1 files changed, 13 insertions, 19 deletions

diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index a5e928b0cb5f..abf4a86ffc54 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -73,7 +73,6 @@
 
 #ifdef CONFIG_X86_32
 u8 apicid_2_node[MAX_APICID];
-static int low_mappings;
 #endif
 
 /* State of each CPU */
@@ -281,6 +280,18 @@ notrace static void __cpuinit start_secondary(void *unused)
          * fragile that we want to limit the things done here to the
          * most necessary things.
          */
+
+#ifdef CONFIG_X86_32
+        /*
+         * Switch away from the trampoline page-table
+         *
+         * Do this before cpu_init() because it needs to access per-cpu
+         * data which may not be mapped in the trampoline page-table.
+         */
+        load_cr3(swapper_pg_dir);
+        __flush_tlb_all();
+#endif
+
         vmi_bringup();
         cpu_init();
         preempt_disable();
@@ -299,12 +310,6 @@ notrace static void __cpuinit start_secondary(void *unused)
                 legacy_pic->chip->unmask(0);
         }
 
-#ifdef CONFIG_X86_32
-        while (low_mappings)
-                cpu_relax();
-        __flush_tlb_all();
-#endif
-
         /* This must be done before setting cpu_online_mask */
         set_cpu_sibling_map(raw_smp_processor_id());
         wmb();
@@ -750,6 +755,7 @@ do_rest:
 #ifdef CONFIG_X86_32
         /* Stack for startup_32 can be just as for start_secondary onwards */
         irq_ctx_init(cpu);
+        initial_page_table = __pa(&trampoline_pg_dir);
 #else
         clear_tsk_thread_flag(c_idle.idle, TIF_FORK);
         initial_gs = per_cpu_offset(cpu);
@@ -897,20 +903,8 @@ int __cpuinit native_cpu_up(unsigned int cpu)
 
         per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
 
-#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));
-        flush_tlb_all();
-        low_mappings = 1;
-
         err = do_boot_cpu(apicid, cpu);
 
-        zap_low_mappings(false);
-        low_mappings = 0;
-#else
-        err = do_boot_cpu(apicid, cpu);
-#endif
         if (err) {
                 pr_debug("do_boot_cpu failed %d\n", err);
                 return -EIO;