powerpc/pseries/dlpar: handle ibm, configure-connector delay status

dlpar_configure_connector() has two problems in its handling of
ibm,configure-connector's return status:

1. When the status is -2 (busy, call again), we call
   ibm,configure-connector again immediately without checking whether
   to schedule, which can result in monopolizing the CPU.
2. Extended delay status (9900..9905) goes completely unhandled,
   causing the configuration to unnecessarily terminate.

Fix both of these issues by using rtas_busy_delay().

Fixes: ab519a011caa ("powerpc/pseries: Kernel DLPAR Infrastructure")
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Tyrel Datwyler <tyreld@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210107025900.410369-1-nathanl@linux.ibm.com

diff --git a/arch/powerpc/platforms/pseries/dlpar.c b/arch/powerpc/platforms/pseries/dlpar.c
index deb48b41d488fa713c66c35730226ad0f9f372e4..233503fcf8f08fb1747633b8f4f41907dab9025b 100644 (file)
--- a/arch/powerpc/platforms/pseries/dlpar.c
+++ b/arch/powerpc/platforms/pseries/dlpar.c
@@ -127,7 +127,6 @@ void dlpar_free_cc_nodes(struct device_node *dn)
 #define NEXT_PROPERTY   3
 #define PREV_PARENT     4
 #define MORE_MEMORY     5
-#define CALL_AGAIN     -2
 #define ERR_CFG_USE     -9003
 
 struct device_node *dlpar_configure_connector(__be32 drc_index,
@@ -168,6 +167,9 @@ struct device_node *dlpar_configure_connector(__be32 drc_index,
 
                spin_unlock(&rtas_data_buf_lock);
 
+               if (rtas_busy_delay(rc))
+                       continue;
+
                switch (rc) {
                case COMPLETE:
                        break;
@@ -216,9 +218,6 @@ struct device_node *dlpar_configure_connector(__be32 drc_index,
                        last_dn = last_dn->parent;
                        break;
 
-               case CALL_AGAIN:
-                       break;
-
                case MORE_MEMORY:
                case ERR_CFG_USE:
                default: