ACPI: handle invalid ACPI SLIT table

This is a SLIT sanity checking patch.  It moves slit_valid() function to
generic ACPI code and does sanity checking for both x86 and ia64.  It sets up
node_distance with LOCAL_DISTANCE and REMOTE_DISTANCE when hitting invalid
SLIT table on ia64.  It also cleans up unused variable localities in
acpi_parse_slit() on x86.

Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>

2 files changed, 7 insertions, 29 deletions

diff --git a/arch/ia64/kernel/acpi.c b/arch/ia64/kernel/acpi.c
index 853d1f11be00..43687cc60dfb 100644
--- a/arch/ia64/kernel/acpi.c
+++ b/arch/ia64/kernel/acpi.c
@@ -465,7 +465,6 @@ void __init acpi_numa_slit_init(struct acpi_table_slit *slit)
 		printk(KERN_ERR
 		       "ACPI 2.0 SLIT: size mismatch: %d expected, %d actual\n",
 		       len, slit->header.length);
-		memset(numa_slit, 10, sizeof(numa_slit));
 		return;
 	}
 	slit_table = slit;
@@ -574,8 +573,14 @@ void __init acpi_numa_arch_fixup(void)
 	printk(KERN_INFO "Number of memory chunks in system = %d\n",
 	       num_node_memblks);
 
-	if (!slit_table)
+	if (!slit_table) {
+		for (i = 0; i < MAX_NUMNODES; i++)
+			for (j = 0; j < MAX_NUMNODES; j++)
+				node_distance(i, j) = i == j ? LOCAL_DISTANCE :
+							REMOTE_DISTANCE;
 		return;
+	}
+
 	memset(numa_slit, -1, sizeof(numa_slit));
 	for (i = 0; i < slit_table->locality_count; i++) {
 		if (!pxm_bit_test(i))
diff --git a/arch/x86/mm/srat_64.c b/arch/x86/mm/srat_64.c
index 3890234e5b26..99649dccad28 100644
--- a/arch/x86/mm/srat_64.c
+++ b/arch/x86/mm/srat_64.c
@@ -97,36 +97,9 @@ static __init inline int srat_disabled(void)
 	return numa_off || acpi_numa < 0;
 }
 
-/*
- * A lot of BIOS fill in 10 (= no distance) everywhere. This messes
- * up the NUMA heuristics which wants the local node to have a smaller
- * distance than the others.
- * Do some quick checks here and only use the SLIT if it passes.
- */
-static __init int slit_valid(struct acpi_table_slit *slit)
-{
-	int i, j;
-	int d = slit->locality_count;
-	for (i = 0; i < d; i++) {
-		for (j = 0; j < d; j++)  {
-			u8 val = slit->entry[d*i + j];
-			if (i == j) {
-				if (val != LOCAL_DISTANCE)
-					return 0;
-			} else if (val <= LOCAL_DISTANCE)
-				return 0;
-		}
-	}
-	return 1;
-}
-
 /* Callback for SLIT parsing */
 void __init acpi_numa_slit_init(struct acpi_table_slit *slit)
 {
-	if (!slit_valid(slit)) {
-		printk(KERN_INFO "ACPI: SLIT table looks invalid. Not used.\n");
-		return;
-	}
 	acpi_slit = slit;
 }