1 files changed, 9 insertions, 3 deletions

diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index bfdd783e3916..5acb5a176dbe 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1569,16 +1569,22 @@ void arch_release_task_struct(struct task_struct *t)
  */
 int set_thread_tidr(struct task_struct *t)
 {
+        int rc;
+
         if (!cpu_has_feature(CPU_FTR_ARCH_300))
                 return -EINVAL;
 
         if (t != current)
                 return -EINVAL;
 
-        t->thread.tidr = assign_thread_tidr();
-        if (t->thread.tidr < 0)
-                return t->thread.tidr;
+        if (t->thread.tidr)
+                return 0;
+
+        rc = assign_thread_tidr();
+        if (rc < 0)
+                return rc;
 
+        t->thread.tidr = rc;
         mtspr(SPRN_TIDR, t->thread.tidr);
 
         return 0;