[PATCH] mm, x86: Skip NUMA_NO_NODE while parsing SLIT

[Toshi Kani <toshi.kani@hp.com>]

When ACPI SLIT table has an I/O locality (i.e. a locality unique
to an I/O device), numa_set_distance() emits the warning message
below.

 NUMA: Warning: node ids are out of bound, from=-1 to=-1 distance=10

acpi_numa_slit_init() calls numa_set_distance() with pxm_to_node(),
which assumes that all localities have been parsed with SRAT previously.
SRAT does not list I/O localities, where as SLIT lists all localities
including I/Os.  Hence, pxm_to_node() returns NUMA_NO_NODE (-1) for
an I/O locality.  I/O localities are not supported and are ignored
today, but emitting such warning message leads unnecessary confusion.

Change acpi_numa_slit_init() to avoid calling numa_set_distance()
with NUMA_NO_NODE.

Signed-off-by: Toshi Kani <toshi.kani@hp.com>
---
 arch/x86/mm/srat.c |   10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/arch/x86/mm/srat.c b/arch/x86/mm/srat.c
index 266ca91..29a2ced 100644
--- a/arch/x86/mm/srat.c
+++ b/arch/x86/mm/srat.c
@@ -47,10 +47,16 @@ void __init acpi_numa_slit_init(struct acpi_table_slit *slit)
 {
 	int i, j;
 
-	for (i = 0; i < slit->locality_count; i++)
-		for (j = 0; j < slit->locality_count; j++)
+	for (i = 0; i < slit->locality_count; i++) {
+		if (pxm_to_node(i) == NUMA_NO_NODE)
+			continue;
+		for (j = 0; j < slit->locality_count; j++) {
+			if (pxm_to_node(j) == NUMA_NO_NODE)
+				continue;
 			numa_set_distance(pxm_to_node(i), pxm_to_node(j),
 				slit->entry[slit->locality_count * i + j]);
+		}
+	}
 }
 
 /* Callback for Proximity Domain -> x2APIC mapping */

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