1 files changed, 31 insertions, 31 deletions

diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index f8a7a1a1a9f4..ef2074c3e906 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -588,23 +588,19 @@ _GLOBAL(ret_from_except_lite)
 fast_exc_return_irq:
 restore:
         /*
-         * This is the main kernel exit path, we first check if we
-         * have to change our interrupt state.
+         * This is the main kernel exit path. First we check if we
+         * are about to re-enable interrupts
          */
         ld      r5,SOFTE(r1)
         lbz     r6,PACASOFTIRQEN(r13)
-        cmpwi   cr1,r5,0
-        cmpw    cr0,r5,r6
-        beq     cr0,4f
+        cmpwi   cr0,r5,0
+        beq     restore_irq_off
 
-        /* We do, handle disable first, which is easy */
-        bne     cr1,3f;
-        li      r0,0
-        stb     r0,PACASOFTIRQEN(r13);
-        TRACE_DISABLE_INTS
-        b       4f
+        /* We are enabling, were we already enabled ? Yes, just return */
+        cmpwi   cr0,r6,1
+        beq     cr0,do_restore
 
-3:      /*
+        /*
          * We are about to soft-enable interrupts (we are hard disabled
          * at this point). We check if there's anything that needs to
          * be replayed first.
@@ -626,7 +622,7 @@ restore_no_replay:
         /*
          * Final return path. BookE is handled in a different file
          */
-4:
+do_restore:
 #ifdef CONFIG_PPC_BOOK3E
         b       .exception_return_book3e
 #else
@@ -700,6 +696,25 @@ fast_exception_return:
 #endif /* CONFIG_PPC_BOOK3E */
 
         /*
+         * We are returning to a context with interrupts soft disabled.
+         *
+         * However, we may also about to hard enable, so we need to
+         * make sure that in this case, we also clear PACA_IRQ_HARD_DIS
+         * or that bit can get out of sync and bad things will happen
+         */
+restore_irq_off:
+        ld      r3,_MSR(r1)
+        lbz     r7,PACAIRQHAPPENED(r13)
+        andi.   r0,r3,MSR_EE
+        beq     1f
+        rlwinm  r7,r7,0,~PACA_IRQ_HARD_DIS
+        stb     r7,PACAIRQHAPPENED(r13)
+1:      li      r0,0
+        stb     r0,PACASOFTIRQEN(r13);
+        TRACE_DISABLE_INTS
+        b       do_restore
+
+        /*
          * Something did happen, check if a re-emit is needed
          * (this also clears paca->irq_happened)
          */
@@ -748,6 +763,9 @@ restore_check_irq_replay:
 #endif /* CONFIG_PPC_BOOK3E */
 1:      b       .ret_from_except /* What else to do here ? */
  
+
+
+3:
 do_work:
 #ifdef CONFIG_PREEMPT
         andi.   r0,r3,MSR_PR    /* Returning to user mode? */
@@ -767,16 +785,6 @@ do_work:
         SOFT_DISABLE_INTS(r3,r4)
 1:      bl      .preempt_schedule_irq
 
-        /* Hard-disable interrupts again (and update PACA) */
-#ifdef CONFIG_PPC_BOOK3E
-        wrteei  0
-#else
-        ld      r10,PACAKMSR(r13) /* Get kernel MSR without EE */
-        mtmsrd  r10,1
-#endif /* CONFIG_PPC_BOOK3E */
-        li      r0,PACA_IRQ_HARD_DIS
-        stb     r0,PACAIRQHAPPENED(r13)
-
         /* Re-test flags and eventually loop */
         clrrdi  r9,r1,THREAD_SHIFT
         ld      r4,TI_FLAGS(r9)
@@ -787,14 +795,6 @@ do_work:
 user_work:
 #endif /* CONFIG_PREEMPT */
 
-        /* Enable interrupts */
-#ifdef CONFIG_PPC_BOOK3E
-        wrteei  1
-#else
-        ori     r10,r10,MSR_EE
-        mtmsrd  r10,1
-#endif /* CONFIG_PPC_BOOK3E */
-
         andi.   r0,r4,_TIF_NEED_RESCHED
         beq     1f
         bl      .restore_interrupts