x86: check vmlinux limits, 64-bit

[linux-2.6] / arch / x86 / kernel / head64.c

diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c
index 8561f626edad129ca13d2d4603cac32a6ed30b96..38f32e798a99913ff2b1995159e771559e990164 100644 (file)
--- a/arch/x86/kernel/head64.c
+++ b/arch/x86/kernel/head64.c
@@ -10,22 +10,24 @@
 #include <linux/kernel.h>
 #include <linux/string.h>
 #include <linux/percpu.h>
+#include <linux/start_kernel.h>
 
 #include <asm/processor.h>
 #include <asm/proto.h>
 #include <asm/smp.h>
-#include <asm/bootsetup.h>
 #include <asm/setup.h>
 #include <asm/desc.h>
 #include <asm/pgtable.h>
 #include <asm/tlbflush.h>
 #include <asm/sections.h>
+#include <asm/kdebug.h>
+#include <asm/e820.h>
 
 static void __init zap_identity_mappings(void)
 {
        pgd_t *pgd = pgd_offset_k(0UL);
        pgd_clear(pgd);
-       __flush_tlb();
+       __flush_tlb_all();
 }
 
 /* Don't add a printk in there. printk relies on the PDA which is not initialized 
@@ -36,41 +38,80 @@ static void __init clear_bss(void)
               (unsigned long) __bss_stop - (unsigned long) __bss_start);
 }
 
-#define NEW_CL_POINTER         0x228   /* Relative to real mode data */
-#define OLD_CL_MAGIC_ADDR      0x20
-#define OLD_CL_MAGIC            0xA33F
-#define OLD_CL_OFFSET           0x22
-
 static void __init copy_bootdata(char *real_mode_data)
 {
-       unsigned long new_data;
        char * command_line;
 
-       memcpy(x86_boot_params, real_mode_data, BOOT_PARAM_SIZE);
-       new_data = *(u32 *) (x86_boot_params + NEW_CL_POINTER);
-       if (!new_data) {
-               if (OLD_CL_MAGIC != *(u16 *)(real_mode_data + OLD_CL_MAGIC_ADDR)) {
-                       return;
-               }
-               new_data = __pa(real_mode_data) + *(u16 *)(real_mode_data + OLD_CL_OFFSET);
+       memcpy(&boot_params, real_mode_data, sizeof boot_params);
+       if (boot_params.hdr.cmd_line_ptr) {
+               command_line = __va(boot_params.hdr.cmd_line_ptr);
+               memcpy(boot_command_line, command_line, COMMAND_LINE_SIZE);
        }
-       command_line = __va(new_data);
-       memcpy(boot_command_line, command_line, COMMAND_LINE_SIZE);
+}
+
+#define EBDA_ADDR_POINTER 0x40E
+
+static __init void reserve_ebda(void)
+{
+       unsigned ebda_addr, ebda_size;
+
+       /*
+        * there is a real-mode segmented pointer pointing to the
+        * 4K EBDA area at 0x40E
+        */
+       ebda_addr = *(unsigned short *)__va(EBDA_ADDR_POINTER);
+       ebda_addr <<= 4;
+
+       if (!ebda_addr)
+               return;
+
+       ebda_size = *(unsigned short *)__va(ebda_addr);
+
+       /* Round EBDA up to pages */
+       if (ebda_size == 0)
+               ebda_size = 1;
+       ebda_size <<= 10;
+       ebda_size = round_up(ebda_size + (ebda_addr & ~PAGE_MASK), PAGE_SIZE);
+       if (ebda_size > 64*1024)
+               ebda_size = 64*1024;
+
+       reserve_early(ebda_addr, ebda_addr + ebda_size, "EBDA");
 }
 
 void __init x86_64_start_kernel(char * real_mode_data)
 {
        int i;
 
+       /*
+        * Build-time sanity checks on the kernel image and module
+        * area mappings. (these are purely build-time and produce no code)
+        */
+       BUILD_BUG_ON(MODULES_VADDR < KERNEL_IMAGE_START);
+       BUILD_BUG_ON(MODULES_VADDR-KERNEL_IMAGE_START < KERNEL_IMAGE_SIZE);
+       BUILD_BUG_ON(MODULES_LEN + KERNEL_IMAGE_SIZE > 2*PUD_SIZE);
+       BUILD_BUG_ON((KERNEL_IMAGE_START & ~PMD_MASK) != 0);
+       BUILD_BUG_ON((MODULES_VADDR & ~PMD_MASK) != 0);
+       BUILD_BUG_ON(!(MODULES_VADDR > __START_KERNEL));
+       BUILD_BUG_ON(!(((MODULES_END - 1) & PGDIR_MASK) ==
+                               (__START_KERNEL & PGDIR_MASK)));
+
        /* clear bss before set_intr_gate with early_idt_handler */
        clear_bss();
 
        /* Make NULL pointers segfault */
        zap_identity_mappings();
 
-       for (i = 0; i < IDT_ENTRIES; i++)
+       /* Cleanup the over mapped high alias */
+       cleanup_highmap();
+
+       for (i = 0; i < IDT_ENTRIES; i++) {
+#ifdef CONFIG_EARLY_PRINTK
+               set_intr_gate(i, &early_idt_handlers[i]);
+#else
                set_intr_gate(i, early_idt_handler);
-       asm volatile("lidt %0" :: "m" (idt_descr));
+#endif
+       }
+       load_idt((const struct desc_ptr *)&idt_descr);
 
        early_printk("Kernel alive\n");
 
@@ -79,8 +120,24 @@ void __init x86_64_start_kernel(char * real_mode_data)
 
        pda_init(0);
        copy_bootdata(__va(real_mode_data));
-#ifdef CONFIG_SMP
-       cpu_set(0, cpu_online_map);
-#endif
+
+       reserve_early(__pa_symbol(&_text), __pa_symbol(&_end), "TEXT DATA BSS");
+
+       /* Reserve INITRD */
+       if (boot_params.hdr.type_of_loader && boot_params.hdr.ramdisk_image) {
+               unsigned long ramdisk_image = boot_params.hdr.ramdisk_image;
+               unsigned long ramdisk_size  = boot_params.hdr.ramdisk_size;
+               unsigned long ramdisk_end   = ramdisk_image + ramdisk_size;
+               reserve_early(ramdisk_image, ramdisk_end, "RAMDISK");
+       }
+
+       reserve_ebda();
+
+       /*
+        * At this point everything still needed from the boot loader
+        * or BIOS or kernel text should be early reserved or marked not
+        * RAM in e820. All other memory is free game.
+        */
+
        start_kernel();
 }