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 3A5F0C77B73 for ; Fri, 19 May 2023 00:26:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229512AbjESA0Y (ORCPT ); Thu, 18 May 2023 20:26:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32874 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230430AbjESA0W (ORCPT ); Thu, 18 May 2023 20:26:22 -0400 Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 785C2E0; Thu, 18 May 2023 17:26:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1684455966; x=1715991966; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=vmNO3nCpeED9i66p4eJ06n2xbLKfA9JoMG33j6lzFIg=; b=ELtDRQUHOdwmsyI4NPGmLdOtkzoN9/DMcbhqhWSb2T2JxlT9ab3OdghU spKQgbgrhtMkAxmrPPwV5xw7jGylHq5U5XoZ99ltpauEQANeXxCld8rHF t/dVgzG0UFUF4a8aNqKnmsLKXymjOhmzVtHtem4fANXu1eSnCDmN9Jios zprSy6cdA3NLpasiaEVea0VpFBuX91r7iHOsTA/Ar2x5Ux7+fVnW15Jhn +nobccGqaEpSPUPA4x9pCPWwmSq1IEpZirVPVcPdzn89QEZlnI2xe2MbK wEyBpXjIt324TxEwu/0xJJNJuzHeADetSFtLRQO+dCpKwbKlJUsBpt9LH A==; X-IronPort-AV: E=McAfee;i="6600,9927,10714"; a="355451069" X-IronPort-AV: E=Sophos;i="6.00,175,1681196400"; d="scan'208";a="355451069" Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 May 2023 17:26:05 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10714"; a="705376838" X-IronPort-AV: E=Sophos;i="6.00,175,1681196400"; d="scan'208";a="705376838" Received: from aschofie-mobl2.amr.corp.intel.com (HELO aschofie-mobl2) ([10.251.20.44]) by fmsmga007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 May 2023 17:26:04 -0700 Date: Thu, 18 May 2023 17:26:03 -0700 From: Alison Schofield To: Dave Hansen Cc: "Rafael J. Wysocki" , Len Brown , Dan Williams , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , Andy Lutomirski , Peter Zijlstra , Andrew Morton , Jonathan Cameron , Dave Jiang , x86@kernel.org, linux-cxl@vger.kernel.org, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/2] x86/numa: Introduce numa_fill_memblks() Message-ID: References: <8dc725c8-613a-b51b-6cc1-80d2275ca130@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <8dc725c8-613a-b51b-6cc1-80d2275ca130@intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-cxl@vger.kernel.org On Thu, May 18, 2023 at 05:08:16PM -0700, Dave Hansen wrote: > On 5/18/23 17:04, alison.schofield@intel.com wrote: > > The initial use case is the ACPI driver that needs to extend > > SRAT defined proximity domains to an entire CXL CFMWS Window[1]. > > Dumb question time: Why didn't the SRAT just cover this sucker in the > first place? Are we fixing up a BIOS bug or is there a legitimate > reason that the SRAT didn't cover it up front? > > There is no requirement that the BIOS describe (in the SRAT) all the HPA assigned to a CFMWS Window. The HPA range may not actually map to any memory at boot time. It can be persistent capacity or may be there to enable hot-plug. IIUC BIOS can pick and choose and define volatile regions wherever it pleases. So, no we're not fixing up a BIOS bug, nor doing a BIOS sanity check.