1 files changed, 11 insertions, 3 deletions

diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index 9ed796ccc32c..e63a5bd2a78f 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -1534,6 +1534,11 @@ void intel_ir_io_apic_print_entries(unsigned int apic,
         }
 }
 
+void ioapic_zap_locks(void)
+{
+        raw_spin_lock_init(&ioapic_lock);
+}
+
 __apicdebuginit(void) print_IO_APIC(int ioapic_idx)
 {
         union IO_APIC_reg_00 reg_00;
@@ -3375,12 +3380,15 @@ int io_apic_setup_irq_pin_once(unsigned int irq, int node,
 {
         unsigned int ioapic_idx = attr->ioapic, pin = attr->ioapic_pin;
         int ret;
+        struct IO_APIC_route_entry orig_entry;
 
         /* Avoid redundant programming */
         if (test_bit(pin, ioapics[ioapic_idx].pin_programmed)) {
-                pr_debug("Pin %d-%d already programmed\n",
-                         mpc_ioapic_id(ioapic_idx), pin);
-                return 0;
+                pr_debug("Pin %d-%d already programmed\n", mpc_ioapic_id(ioapic_idx), pin);
+                orig_entry = ioapic_read_entry(attr->ioapic, pin);
+                if (attr->trigger == orig_entry.trigger && attr->polarity == orig_entry.polarity)
+                        return 0;
+                return -EBUSY;
         }
         ret = io_apic_setup_irq_pin(irq, node, attr);
         if (!ret)