Message-ID: <f32f1f77-c707-ae19-ae1a-dc0a37fa9806@intel.com>
Date:   Fri, 24 Feb 2023 07:22:18 -0800
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Subject: Re: [PATCH 0/2] Kexec enabling in TDX guest
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To:     "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        David Woodhouse <dwmw2@infradead.org>
Cc:     Borislav Petkov <bp@alien8.de>,
        Kuppuswamy Sathyanarayanan 
        <sathyanarayanan.kuppuswamy@linux.intel.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Isaku Yamahata <isaku.yamahata@intel.com>, x86@kernel.org,
        linux-coco@lists.linux.dev, kexec@lists.infradead.org,
        linux-kernel@vger.kernel.org
References: <20230213234836.3683-1-kirill.shutemov@linux.intel.com>
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 <20230224143004.xqhpv6upn2fkqkjp@box.shutemov.name>
From:   Dave Hansen <dave.hansen@intel.com>
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On 2/24/23 06:30, Kirill A. Shutemov wrote:
> Ideally, it has to be addressed on BIOS level: it has to provide a way to
> offline CPUs, putting it back to pre-wakeup state.

Is there anything stopping us from just parking the CPUs in a loop
looking at 'acpi_mp_wake_mailbox_paddr'?  Basically park them in a way
which is indistinguishable from what the BIOS did.