1 files changed, 23 insertions, 6 deletions

diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 9452a54d356c..a7671786764b 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1185,6 +1185,9 @@ static inline void save_sprs(struct thread_struct *t)
 
 	if (cpu_has_feature(CPU_FTR_DEXCR_NPHIE))
 		t->hashkeyr = mfspr(SPRN_HASHKEYR);
+
+	if (cpu_has_feature(CPU_FTR_ARCH_31))
+		t->dexcr = mfspr(SPRN_DEXCR);
 #endif
 }
 
@@ -1267,6 +1270,10 @@ static inline void restore_sprs(struct thread_struct *old_thread,
 	if (cpu_has_feature(CPU_FTR_DEXCR_NPHIE) &&
 	    old_thread->hashkeyr != new_thread->hashkeyr)
 		mtspr(SPRN_HASHKEYR, new_thread->hashkeyr);
+
+	if (cpu_has_feature(CPU_FTR_ARCH_31) &&
+	    old_thread->dexcr != new_thread->dexcr)
+		mtspr(SPRN_DEXCR, new_thread->dexcr);
 #endif
 
 }
@@ -1634,6 +1641,13 @@ void arch_setup_new_exec(void)
 	current->thread.regs->amr  = default_amr;
 	current->thread.regs->iamr  = default_iamr;
 #endif
+
+#ifdef CONFIG_PPC_BOOK3S_64
+	if (cpu_has_feature(CPU_FTR_ARCH_31)) {
+		current->thread.dexcr = current->thread.dexcr_onexec;
+		mtspr(SPRN_DEXCR, current->thread.dexcr);
+	}
+#endif /* CONFIG_PPC_BOOK3S_64 */
 }
 
 #ifdef CONFIG_PPC64
@@ -1647,7 +1661,7 @@ void arch_setup_new_exec(void)
  * cases will happen:
  *
  * 1. The correct thread is running, the wrong thread is not
- * In this situation, the correct thread is woken and proceeds to pass it's
+ * In this situation, the correct thread is woken and proceeds to pass its
  * condition check.
  *
  * 2. Neither threads are running
@@ -1657,15 +1671,15 @@ void arch_setup_new_exec(void)
  * for the wrong thread, or they will execute the condition check immediately.
  *
  * 3. The wrong thread is running, the correct thread is not
- * The wrong thread will be woken, but will fail it's condition check and
+ * The wrong thread will be woken, but will fail its condition check and
  * re-execute wait. The correct thread, when scheduled, will execute either
- * it's condition check (which will pass), or wait, which returns immediately
- * when called the first time after the thread is scheduled, followed by it's
+ * its condition check (which will pass), or wait, which returns immediately
+ * when called the first time after the thread is scheduled, followed by its
  * condition check (which will pass).
  *
  * 4. Both threads are running
- * Both threads will be woken. The wrong thread will fail it's condition check
- * and execute another wait, while the correct thread will pass it's condition
+ * Both threads will be woken. The wrong thread will fail its condition check
+ * and execute another wait, while the correct thread will pass its condition
  * check.
  *
  * @t: the task to set the thread ID for
@@ -1878,6 +1892,9 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args)
 #ifdef CONFIG_PPC_BOOK3S_64
 	if (cpu_has_feature(CPU_FTR_DEXCR_NPHIE))
 		p->thread.hashkeyr = current->thread.hashkeyr;
+
+	if (cpu_has_feature(CPU_FTR_ARCH_31))
+		p->thread.dexcr = mfspr(SPRN_DEXCR);
 #endif
 	return 0;
 }