[PATCH v17 03/15] arm64: Introduce prctl() options to control the tagged user addresses ABI

[Andrey Konovalov]

On Wed, Jun 12, 2019 at 1:43 PM Andrey Konovalov <andreyknvl at google.com> wrote:
>
> From: Catalin Marinas <catalin.marinas at 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 at arm.com>

Catalin, would you like to do the requested changes to this patch
yourself and send it to me or should I do that?