From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.8]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EEBD2171D0 for ; Tue, 21 Nov 2023 09:31:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="WTjsZ5gf" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1700559073; x=1732095073; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=bzOd0cd2+5cL6VwtiHKsX8WwvIE2qYTC6osgFynenks=; b=WTjsZ5gfh8LKJ0ME4j4IWeZfHck366TlCkieWU39Fa0r4Tw29Gt3zuMT pjLRAgf1yS1TGEpcrz4fT1HlPVa0VWSOjaZTmwWtKDMPtRaHQLno2ZkFZ SZiS4XLKJ/cSCy2pxDSYBS2TqhJrx8YxPHiP1a7FU+lT7QtPZKR79+lfV GyxC/HPSql1S1yPyZ7UVEfoX+iEWYx6SU/uvQ6VageNOPgcC7wLr3EVVa a7lfjQQcz1h6L/VTcVl/LlPU3AJP0/nIK0w5TqW9k3iKMEWPdcSRy8SCc KQWJ0LvTYjaqV97jRPMmO+MnmJg400bDrkgx/xPEZYYhbOArRiH+unAFd w==; X-IronPort-AV: E=McAfee;i="6600,9927,10900"; a="4930136" X-IronPort-AV: E=Sophos;i="6.04,215,1695711600"; d="scan'208";a="4930136" Received: from fmviesa002.fm.intel.com ([10.60.135.142]) by fmvoesa102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Nov 2023 01:31:12 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.04,215,1695711600"; d="scan'208";a="8023791" Received: from ikosarev-mobl1.ger.corp.intel.com (HELO box.shutemov.name) ([10.252.40.84]) by fmviesa002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Nov 2023 01:31:08 -0800 Received: by box.shutemov.name (Postfix, from userid 1000) id 14A2410A36E; Tue, 21 Nov 2023 12:31:05 +0300 (+03) Date: Tue, 21 Nov 2023 12:31:05 +0300 From: "kirill.shutemov@linux.intel.com" To: "Huang, Kai" Cc: "tglx@linutronix.de" , "mingo@redhat.com" , "x86@kernel.org" , "bp@alien8.de" , "dave.hansen@linux.intel.com" , "Edgecombe, Rick P" , "Reshetova, Elena" , "Nakajima, Jun" , "rafael@kernel.org" , "peterz@infradead.org" , "linux-kernel@vger.kernel.org" , "sathyanarayanan.kuppuswamy@linux.intel.com" , "Hunter, Adrian" , "thomas.lendacky@amd.com" , "ashish.kalra@amd.com" , "kexec@lists.infradead.org" , "seanjc@google.com" , "bhe@redhat.com" , "linux-coco@lists.linux.dev" Subject: Re: [PATCHv3 03/14] cpu/hotplug: Add support for declaring CPU offlining not supported Message-ID: <20231121093105.ev77pgbssq6scugm@box.shutemov.name> References: <20231115120044.8034-1-kirill.shutemov@linux.intel.com> <20231115120044.8034-4-kirill.shutemov@linux.intel.com> Precedence: bulk X-Mailing-List: linux-coco@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Tue, Nov 21, 2023 at 02:15:59AM +0000, Huang, Kai wrote: > On Wed, 2023-11-15 at 15:00 +0300, Kirill A. Shutemov wrote: > > The ACPI MADT mailbox wakeup method doesn't allow to offline CPU after > > it got woke up. > > > > Currently offlining hotplug is prevented based on the confidential > > computing attribute which is set for Intel TDX. But TDX is not > > the only possible user of the wake up method. The MADT wakeup can be > > implemented outside of a confidential computing environment. Offline > > support is a property of the wakeup method, not the CoCo implementation. > > > > Introduce cpu_hotplug_not_supported() that can be called to indicate > > that CPU offlining should be disabled. > > cpu_hotplug_not_supported() -> cpu_hotplug_disable_offlining(). Right. > > > > This function is going to replace CC_ATTR_HOTPLUG_DISABLED for ACPI > > MADT. > > Is MADT too generic? MADT wakeup? I'll replace it with "ACPI MADT wakeup method". -- Kiryl Shutsemau / Kirill A. Shutemov