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>

3 files changed, 34 insertions, 33 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;
 }
 
diff --git a/drivers/acpi/numa.c b/drivers/acpi/numa.c
index 5d59cb33b1a5..658e5f3abae0 100644
--- a/drivers/acpi/numa.c
+++ b/drivers/acpi/numa.c
@@ -140,19 +140,42 @@ acpi_table_print_srat_entry(struct acpi_subtable_header *header)
         }
 }
 
+/*
+ * 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;
+}
+
 static int __init acpi_parse_slit(struct acpi_table_header *table)
 {
         struct acpi_table_slit *slit;
-        u32 localities;
 
         if (!table)
                 return -EINVAL;
 
         slit = (struct acpi_table_slit *)table;
 
-        /* downcast just for %llu vs %lu for i386/ia64  */
-        localities = (u32) slit->locality_count;
-
+        if (!slit_valid(slit)) {
+                printk(KERN_INFO "ACPI: SLIT table looks invalid. Not used.\n");
+                return -EINVAL;
+        }
         acpi_numa_slit_init(slit);
 
         return 0;