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Date:   Wed, 12 Jun 2019 15:55:38 +0100
From:   Catalin Marinas <catalin.marinas@arm.com>
To:     Andrey Konovalov <andreyknvl@google.com>
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Subject: Re: [PATCH v17 03/15] arm64: Introduce prctl() options to control
 the tagged user addresses ABI
Message-ID: <20190612145537.GG28951@C02TF0J2HF1T.local>
References: <cover.1560339705.git.andreyknvl@google.com>
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On Wed, Jun 12, 2019 at 01:43:20PM +0200, Andrey Konovalov wrote:
> From: Catalin Marinas <catalin.marinas@arm.com>
> 
> It is not desirable to relax the ABI to allow tagged user addresses into
> the kernel indiscriminately. This patch introduces a prctl() interface
> for enabling or disabling the tagged ABI with a global sysctl control
> for preventing applications from enabling the relaxed ABI (meant for
> testing user-space prctl() return error checking without reconfiguring
> the kernel). The ABI properties are inherited by threads of the same
> application and fork()'ed children but cleared on execve().
> 
> The PR_SET_TAGGED_ADDR_CTRL will be expanded in the future to handle
> MTE-specific settings like imprecise vs precise exceptions.
> 
> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

You need your signed-off-by here since you are contributing it. And
thanks for adding the comment to the TIF definition.

-- 
Catalin