Commit 99759869faf1 "acpi: Add acpi_map_pxm_to_online_node()" added support for mapping a given proximity to its nearest, by SLIT distance, online node. However, it sometimes returns unexpected results due to the fact that it switches from comparing the PXM node to the last node that was closer than the current max.
for_each_online_node(n) { dist = node_distance(node, n); if (dist < min_dist) { min_dist = dist; node = n; <---- from this point we're using the wrong node for node_distance()
Fixes: 99759869faf1 ("acpi: Add acpi_map_pxm_to_online_node()") Cc: stable@vger.kernel.org Cc: Toshi Kani toshi.kani@hp.com Cc: Rafael J. Wysocki rafael.j.wysocki@intel.com> Signed-off-by: Dan Williams dan.j.williams@intel.com --- Rafael, I can take this through the nvdimm tree with your ack. I have a few other nvdimm fixes pending for 4.16.
drivers/acpi/numa.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/drivers/acpi/numa.c b/drivers/acpi/numa.c index 8ccaae3550d2..85167603b9c9 100644 --- a/drivers/acpi/numa.c +++ b/drivers/acpi/numa.c @@ -103,25 +103,27 @@ int acpi_map_pxm_to_node(int pxm) */ int acpi_map_pxm_to_online_node(int pxm) { - int node, n, dist, min_dist; + int node, min_node;
node = acpi_map_pxm_to_node(pxm);
if (node == NUMA_NO_NODE) node = 0;
+ min_node = node; if (!node_online(node)) { - min_dist = INT_MAX; + int min_dist = INT_MAX, dist, n; + for_each_online_node(n) { dist = node_distance(node, n); if (dist < min_dist) { min_dist = dist; - node = n; + min_node = n; } } }
- return node; + return min_node; } EXPORT_SYMBOL(acpi_map_pxm_to_online_node);