[PATCH 3.19.y-ckt 38/92] powerpc/pseries: Correct cpu affinity for dlpar added cpus

[Kamal Mostafa]

3.19.8-ckt1 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Nathan Fontenot <nfont at linux.vnet.ibm.com>

commit f32393c943e297b8ae180c8f83d81a156c7d0412 upstream.

The incorrect ordering of operations during cpu dlpar add results in invalid
affinity for the cpu being added. The ibm,associativity property in the
device tree is populated with all zeroes for the added cpu which results in
invalid affinity mappings and all cpus appear to belong to node 0.

This occurs because rtas configure-connector is called prior to making the
rtas set-indicator calls. Phyp does not assign affinity information
for a cpu until the rtas set-indicator calls are made to set the isolation
and allocation state.

Correct the order of operations to make the rtas set-indicator
calls (done in dlpar_acquire_drc) before calling rtas configure-connector.

Fixes: 1a8061c46c46 ("powerpc/pseries: Add kernel based CPU DLPAR handling")

Signed-off-by: Nathan Fontenot <nfont at linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe at ellerman.id.au>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 arch/powerpc/platforms/pseries/dlpar.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/arch/powerpc/platforms/pseries/dlpar.c b/arch/powerpc/platforms/pseries/dlpar.c
index c22bb1b..0991578 100644
--- a/arch/powerpc/platforms/pseries/dlpar.c
+++ b/arch/powerpc/platforms/pseries/dlpar.c
@@ -410,6 +410,10 @@ static ssize_t dlpar_cpu_probe(const char *buf, size_t count)
 	if (rc)
 		return -EINVAL;
 
+	rc = dlpar_acquire_drc(drc_index);
+	if (rc)
+		return -EINVAL;
+
 	parent = of_find_node_by_path("/cpus");
 	if (!parent)
 		return -ENODEV;
@@ -420,12 +424,6 @@ static ssize_t dlpar_cpu_probe(const char *buf, size_t count)
 
 	of_node_put(parent);
 
-	rc = dlpar_acquire_drc(drc_index);
-	if (rc) {
-		dlpar_free_cc_nodes(dn);
-		return -EINVAL;
-	}
-
 	rc = dlpar_attach_node(dn);
 	if (rc) {
 		dlpar_release_drc(drc_index);
-- 
1.9.1