1 files changed, 35 insertions, 12 deletions

diff --git a/arch/x86/realmode/init.c b/arch/x86/realmode/init.c
index 705e3fffb4a1..5db706f14111 100644
--- a/arch/x86/realmode/init.c
+++ b/arch/x86/realmode/init.c
@@ -1,9 +1,11 @@
 #include <linux/io.h>
+#include <linux/slab.h>
 #include <linux/memblock.h>
 
 #include <asm/cacheflush.h>
 #include <asm/pgtable.h>
 #include <asm/realmode.h>
+#include <asm/tlbflush.h>
 
 struct real_mode_header *real_mode_header;
 u32 *trampoline_cr4_features;
@@ -11,25 +13,37 @@ u32 *trampoline_cr4_features;
 /* Hold the pgd entry used on booting additional CPUs */
 pgd_t trampoline_pgd_entry;
 
+void __init set_real_mode_mem(phys_addr_t mem, size_t size)
+{
+        void *base = __va(mem);
+
+        real_mode_header = (struct real_mode_header *) base;
+        printk(KERN_DEBUG "Base memory trampoline at [%p] %llx size %zu\n",
+               base, (unsigned long long)mem, size);
+}
+
 void __init reserve_real_mode(void)
 {
         phys_addr_t mem;
-        unsigned char *base;
-        size_t size = PAGE_ALIGN(real_mode_blob_end - real_mode_blob);
+        size_t size = real_mode_size_needed();
+
+        if (!size)
+                return;
+
+        WARN_ON(slab_is_available());
 
         /* Has to be under 1M so we can execute real-mode AP code. */
         mem = memblock_find_in_range(0, 1<<20, size, PAGE_SIZE);
-        if (!mem)
-                panic("Cannot allocate trampoline\n");
+        if (!mem) {
+                pr_info("No sub-1M memory is available for the trampoline\n");
+                return;
+        }
 
-        base = __va(mem);
         memblock_reserve(mem, size);
-        real_mode_header = (struct real_mode_header *) base;
-        printk(KERN_DEBUG "Base memory trampoline at [%p] %llx size %zu\n",
-               base, (unsigned long long)mem, size);
+        set_real_mode_mem(mem, size);
 }
 
-void __init setup_real_mode(void)
+static void __init setup_real_mode(void)
 {
         u16 real_mode_seg;
         const u32 *rel;
@@ -84,7 +98,7 @@ void __init setup_real_mode(void)
 
         trampoline_header->start = (u64) secondary_startup_64;
         trampoline_cr4_features = &trampoline_header->cr4;
-        *trampoline_cr4_features = __read_cr4();
+        *trampoline_cr4_features = mmu_cr4_features;
 
         trampoline_pgd = (u64 *) __va(real_mode_header->trampoline_pgd);
         trampoline_pgd[0] = trampoline_pgd_entry.pgd;
@@ -100,7 +114,7 @@ void __init setup_real_mode(void)
  * need to mark it executable at do_pre_smp_initcalls() at least,
  * thus run it as a early_initcall().
  */
-static int __init set_real_mode_permissions(void)
+static void __init set_real_mode_permissions(void)
 {
         unsigned char *base = (unsigned char *) real_mode_header;
         size_t size = PAGE_ALIGN(real_mode_blob_end - real_mode_blob);
@@ -119,7 +133,16 @@ static int __init set_real_mode_permissions(void)
         set_memory_nx((unsigned long) base, size >> PAGE_SHIFT);
         set_memory_ro((unsigned long) base, ro_size >> PAGE_SHIFT);
         set_memory_x((unsigned long) text_start, text_size >> PAGE_SHIFT);
+}
+
+static int __init init_real_mode(void)
+{
+        if (!real_mode_header)
+                panic("Real mode trampoline was not allocated");
+
+        setup_real_mode();
+        set_real_mode_permissions();
 
         return 0;
 }
-early_initcall(set_real_mode_permissions);
+early_initcall(init_real_mode);