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From: Peter Maydell <peter.maydell@linaro.org>
Date: Thu, 23 Oct 2014 17:25:22 +0100
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Subject: Re: [Qemu-devel] [PATCH] arm: fix TB alignment check
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To: Richard Henderson <rth@twiddle.net>
Cc: =?UTF-8?B?QWxleCBCZW5uw6ll?= <alex.bennee@linaro.org>, QEMU Developers <qemu-devel@nongnu.org>, Kirill Batuzov <batuzovk@ispras.ru>, maria.klimushenkova@ispras.ru, Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru>, Paolo Bonzini <pbonzini@redhat.com>, =?UTF-8?B?0JTQtdC90LjRgSDQlNC80LjRgtGA0LjQtdCy?= <zealot351@gmail.com>, Leon Alrae <leon.alrae@imgtec.com>

On 23 October 2014 17:15, Richard Henderson <rth@twiddle.net> wrote:
> [1] Why 32 when the maximum insn size is more like 15 bytes, I don't know.  But
> it likely doesn't matter since I'd expect such large TB's to fill up the opcode
> buffer first.  There would have to be a lot of nops on that page.

Do we actually correctly GPF if the guest hands us an instruction
with a huge long set of prefix bytes? I can't see anything obviously
in the code that catches this case...

-- PMM