6 files changed, 33 insertions, 5 deletions

diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index d22e73e4618b..e514de57a125 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -439,6 +439,8 @@ ret_from_fork:
 ret_from_kernel_thread:
         REST_NVGPRS(r1)
         bl      schedule_tail
+        li      r3,0
+        stw     r3,0(r1)
         mtlr    r14
         mr      r3,r15
         PPC440EP_ERR42
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index b310a0573625..3d990d3bd8ba 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -664,6 +664,19 @@ resume_kernel:
         ld      r4,TI_FLAGS(r9)
         andi.   r0,r4,_TIF_NEED_RESCHED
         bne     1b
+
+        /*
+         * arch_local_irq_restore() from preempt_schedule_irq above may
+         * enable hard interrupt but we really should disable interrupts
+         * when we return from the interrupt, and so that we don't get
+         * interrupted after loading SRR0/1.
+         */
+#ifdef CONFIG_PPC_BOOK3E
+        wrteei  0
+#else
+        ld      r10,PACAKMSR(r13) /* Get kernel MSR without EE */
+        mtmsrd  r10,1             /* Update machine state */
+#endif /* CONFIG_PPC_BOOK3E */
 #endif /* CONFIG_PREEMPT */
 
         .globl  fast_exc_return_irq
diff --git a/arch/powerpc/kernel/kgdb.c b/arch/powerpc/kernel/kgdb.c
index c470a40b29f5..a7bc7521c064 100644
--- a/arch/powerpc/kernel/kgdb.c
+++ b/arch/powerpc/kernel/kgdb.c
@@ -154,12 +154,12 @@ static int kgdb_handle_breakpoint(struct pt_regs *regs)
 static int kgdb_singlestep(struct pt_regs *regs)
 {
         struct thread_info *thread_info, *exception_thread_info;
-        struct thread_info *backup_current_thread_info = \
-                (struct thread_info *)kmalloc(sizeof(struct thread_info), GFP_KERNEL);
+        struct thread_info *backup_current_thread_info;
 
         if (user_mode(regs))
                 return 0;
 
+        backup_current_thread_info = (struct thread_info *)kmalloc(sizeof(struct thread_info), GFP_KERNEL);
         /*
          * On Book E and perhaps other processors, singlestep is handled on
          * the critical exception stack.  This causes current_thread_info()
@@ -185,6 +185,7 @@ static int kgdb_singlestep(struct pt_regs *regs)
                 /* Restore current_thread_info lastly. */
                 memcpy(exception_thread_info, backup_current_thread_info, sizeof *thread_info);
 
+        kfree(backup_current_thread_info);
         return 1;
 }
 
diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
index 6f6b1cccc916..127361e093f4 100644
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c
@@ -494,10 +494,15 @@ void timer_interrupt(struct pt_regs * regs)
         set_dec(DECREMENTER_MAX);
 
         /* Some implementations of hotplug will get timer interrupts while
-         * offline, just ignore these
+         * offline, just ignore these and we also need to set
+         * decrementers_next_tb as MAX to make sure __check_irq_replay
+         * don't replay timer interrupt when return, otherwise we'll trap
+         * here infinitely :(
          */
-        if (!cpu_online(smp_processor_id()))
+        if (!cpu_online(smp_processor_id())) {
+                *next_tb = ~(u64)0;
                 return;
+        }
 
         /* Conditionally hard-enable interrupts now that the DEC has been
          * bumped to its maximum value
diff --git a/arch/powerpc/oprofile/op_model_power4.c b/arch/powerpc/oprofile/op_model_power4.c
index 315f9495e9b2..f444b94935f5 100644
--- a/arch/powerpc/oprofile/op_model_power4.c
+++ b/arch/powerpc/oprofile/op_model_power4.c
@@ -52,7 +52,7 @@ static int power7_marked_instr_event(u64 mmcr1)
         for (pmc = 0; pmc < 4; pmc++) {
                 psel = mmcr1 & (OPROFILE_PM_PMCSEL_MSK
                                 << (OPROFILE_MAX_PMC_NUM - pmc)
-                                * OPROFILE_MAX_PMC_NUM);
+                                * OPROFILE_PMSEL_FIELD_WIDTH);
                 psel = (psel >> ((OPROFILE_MAX_PMC_NUM - pmc)
                                  * OPROFILE_PMSEL_FIELD_WIDTH)) & ~1ULL;
                 unit = mmcr1 & (OPROFILE_PM_UNIT_MSK
diff --git a/arch/powerpc/platforms/pasemi/cpufreq.c b/arch/powerpc/platforms/pasemi/cpufreq.c
index 95d00173029f..890f30e70f98 100644
--- a/arch/powerpc/platforms/pasemi/cpufreq.c
+++ b/arch/powerpc/platforms/pasemi/cpufreq.c
@@ -236,6 +236,13 @@ out:
 
 static int pas_cpufreq_cpu_exit(struct cpufreq_policy *policy)
 {
+        /*
+         * We don't support CPU hotplug. Don't unmap after the system
+         * has already made it to a running state.
+         */
+        if (system_state != SYSTEM_BOOTING)
+                return 0;
+
         if (sdcasr_mapbase)
                 iounmap(sdcasr_mapbase);
         if (sdcpwr_mapbase)