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From:   Catalin Marinas <catalin.marinas@arm.com>
To:     Will Deacon <will@kernel.org>, Mark Brown <broonie@kernel.org>
Cc:     linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        David Spickett <David.Spickett@arm.com>
Subject: Re: [PATCH v2] arm64/ptrace: Ensure that the task sees ZT writes on first use
Date:   Thu, 17 Aug 2023 19:54:37 +0100
Message-Id: <169229846428.1184154.5773484111290413905.b4-ty@arm.com>
In-Reply-To: <20230816-arm64-zt-ptrace-first-use-v2-1-00aa82847e28@kernel.org>
References: <20230816-arm64-zt-ptrace-first-use-v2-1-00aa82847e28@kernel.org>
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On Wed, 16 Aug 2023 19:40:07 +0100, Mark Brown wrote:
> When the value of ZT is set via ptrace we don't disable traps for SME.
> This means that when a the task has never used SME before then the value
> set via ptrace will never be seen by the target task since it will
> trigger a SME access trap which will flush the register state.
> 
> Disable SME traps when setting ZT, this means we also need to allocate
> storage for SVE if it is not already allocated, for the benefit of
> streaming SVE.
> 
> [...]

Applied to arm64 (for-next/fixes), thanks!

[1/1] arm64/ptrace: Ensure that the task sees ZT writes on first use
      https://git.kernel.org/arm64/c/2f43f549cd0b

-- 
Catalin