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Date:   Tue, 28 Sep 2021 16:24:34 +0200
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From:   Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To:     Ard Biesheuvel <ardb@kernel.org>
Cc:     linux-efi <linux-efi@vger.kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [PATCH 1/2] efi: Disable runtime services on RT
Message-ID: <20210928142434.uqhkd3ribja6j654@linutronix.de>
References: <20210924134919.1913476-1-bigeasy@linutronix.de>
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On 2021-09-28 15:34:47 [+0200], Ard Biesheuvel wrote:
> Are you sure you want to disable EFI runtime services on all x86
> systems with PREEMPT_RT as well?

The only problem that I am aware of is that you need to reboot with
enabled runtime service (via bootargs, #2) in order to alter boot loader
settings.
I'm not aware of any other shortcomings. There are no guarantees how
long an EFI service routine may take.
That patch is in the RT queue since v4.18-rc8-rt1.

Sebastian