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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id F2AA5C05027 for ; Tue, 14 Feb 2023 16:02:02 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 8C98C6B0081; Tue, 14 Feb 2023 11:02:02 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 879216B0082; Tue, 14 Feb 2023 11:02:02 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7419A6B0083; Tue, 14 Feb 2023 11:02:02 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id 614346B0081 for ; Tue, 14 Feb 2023 11:02:02 -0500 (EST) Received: from smtpin23.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 26EF5120881 for ; Tue, 14 Feb 2023 16:02:02 +0000 (UTC) X-FDA: 80466363684.23.5BBD4D7 Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) by imf28.hostedemail.com (Postfix) with ESMTP id 77803C0047 for ; Tue, 14 Feb 2023 16:01:57 +0000 (UTC) Authentication-Results: imf28.hostedemail.com; dkim=pass header.d=infradead.org header.s=desiato.20200630 header.b=ZDwawV4f; dmarc=none; spf=none (imf28.hostedemail.com: domain of peterz@infradead.org has no SPF policy when checking 90.155.92.199) smtp.mailfrom=peterz@infradead.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1676390517; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=B8m1WYTfCwIRBef7Ts4H70l01shy+i4ZZD4VBDlUF0g=; b=hZ2u7RN6oYMDo9YgJFbHiGuWxArjDv/TDXsw/4A5KrdDXNLCciAnZe6JDQ4eXbkss9GxV6 VgC0WMJYqNhc30+h859Sa+FfltodT5d+LGdQ7bpqhUoLzPdx74qRWZ8zX3sYuY6FAibLd6 Mc1T7J+ZuO/cysUgmv9jReAn4j6/Uvg= ARC-Authentication-Results: i=1; imf28.hostedemail.com; dkim=pass header.d=infradead.org header.s=desiato.20200630 header.b=ZDwawV4f; dmarc=none; spf=none (imf28.hostedemail.com: domain of peterz@infradead.org has no SPF policy when checking 90.155.92.199) smtp.mailfrom=peterz@infradead.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1676390517; a=rsa-sha256; cv=none; b=r/9nxSBx7nFDWv1n5WWE238VGHlztvAQvhTh51q2wK3S7ZW8bFCF6+ivtPsPya0SIJaUNR DKJsrzMCabf+FYNUnCWjEdB0Ic0AZYSf0oRAoQi0pN9cjbTn4ZxgZZMfPdcyrsIHp9LBjL MiTVd52Q8qpN2ECr/rGtONDZsMLCWO8= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=B8m1WYTfCwIRBef7Ts4H70l01shy+i4ZZD4VBDlUF0g=; b=ZDwawV4fqwWJVQzsvQDK+7YUXU gUppfAqBUVHj+lMaQ2ZlUmxKBjn+YdN437IPZGReHldG5w5ImBOKSusm9jzKCKEiH0MtHZiAokwk4 yQd6BBjnFQNZh6lebR18Pmpqvk1NXjDOrfYzSpXgq4CTULk92CcdofvENu+YV62J0NuHooZZb0++G F7wLAGKhXqpAsOFbQT7HI/Z5dHq3xtPWRH5LYuEtqly1qqtOJlgXNHuzqOtsmBYZVBUL+3BlA34dC xgSvSnKZD2dia7cqDJ8G2JRLm7j+Cm5c2P/Bvdvj63JURLRFbBLxRKdxq8xnI6xHZrqpYaekxlOWX +0/wcc/Q==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.96 #2 (Red Hat Linux)) id 1pRxju-009g7r-31; Tue, 14 Feb 2023 16:01:49 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id B9CDF3033FF; Tue, 14 Feb 2023 15:12:50 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id AC39F23BDBD82; Tue, 14 Feb 2023 15:12:50 +0100 (CET) Date: Tue, 14 Feb 2023 15:12:50 +0100 From: Peter Zijlstra To: Dave Hansen Cc: Kai Huang , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, linux-mm@kvack.org, tglx@linutronix.de, seanjc@google.com, pbonzini@redhat.com, dan.j.williams@intel.com, rafael.j.wysocki@intel.com, kirill.shutemov@linux.intel.com, ying.huang@intel.com, reinette.chatre@intel.com, len.brown@intel.com, tony.luck@intel.com, ak@linux.intel.com, isaku.yamahata@intel.com, chao.gao@intel.com, sathyanarayanan.kuppuswamy@linux.intel.com, david@redhat.com, bagasdotme@gmail.com, sagis@google.com, imammedo@redhat.com Subject: Re: [PATCH v9 07/18] x86/virt/tdx: Do TDX module per-cpu initialization Message-ID: References: <557c526a1190903d11d67c4e2c76e01f67f6eb15.1676286526.git.kai.huang@intel.com> <2d9172c5-e1e7-bf94-c52b-0e9bc5b5b319@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <2d9172c5-e1e7-bf94-c52b-0e9bc5b5b319@intel.com> X-Rspamd-Queue-Id: 77803C0047 X-Rspamd-Server: rspam09 X-Rspam-User: X-Stat-Signature: 9mji6pncp5ypbi7g9jz4qmpqeajrughu X-HE-Tag: 1676390517-781327 X-HE-Meta: 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 RyBa7lkW GQYJdyDNqppvve8yLpW0o5aVNG3HFwHvDUb/+Mc/x3CzGvmQfKYZE/LGSc/evDr0Yh0c3MBpfHnD4OQog4RhHADhwrcjF1cworgPv6OlWO5TzYy9m85rIqs1C1CgaS8eD97zYb1QBnv4p6iJ0aIb3GhfctsPuaCH/YUei X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, Feb 13, 2023 at 10:07:30AM -0800, Dave Hansen wrote: > On 2/13/23 03:59, Kai Huang wrote: > > @@ -247,8 +395,17 @@ int tdx_enable(void) > > ret = __tdx_enable(); > > break; > > case TDX_MODULE_INITIALIZED: > > - /* Already initialized, great, tell the caller. */ > > - ret = 0; > > + /* > > + * The previous call of __tdx_enable() may only have > > + * initialized part of present cpus during module > > + * initialization, and new cpus may have become online > > + * since then. > > + * > > + * To make sure all online cpus are TDX-runnable, always > > + * do per-cpu initialization for all online cpus here > > + * even the module has been initialized. > > + */ > > + ret = __tdx_enable_online_cpus(); > > I'm missing something here. CPUs get initialized through either: > > 1. __tdx_enable(), for the CPUs around at the time > 2. tdx_cpu_online(), for hotplugged CPUs after __tdx_enable() > > But, this is a third class. CPUs that came online after #1, but which > got missed by #2. How can that happen? offline CPUs, start TDX crap, online CPUs.