From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CE9AAC76196 for ; Tue, 28 Mar 2023 05:53:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232126AbjC1Fxk (ORCPT ); Tue, 28 Mar 2023 01:53:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41312 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229452AbjC1Fxi (ORCPT ); Tue, 28 Mar 2023 01:53:38 -0400 Received: from mga06.intel.com (mga06b.intel.com [134.134.136.31]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 456151BFE for ; Mon, 27 Mar 2023 22:53:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1679982818; x=1711518818; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=FF+DUqCGHy8oPyFBqiYg8s10DunJo6T+TgdcwHN7O5g=; b=ESv2E2dNjMHASUtegF+EayvwPAK6RCh8Soc3l07IZvHlYJm5mDlJD45g DvpqBqTHk+wuAzcn5YthmLIxbIqcOjE4ItYnxcjP32hiZWrCFY07x0TJq 1OeSdNkdN2lCcw3Ob8HbEVWCGmZA4+aZ7zwveGWDt78lmjgkXtl6LGtyX SdeXQt48wPG2DlHU71isKS2rDDTgMF5m2/ehPZth+KG1gyEkxGM9BIMmq BSkQ6I5p2N+axBu48UcN/hY5MmpK5mDRoWnWvKr+8n7UyLeMdhoIHiwJd ytU+dkGSedaTOaN9WgbEn8bq92R3psFqHZrFMwgGYE9cEIukaSCDvPza0 w==; X-IronPort-AV: E=McAfee;i="6600,9927,10662"; a="403088288" X-IronPort-AV: E=Sophos;i="5.98,296,1673942400"; d="scan'208";a="403088288" Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Mar 2023 22:53:37 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10662"; a="752987372" X-IronPort-AV: E=Sophos;i="5.98,296,1673942400"; d="scan'208";a="752987372" Received: from skunchit-mobl.amr.corp.intel.com (HELO [10.209.35.30]) ([10.209.35.30]) by fmsmga004-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Mar 2023 22:53:36 -0700 Message-ID: Date: Sat, 25 Mar 2023 09:20:47 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.7.1 Subject: Re: [PATCH] x86: Disable kexec for TDX guests Content-Language: en-US To: "Kirill A. Shutemov" , Dave Hansen , Borislav Petkov Cc: Thomas Gleixner , Ingo Molnar , x86@kernel.org, Eric Biederman , kexec@lists.infradead.org, linux-kernel@vger.kernel.org References: <20230325160128.21857-1-kirill.shutemov@linux.intel.com> From: Dave Hansen In-Reply-To: <20230325160128.21857-1-kirill.shutemov@linux.intel.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 3F461C76196 for ; Tue, 28 Mar 2023 05:53:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:From:References:Cc:To: Subject:MIME-Version:Date:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=QVkzbv7pLzedSZKY4hqZKGO+W4BnqUngq1BgHdPGFcE=; b=XkhVWjrge+xgN5 ojdSHn+gAAhUOLIQWoxWvM2NwtH67hgW5Ib98fP9meUZ4ps+Vq9OFqbkFsyCvinDlXiJM9n47rgjB PKtMbxsxHxrlmcoQkYUD9ZSVV8C4dAvl4tk/wkxEQ4kOeMHvIZYKAH8K5HEB5dP311vF5jpQZ/KCV Hwk67D2nUz0a7ZEUgXSCFek1+vymvQnHRQMYqRqogAsmWEXre+MOuEmDK3Aio/3E27t1eDycUHWu0 sYBoeU/pLiuNvJE6NG+hwo8zfqyUqZby5FLlHiyh6ZGqV+8uMAXoILpqmspwgpOBmqPJ3gB4ByGmz 7BiJQl27rH3yQ0JVbfbg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1ph2H6-00DEKu-2A; Tue, 28 Mar 2023 05:53:40 +0000 Received: from mga06b.intel.com ([134.134.136.31] helo=mga06.intel.com) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1ph2H4-00DEKM-2c for kexec@lists.infradead.org; Tue, 28 Mar 2023 05:53:39 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1679982818; x=1711518818; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=FF+DUqCGHy8oPyFBqiYg8s10DunJo6T+TgdcwHN7O5g=; b=ESv2E2dNjMHASUtegF+EayvwPAK6RCh8Soc3l07IZvHlYJm5mDlJD45g DvpqBqTHk+wuAzcn5YthmLIxbIqcOjE4ItYnxcjP32hiZWrCFY07x0TJq 1OeSdNkdN2lCcw3Ob8HbEVWCGmZA4+aZ7zwveGWDt78lmjgkXtl6LGtyX SdeXQt48wPG2DlHU71isKS2rDDTgMF5m2/ehPZth+KG1gyEkxGM9BIMmq BSkQ6I5p2N+axBu48UcN/hY5MmpK5mDRoWnWvKr+8n7UyLeMdhoIHiwJd ytU+dkGSedaTOaN9WgbEn8bq92R3psFqHZrFMwgGYE9cEIukaSCDvPza0 w==; X-IronPort-AV: E=McAfee;i="6600,9927,10662"; a="403088284" X-IronPort-AV: E=Sophos;i="5.98,296,1673942400"; d="scan'208";a="403088284" Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Mar 2023 22:53:37 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10662"; a="752987372" X-IronPort-AV: E=Sophos;i="5.98,296,1673942400"; d="scan'208";a="752987372" Received: from skunchit-mobl.amr.corp.intel.com (HELO [10.209.35.30]) ([10.209.35.30]) by fmsmga004-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Mar 2023 22:53:36 -0700 Message-ID: Date: Sat, 25 Mar 2023 09:20:47 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.7.1 Subject: Re: [PATCH] x86: Disable kexec for TDX guests Content-Language: en-US To: "Kirill A. Shutemov" , Dave Hansen , Borislav Petkov Cc: Thomas Gleixner , Ingo Molnar , x86@kernel.org, Eric Biederman , kexec@lists.infradead.org, linux-kernel@vger.kernel.org References: <20230325160128.21857-1-kirill.shutemov@linux.intel.com> From: Dave Hansen In-Reply-To: <20230325160128.21857-1-kirill.shutemov@linux.intel.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230327_225338_907859_456DB595 X-CRM114-Status: UNSURE ( 8.98 ) X-CRM114-Notice: Please train this message. X-BeenThere: kexec@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kexec" Errors-To: kexec-bounces+kexec=archiver.kernel.org@lists.infradead.org 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 _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec