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	Wed, 19 Jul 2023 16:20:33 +0100
Date: Wed, 19 Jul 2023 16:20:33 +0100
Message-ID: <86v8egszb2.wl-maz@kernel.org>
From: Marc Zyngier <maz@kernel.org>
To: Fuad Tabba <tabba@google.com>
Cc: kvmarm@lists.linux.dev,
	oliver.upton@linux.dev,
	catalin.marinas@arm.com,
	james.morse@arm.com,
	suzuki.poulose@arm.com,
	yuzenghui@huawei.com,
	will@kernel.org
Subject: Re: [PATCH v1 0/5] Fix setting SVE and SME traps in (h)VHE
In-Reply-To: <20230719150639.1968034-1-tabba@google.com>
References: <20230719150639.1968034-1-tabba@google.com>
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Hey Fuad,

Many thanks for looking into this, much appreciated. A passing comment
below.

On Wed, 19 Jul 2023 16:06:34 +0100,
Fuad Tabba <tabba@google.com> wrote:
> 
> The (re)setting and disabling of SVE/SME trap handling (mostly)
> done for the hVHE work [*] misses a couple of cases.
> 
> This patch series ensures that these traps are disabled on setup
> and reset. Moreover, it makes the code consistent in using
> CPACR_EL1 or CPTR_EL2, depending on the mode.

To provide context, this last point isn't really a correctness issue.
It only ensures that:

- we don't need to issue a synchronisation when alternating one or the
  other accessor,

- when running hVHE under NV, we don't trap unnecessarily on accessing
  CPTR_EL2, while CPACR_EL1 can be used directly without any trap.

I'll have a look at the actual patches shortly.

Thanks again,

	M.

-- 
Without deviation from the norm, progress is not possible.