From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Cooper <andrew.cooper3@citrix.com>
Subject: Re: Possible problem emulating movntq, movss
Date: Wed, 06 Aug 2014 10:22:00 +0100
Message-ID: <53E1F3B8.9090103@citrix.com>
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To: Razvan Cojocaru <rcojocaru@bitdefender.com>, "xen-devel@lists.xen.org" <xen-devel@lists.xen.org>
Cc: keir@xen.org, Jan Beulich <JBeulich@suse.com>
List-Id: xen-devel@lists.xenproject.org

On 06/08/2014 09:57, Razvan Cojocaru wrote:
> Hello,
>
> We found that our HVM guests froze when trying to emulate movntq
> instructions. The solution seems to be to replace "goto done;" with
> "break;" at line 4191 (when handling "case 0x7f:") in
> xen/arch/x86/x86_emulate/x86_emulate.c. Otherwise the writeback part
> doesn't happen.
>
> If you're happy with the fix I can prepare a patch, otherwise please let
> me know if we're missing something.
>
>
> Thanks,
> Razvan Cojocaru

I can't comment on the fix right now, but will take a look at it in due
course.

If you are making a change, please can you add a testcase for movntq and
movss to tools/tests/x86_emulator/test_x86_emulator.c which is the
unittest harness for x86_emulate.

~Andrew