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From: =?utf-8?Q?Llu=C3=ADs_Vilanova?= <vilanova@ac.upc.edu>
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Date: Mon, 26 Jun 2017 15:04:25 +0300
In-Reply-To: <CAFEAcA8VqE13i3BBs34KSh6cY=McxP=CmxU8nXpp4WaPTSLiRg@mail.gmail.com>
	(Peter Maydell's message of "Mon, 26 Jun 2017 10:32:37 +0100")
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Subject: Re: [Qemu-devel] Tracing guest virtual addresses
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To: Peter Maydell <peter.maydell@linaro.org>
Cc: Alex =?utf-8?Q?Benn=C3=A9e?= <alex.bennee@linaro.org>, Jayanto Minocha <jayanto@gmail.com>, QEMU Developers <qemu-devel@nongnu.org>

Peter Maydell writes:

> On 26 June 2017 at 10:26, Llu=C3=ADs Vilanova <vilanova@ac.upc.edu> wrote:
>> There's two places where memory access tracing is triggered:
>>=20
>> * tcg_gen_qemu_ld/st_...
>> * ld/st templates (both softmmu and user)
>>=20
>> AFAIK, helpers use the ld/st templates to access guest memory.

> Mostly, but there are one or two special cases, for instance
> the ARM HELPER(dc_zva) in target/arm/helper.c, which has a
> fastpath that uses tlb_vaddr_to_host to look up the host memory
> address and then memset to do the clear-to-zeroes operation.

Should that be replaced with a cpu_memset or similar?

Cheers,
  Lluis