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Date:   Sat, 25 Mar 2023 09:20:47 -0700
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Subject: Re: [PATCH] x86: Disable kexec for TDX guests
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To:     "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Borislav Petkov <bp@alien8.de>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, x86@kernel.org,
        Eric Biederman <ebiederm@xmission.com>,
        kexec@lists.infradead.org, linux-kernel@vger.kernel.org
References: <20230325160128.21857-1-kirill.shutemov@linux.intel.com>
From:   Dave Hansen <dave.hansen@intel.com>
In-Reply-To: <20230325160128.21857-1-kirill.shutemov@linux.intel.com>
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On 3/25/23 09:01, Kirill A. Shutemov wrote:
> The last item is tricky. TDX guests use ACPI MADT MPWK to bring up
> secondary CPUs. The mechanism doesn't allow to put a CPU back offline if
> it has woken up.

I'm not sure I like this approach.

TDX uses the MADT exclusively.

MADT-based systems can't offline CPUs.

kexec() requires