blackfin: smp: fix msg queue overflow issue

disable preemption when icache flush and use wait mode cross call, hold the msg
queue lock while handle cross function call to avoid overflow

Signed-off-by: Steven Miao <realmz6@gmail.com>
Signed-off-by: Bob Liu <lliubbo@gmail.com>

diff --git a/arch/blackfin/mach-common/smp.c b/arch/blackfin/mach-common/smp.c
index d3464053dfdbad287317fd280d9b09af3ece61ea..ac8f8a43158c5b85b5524d15bd3a74b8d5de0507 100644 (file)
--- a/arch/blackfin/mach-common/smp.c
+++ b/arch/blackfin/mach-common/smp.c
@@ -193,14 +193,10 @@ static irqreturn_t ipi_handler_int1(int irq, void *dev_instance)
                        scheduler_ipi();
                        break;
                case BFIN_IPI_CALL_FUNC:
-                       spin_unlock_irqrestore(&msg_queue->lock, flags);
                        ipi_call_function(cpu, msg);
-                       spin_lock_irqsave(&msg_queue->lock, flags);
                        break;
                case BFIN_IPI_CPU_STOP:
-                       spin_unlock_irqrestore(&msg_queue->lock, flags);
                        ipi_cpu_stop(cpu);
-                       spin_lock_irqsave(&msg_queue->lock, flags);
                        break;
                default:
                        printk(KERN_CRIT "CPU%u: Unknown IPI message 0x%lx\n",
@@ -482,8 +478,10 @@ void smp_icache_flush_range_others(unsigned long start, unsigned long end)
        smp_flush_data.start = start;
        smp_flush_data.end = end;
 
-       if (smp_call_function(&ipi_flush_icache, &smp_flush_data, 0))
+       preempt_disable();
+       if (smp_call_function(&ipi_flush_icache, &smp_flush_data, 1))
                printk(KERN_WARNING "SMP: failed to run I-cache flush request on other CPUs\n");
+       preempt_enable();
 }
 EXPORT_SYMBOL_GPL(smp_icache_flush_range_others);