From: Fengguang Wu <fengguang.wu@intel.com>
Subject: [RFC][PATCH v2 01/21] e820: cheat PMEM as DRAM
Date: Wed, 26 Dec 2018 21:14:47 +0800
Message-ID: <20181226133351.106676005@intel.com>
References: <20181226131446.330864849@intel.com>
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Cc: Linux Memory Management List <linux-mm@kvack.org>,
        Fan Du <fan.du@intel.com>,
        Fengguang Wu <fengguang.wu@intel.com>
To: Andrew Morton <akpm@linux-foundation.org>
Return-path: <linux-kernel-owner@vger.kernel.org>
cc: kvm@vger.kernel.org
Cc: LKML <linux-kernel@vger.kernel.org>
cc: Yao Yuan <yuan.yao@intel.com>
cc: Peng Dong <dongx.peng@intel.com>
cc: Huang Ying <ying.huang@intel.com>
CC: Liu Jingqi <jingqi.liu@intel.com>
cc: Dong Eddie <eddie.dong@intel.com>
cc: Dave Hansen <dave.hansen@intel.com>
cc: Zhang Yi <yi.z.zhang@linux.intel.com>
cc: Dan Williams <dan.j.williams@intel.com>
Content-Disposition: inline; filename=0001-e820-Force-PMEM-entry-as-RAM-type-to-enumerate-NUMA-.patch
Sender: linux-kernel-owner@vger.kernel.org
List-Id: kvm.vger.kernel.org

From: Fan Du <fan.du@intel.com>

This is a hack to enumerate PMEM as NUMA nodes.
It's necessary for current BIOS that don't yet fill ACPI HMAT table.

WARNING: take care to backup. It is mutual exclusive with libnvdimm
subsystem and can destroy ndctl managed namespaces.

Signed-off-by: Fan Du <fan.du@intel.com>
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
---
 arch/x86/kernel/e820.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- linux.orig/arch/x86/kernel/e820.c	2018-12-23 19:20:34.587078783 +0800
+++ linux/arch/x86/kernel/e820.c	2018-12-23 19:20:34.587078783 +0800
@@ -403,7 +403,8 @@ static int __init __append_e820_table(st
 		/* Ignore the entry on 64-bit overflow: */
 		if (start > end && likely(size))
 			return -1;
-
+		if (type == E820_TYPE_PMEM)
+			type = E820_TYPE_RAM;
 		e820__range_add(start, size, type);
 
 		entry++;