sathyanarayanan.kuppuswamy@intel.com>,
        "Kleen, Andi" <andi.kleen@intel.com>,
        "Hansen, Dave" <dave.hansen@intel.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Peter Zijlstra <peterz@infradead.org>,
        "Wunner, Lukas" <lukas.wunner@intel.com>,
        Mika Westerberg <mika.westerberg@linux.intel.com>,
        Jason Wang <jasowang@redhat.com>,
        "Poimboe, Josh" <jpoimboe@redhat.com>,
        "aarcange@redhat.com" <aarcange@redhat.com>,
        Cfir Cohen <cfir@google.com>, Marc Orr <marcorr@google.com>,
        "jbachmann@google.com" <jbachmann@google.com>,
        "pgonda@google.com" <pgonda@google.com>,
        "keescook@chromium.org" <keescook@chromium.org>,
        James Morris <jmorris@namei.org>,
        Michael Kelley <mikelley@microsoft.com>,
        "Lange, Jon" <jlange@microsoft.com>,
        "linux-coco@lists.linux.dev" <linux-coco@lists.linux.dev>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: Linux guest kernel threat model for Confidential Computing
Message-ID: <20230130101426-mutt-send-email-mst@kernel.org>
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On Mon, Jan 30, 2023 at 03:00:52PM +0300, Kirill A. Shutemov wrote:
> On Mon, Jan 30, 2023 at 12:36:34PM +0100, Christophe de Dinechin wrote:
> > Is there for example anything that precludes TDX or SEV from executing
> > code in the bounce buffers?
> 
> In TDX, attempt to fetch instructions from shared memory (i.e. bounce
> buffer) will cause #GP, only data fetch is allowed. Page table also cannot
> be placed there and will cause the same #GP.

Same with SEV IIRC.

-- 
MST