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Date:   Fri, 20 Aug 2021 12:19:50 +0200
From:   'Joerg Roedel' <joro@8bytes.org>
To:     David Laight <David.Laight@aculab.com>
Cc:     "x86@kernel.org" <x86@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        "hpa@zytor.com" <hpa@zytor.com>, Joerg Roedel <jroedel@suse.de>,
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        Andy Lutomirski <luto@kernel.org>,
        Uros Bizjak <ubizjak@gmail.com>,
        Arvind Sankar <nivedita@alum.mit.edu>,
        Ard Biesheuvel <ardb@kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Fabio Aiuto <fabioaiuto83@gmail.com>,
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Subject: Re: [PATCH] x86/efi: Restore Firmware IDT in before
 ExitBootServices()
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On Fri, Aug 20, 2021 at 09:02:46AM +0000, David Laight wrote:
> So allocate and initialise the Linux IDT - so entries can be added.
> But don't execute 'lidt' until later on.

The IDT is needed in this path to handle #VC exceptions caused by CPUID
instructions. So loading the IDT later is not an option.

Regards,

	Joerg