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authorIngo Molnar <mingo@elte.hu>2008-06-16 11:21:27 +0200
committerIngo Molnar <mingo@elte.hu>2008-06-16 11:21:27 +0200
commit688d22e23ab1caacb2c36c615854294b58f2ea47 (patch)
tree95c8163c0b1f56902f5537bc256d7e5507f56cee /drivers/acpi/numa.c
parent7e0edc1bc343231029084761ebf59e522902eb49 (diff)
parent066519068ad2fbe98c7f45552b1f592903a9c8c8 (diff)
Merge branch 'linus' into x86/xentip-x86-xen-2008-06-16_09.21_Mon
Diffstat (limited to 'drivers/acpi/numa.c')
-rw-r--r--drivers/acpi/numa.c31
1 files changed, 27 insertions, 4 deletions
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;