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Date: Fri, 20 Oct 2017 19:39:53 +0100
From: Alan Cox <gnomes@lxorguk.ukuu.org.uk>
To: Brijesh Singh <brijesh.singh@amd.com>
Cc: x86@kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
        Borislav Petkov <bp@alien8.de>, Tom Lendacky <thomas.lendacky@amd.com>,
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        "H. Peter Anvin" <hpa@zytor.com>, Borislav Petkov <bp@suse.de>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        David Laight <David.Laight@ACULAB.COM>, Arnd Bergmann <arnd@arndb.de>
Subject: Re: [Part1 PATCH v7 13/17] x86/io: Unroll string I/O when SEV is
 active
Message-ID: <20171020193953.7814f013@alans-desktop>
In-Reply-To: <20171020143059.3291-14-brijesh.singh@amd.com>
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        <20171020143059.3291-14-brijesh.singh@amd.com>
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On Fri, 20 Oct 2017 09:30:55 -0500
Brijesh Singh <brijesh.singh@amd.com> wrote:

> From: Tom Lendacky <thomas.lendacky@amd.com>
> 
> Secure Encrypted Virtualization (SEV) does not support string I/O, so
> unroll the string I/O operation into a loop operating on one element at
> a time.

Does this also mean that any firmware running in the virtual machine
(EFI, BIOS, VGA etc) has to be patched and if so shouldn't that be
documented somewhere ?

Alan