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Date: Wed, 24 Apr 2024 17:35:46 +0300
From: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
To: Borislav Petkov <bp@alien8.de>
Cc: Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>, 
	Dave Hansen <dave.hansen@linux.intel.com>, x86@kernel.org, "Rafael J. Wysocki" <rafael@kernel.org>, 
	Peter Zijlstra <peterz@infradead.org>, Adrian Hunter <adrian.hunter@intel.com>, 
	Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>, Elena Reshetova <elena.reshetova@intel.com>, 
	Jun Nakajima <jun.nakajima@intel.com>, Rick Edgecombe <rick.p.edgecombe@intel.com>, 
	Tom Lendacky <thomas.lendacky@amd.com>, "Kalra, Ashish" <ashish.kalra@amd.com>, 
	Sean Christopherson <seanjc@google.com>, "Huang, Kai" <kai.huang@intel.com>, Baoquan He <bhe@redhat.com>, 
	kexec@lists.infradead.org, linux-coco@lists.linux.dev, linux-kernel@vger.kernel.org, 
	Tao Liu <ltao@redhat.com>
Subject: Re: [PATCHv10 04/18] cpu/hotplug, x86/acpi: Disable CPU offlining
 for ACPI MADT wakeup
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On Wed, Apr 24, 2024 at 03:50:52PM +0200, Borislav Petkov wrote:
> On Wed, Apr 24, 2024 at 11:38:42AM +0300, Kirill A. Shutemov wrote:
> > It was wrong from beginning. If ACPI MADT wake up method is used on the
> > platform, we cannot handle offline, regardless if it is TDX or not.
> 
> Sounds to me like this fact should be a prominent part of the commit
> message and these 1-4 patches should be carved out as a separate set
> fixing that ACPI MADT thing and I should take them separately now...?
> 
> Also, does this need to go to stable although it is kinda big for
> stable. If stable, do we need a smaller fix first which is backportable?

Correct me, if I am wrong, but I believe TDX guest is the only user of
ACPI MADT wake up method. At least it was added into kernel for TDX guest.
So it wouldn't fix anything user-visible. It might affect a future
platform that uses this wake up method, but it is a guessing game.

-- 
  Kiryl Shutsemau / Kirill A. Shutemov