3 files changed, 20 insertions, 19 deletions

diff --git a/arch/x86/kernel/smp.c b/arch/x86/kernel/smp.c
index 8f75893a6467..0cb7aadc87cd 100644
--- a/arch/x86/kernel/smp.c
+++ b/arch/x86/kernel/smp.c
@@ -231,7 +231,8 @@ native_smp_call_function_mask(cpumask_t mask,
         wmb();
 
         /* Send a message to other CPUs */
-        if (cpus_equal(mask, allbutself))
+        if (cpus_equal(mask, allbutself) &&
+            cpus_equal(cpu_online_map, cpu_callout_map))
                 send_IPI_allbutself(CALL_FUNCTION_VECTOR);
         else
                 send_IPI_mask(mask, CALL_FUNCTION_VECTOR);
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index 6b087ab6cd8f..38988491c622 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -86,6 +86,7 @@ void *x86_bios_cpu_apicid_early_ptr;
 
 #ifdef CONFIG_X86_32
 u8 apicid_2_node[MAX_APICID];
+static int low_mappings;
 #endif
 
 /* State of each CPU */
@@ -326,6 +327,12 @@ static void __cpuinit start_secondary(void *unused)
                 enable_8259A_irq(0);
         }
 
+#ifdef CONFIG_X86_32
+        while (low_mappings)
+                cpu_relax();
+        __flush_tlb_all();
+#endif
+
         /* This must be done before setting cpu_online_map */
         set_cpu_sibling_map(raw_smp_processor_id());
         wmb();
@@ -1040,14 +1047,20 @@ int __cpuinit native_cpu_up(unsigned int cpu)
 #ifdef CONFIG_X86_32
         /* init low mem mapping */
         clone_pgd_range(swapper_pg_dir, swapper_pg_dir + KERNEL_PGD_BOUNDARY,
-                        min_t(unsigned long, KERNEL_PGD_PTRS, KERNEL_PGD_BOUNDARY));
+                min_t(unsigned long, KERNEL_PGD_PTRS, KERNEL_PGD_BOUNDARY));
         flush_tlb_all();
-#endif
+        low_mappings = 1;
 
         err = do_boot_cpu(apicid, cpu);
-        if (err < 0) {
+
+        zap_low_mappings();
+        low_mappings = 0;
+#else
+        err = do_boot_cpu(apicid, cpu);
+#endif
+        if (err) {
                 Dprintk("do_boot_cpu failed %d\n", err);
-                return err;
+                return -EIO;
         }
 
         /*
@@ -1259,9 +1272,6 @@ void __init native_smp_cpus_done(unsigned int max_cpus)
         setup_ioapic_dest();
 #endif
         check_nmi_watchdog();
-#ifdef CONFIG_X86_32
-        zap_low_mappings();
-#endif
 }
 
 #ifdef CONFIG_HOTPLUG_CPU
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index de236e419cb5..ec30d10154b6 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -438,8 +438,6 @@ void zap_low_mappings(void)
 {
         int i;
 
-        save_pg_dir();
-
         /*
          * Zap initial low-memory mappings.
          *
@@ -663,16 +661,8 @@ void __init mem_init(void)
                 test_wp_bit();
 
         cpa_init();
-
-        /*
-         * Subtle. SMP is doing it's boot stuff late (because it has to
-         * fork idle threads) - but it also needs low mappings for the
-         * protected-mode entry to work. We zap these entries only after
-         * the WP-bit has been tested.
-         */
-#ifndef CONFIG_SMP
+        save_pg_dir();
         zap_low_mappings();
-#endif
 }
 
 #ifdef CONFIG_MEMORY_HOTPLUG