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From:   Thomas Gleixner <tglx@linutronix.de>
To:     Andy Lutomirski <luto@kernel.org>
Cc:     Sasha Levin <sashal@kernel.org>,
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Subject: Re: [PATCH v13 00/16] Enable FSGSBASE instructions
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Andy Lutomirski <luto@kernel.org> writes:
> Is there a plan to deal with:
>
>         /*
>          * This function has some ABI oddities.
>          *
>          * A 32-bit ptracer probably expects that writing FS or GS will change
>          * FSBASE or GSBASE respectively.  In the absence of FSGSBASE support,
>          * this code indeed has that effect.  When FSGSBASE is added, this
>          * will require a special case.
>          *
>          * For existing 64-bit ptracers, writing FS or GS *also* currently
>          * changes the base if the selector is nonzero the next time the task
>          * is run.  This behavior may? not be needed, and trying to preserve it
>          * when FSGSBASE is added would be complicated at best.
>          */
>
> in arch/x86/kernel/ptrace.c?

Not that I'm aware of.