1 files changed, 35 insertions, 13 deletions

diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 0b93893424f5..a8cca88e972f 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -139,12 +139,16 @@ EXPORT_SYMBOL(__msr_check_and_clear);
 #ifdef CONFIG_PPC_FPU
 void __giveup_fpu(struct task_struct *tsk)
 {
+        unsigned long msr;
+
         save_fpu(tsk);
-        tsk->thread.regs->msr &= ~MSR_FP;
+        msr = tsk->thread.regs->msr;
+        msr &= ~MSR_FP;
 #ifdef CONFIG_VSX
         if (cpu_has_feature(CPU_FTR_VSX))
-                tsk->thread.regs->msr &= ~MSR_VSX;
+                msr &= ~MSR_VSX;
 #endif
+        tsk->thread.regs->msr = msr;
 }
 
 void giveup_fpu(struct task_struct *tsk)
@@ -219,12 +223,16 @@ static int restore_fp(struct task_struct *tsk) { return 0; }
 
 static void __giveup_altivec(struct task_struct *tsk)
 {
+        unsigned long msr;
+
         save_altivec(tsk);
-        tsk->thread.regs->msr &= ~MSR_VEC;
+        msr = tsk->thread.regs->msr;
+        msr &= ~MSR_VEC;
 #ifdef CONFIG_VSX
         if (cpu_has_feature(CPU_FTR_VSX))
-                tsk->thread.regs->msr &= ~MSR_VSX;
+                msr &= ~MSR_VSX;
 #endif
+        tsk->thread.regs->msr = msr;
 }
 
 void giveup_altivec(struct task_struct *tsk)
@@ -794,7 +802,7 @@ static void tm_reclaim_thread(struct thread_struct *thr,
          * this state.
          * We do this using the current MSR, rather tracking it in
          * some specific thread_struct bit, as it has the additional
-         * benifit of checking for a potential TM bad thing exception.
+         * benefit of checking for a potential TM bad thing exception.
          */
         if (!MSR_TM_SUSPENDED(mfmsr()))
                 return;
@@ -1009,6 +1017,14 @@ static inline void save_sprs(struct thread_struct *t)
                  */
                 t->tar = mfspr(SPRN_TAR);
         }
+
+        if (cpu_has_feature(CPU_FTR_ARCH_300)) {
+                /* Conditionally save Load Monitor registers, if enabled */
+                if (t->fscr & FSCR_LM) {
+                        t->lmrr = mfspr(SPRN_LMRR);
+                        t->lmser = mfspr(SPRN_LMSER);
+                }
+        }
 #endif
 }
 
@@ -1023,18 +1039,11 @@ static inline void restore_sprs(struct thread_struct *old_thread,
 #ifdef CONFIG_PPC_BOOK3S_64
         if (cpu_has_feature(CPU_FTR_DSCR)) {
                 u64 dscr = get_paca()->dscr_default;
-                u64 fscr = old_thread->fscr & ~FSCR_DSCR;
-
-                if (new_thread->dscr_inherit) {
+                if (new_thread->dscr_inherit)
                         dscr = new_thread->dscr;
-                        fscr |= FSCR_DSCR;
-                }
 
                 if (old_thread->dscr != dscr)
                         mtspr(SPRN_DSCR, dscr);
-
-                if (old_thread->fscr != fscr)
-                        mtspr(SPRN_FSCR, fscr);
         }
 
         if (cpu_has_feature(CPU_FTR_ARCH_207S)) {
@@ -1045,9 +1054,22 @@ static inline void restore_sprs(struct thread_struct *old_thread,
                 if (old_thread->ebbrr != new_thread->ebbrr)
                         mtspr(SPRN_EBBRR, new_thread->ebbrr);
 
+                if (old_thread->fscr != new_thread->fscr)
+                        mtspr(SPRN_FSCR, new_thread->fscr);
+
                 if (old_thread->tar != new_thread->tar)
                         mtspr(SPRN_TAR, new_thread->tar);
         }
+
+        if (cpu_has_feature(CPU_FTR_ARCH_300)) {
+                /* Conditionally restore Load Monitor registers, if enabled */
+                if (new_thread->fscr & FSCR_LM) {
+                        if (old_thread->lmrr != new_thread->lmrr)
+                                mtspr(SPRN_LMRR, new_thread->lmrr);
+                        if (old_thread->lmser != new_thread->lmser)
+                                mtspr(SPRN_LMSER, new_thread->lmser);
+                }
+        }
 #endif
 }