From 5e47e7598d8e136803168f1e40e5d6ad29e3f155 Mon Sep 17 00:00:00 2001
From: Andi Kleen <ak@suse.de>
Date: Wed, 11 Jan 2006 22:44:39 +0100
Subject: [PATCH] --- yaml --- r: 17971 b: refs/heads/master c:
 8a6fdd3e912e0ce6f723431d66baf704bf8a1d26 h: refs/heads/master i:   17969:
 954e367a4a2bc8506cefcf5eda366dae254d7f34   17967:
 f8e8f2eea703d1c6df0ce55c589ee313d9c71f0d v: v3

---
 [refs]                      |  2 +-
 trunk/arch/x86_64/mm/srat.c | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 34 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index 670cb6b3dc73..114764a8dcce 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 95833c83f3b812c78e48db4eaa19f6c74958470b
+refs/heads/master: 8a6fdd3e912e0ce6f723431d66baf704bf8a1d26
diff --git a/trunk/arch/x86_64/mm/srat.c b/trunk/arch/x86_64/mm/srat.c
index d96c701dbed6..8b7f85608fa8 100644
--- a/trunk/arch/x86_64/mm/srat.c
+++ b/trunk/arch/x86_64/mm/srat.c
@@ -17,6 +17,7 @@
 #include <linux/topology.h>
 #include <asm/proto.h>
 #include <asm/numa.h>
+#include <asm/e820.h>
 
 static struct acpi_table_slit *acpi_slit;
 
@@ -196,12 +197,39 @@ acpi_numa_memory_affinity_init(struct acpi_table_memory_affinity *ma)
 	       nd->start, nd->end);
 }
 
+/* Sanity check to catch more bad SRATs (they are amazingly common).
+   Make sure the PXMs cover all memory. */
+static int nodes_cover_memory(void)
+{
+	int i;
+	unsigned long pxmram, e820ram;
+
+	pxmram = 0;
+	for_each_node_mask(i, nodes_parsed) {
+		unsigned long s = nodes[i].start >> PAGE_SHIFT;
+		unsigned long e = nodes[i].end >> PAGE_SHIFT;
+		pxmram += e - s;
+		pxmram -= e820_hole_size(s, e);
+	}
+
+	e820ram = end_pfn - e820_hole_size(0, end_pfn);
+	if (pxmram < e820ram) {
+		printk(KERN_ERR
+	"SRAT: PXMs only cover %luMB of your %luMB e820 RAM. Not used.\n",
+			(pxmram << PAGE_SHIFT) >> 20,
+			(e820ram << PAGE_SHIFT) >> 20);
+		return 0;
+	}
+	return 1;
+}
+
 void __init acpi_numa_arch_fixup(void) {}
 
 /* Use the information discovered above to actually set up the nodes. */
 int __init acpi_scan_nodes(unsigned long start, unsigned long end)
 {
 	int i;
+
 	if (acpi_numa <= 0)
 		return -1;
 
@@ -212,6 +240,11 @@ int __init acpi_scan_nodes(unsigned long start, unsigned long end)
 			node_clear(i, nodes_parsed);
 	}
 
+	if (!nodes_cover_memory()) {
+		bad_srat();
+		return -1;
+	}
+
 	memnode_shift = compute_hash_shift(nodes, nodes_weight(nodes_parsed));
 	if (memnode_shift < 0) {
 		printk(KERN_ERR