Patch "ACPI / SRAT: fix SRAT parsing order with both LAPIC and X2APIC present" has been added to the 4.4-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    ACPI / SRAT: fix SRAT parsing order with both LAPIC and X2APIC present

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     acpi-srat-fix-srat-parsing-order-with-both-lapic-and-x2apic-present.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 702b07fcc9b264c9afd372676bbdd50a762dcde0 Mon Sep 17 00:00:00 2001
From: Lukasz Anaczkowski <lukasz.anaczkowski@intel.com>
Date: Thu, 21 Apr 2016 11:29:00 +0200
Subject: ACPI / SRAT: fix SRAT parsing order with both LAPIC and X2APIC present

From: Lukasz Anaczkowski <lukasz.anaczkowski@intel.com>

commit 702b07fcc9b264c9afd372676bbdd50a762dcde0 upstream.

SRAT maps APIC ID to proximity domains ids (PXM). Mapping from PXM to
NUMA node ids is based on order of entries in SRAT table.
SRAT table has just LAPIC entires or mix of LAPIC and X2APIC entries.
As long as there are only LAPIC entires, mapping from proximity domain
id to NUMA node id is as assumed by BIOS. However, once APIC entries are
mixed, X2APIC entries would be first mapped which causes unexpected NUMA
node mapping.

To fix that, change parsing to check each entry against both LAPIC and
X2APIC so mapping is in the SRAT/PXM order.

This is supplemental change to the fix made by commit d81056b5278
(Handle apic/x2apic entries in MADT in correct order) and using the
mechanism introduced by 9b3fedd (ACPI / tables: Add acpi_subtable_proc
to ACPI table parsers).

Fixes: d81056b5278 (Handle apic/x2apic entries in MADT in correct order)
Signed-off-by: Lukasz Anaczkowski <lukasz.anaczkowski@intel.com>
[ rjw : Subject & changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/acpi/numa.c |   16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

--- a/drivers/acpi/numa.c
+++ b/drivers/acpi/numa.c
@@ -327,10 +327,18 @@ int __init acpi_numa_init(void)
 
 	/* SRAT: Static Resource Affinity Table */
 	if (!acpi_table_parse(ACPI_SIG_SRAT, acpi_parse_srat)) {
-		acpi_table_parse_srat(ACPI_SRAT_TYPE_X2APIC_CPU_AFFINITY,
-				     acpi_parse_x2apic_affinity, 0);
-		acpi_table_parse_srat(ACPI_SRAT_TYPE_CPU_AFFINITY,
-				     acpi_parse_processor_affinity, 0);
+		struct acpi_subtable_proc srat_proc[2];
+
+		memset(srat_proc, 0, sizeof(srat_proc));
+		srat_proc[0].id = ACPI_SRAT_TYPE_CPU_AFFINITY;
+		srat_proc[0].handler = acpi_parse_processor_affinity;
+		srat_proc[1].id = ACPI_SRAT_TYPE_X2APIC_CPU_AFFINITY;
+		srat_proc[1].handler = acpi_parse_x2apic_affinity;
+
+		acpi_table_parse_entries_array(ACPI_SIG_SRAT,
+					sizeof(struct acpi_table_srat),
+					srat_proc, ARRAY_SIZE(srat_proc), 0);
+
 		cnt = acpi_table_parse_srat(ACPI_SRAT_TYPE_MEMORY_AFFINITY,
 					    acpi_parse_memory_affinity,
 					    NR_NODE_MEMBLKS);


Patches currently in stable-queue which might be from lukasz.anaczkowski@intel.com are

queue-4.4/acpi-srat-fix-srat-parsing-order-with-both-lapic-and-x2apic-present.patch