diff options
Diffstat (limited to 'arch/x86_64/kernel/head64.c')
| -rw-r--r-- | arch/x86_64/kernel/head64.c | 34 |
1 files changed, 19 insertions, 15 deletions
diff --git a/arch/x86_64/kernel/head64.c b/arch/x86_64/kernel/head64.c index 5f197b0a330a..6c34bdd22e26 100644 --- a/arch/x86_64/kernel/head64.c +++ b/arch/x86_64/kernel/head64.c @@ -18,8 +18,16 @@ #include <asm/setup.h> #include <asm/desc.h> #include <asm/pgtable.h> +#include <asm/tlbflush.h> #include <asm/sections.h> +static void __init zap_identity_mappings(void) +{ + pgd_t *pgd = pgd_offset_k(0UL); + pgd_clear(pgd); + __flush_tlb(); +} + /* Don't add a printk in there. printk relies on the PDA which is not initialized yet. */ static void __init clear_bss(void) @@ -29,25 +37,24 @@ static void __init clear_bss(void) } #define NEW_CL_POINTER 0x228 /* Relative to real mode data */ -#define OLD_CL_MAGIC_ADDR 0x90020 +#define OLD_CL_MAGIC_ADDR 0x20 #define OLD_CL_MAGIC 0xA33F -#define OLD_CL_BASE_ADDR 0x90000 -#define OLD_CL_OFFSET 0x90022 +#define OLD_CL_OFFSET 0x22 static void __init copy_bootdata(char *real_mode_data) { - int new_data; + unsigned long new_data; char * command_line; memcpy(x86_boot_params, real_mode_data, BOOT_PARAM_SIZE); - new_data = *(int *) (x86_boot_params + NEW_CL_POINTER); + new_data = *(u32 *) (x86_boot_params + NEW_CL_POINTER); if (!new_data) { - if (OLD_CL_MAGIC != * (u16 *) OLD_CL_MAGIC_ADDR) { + if (OLD_CL_MAGIC != *(u16 *)(real_mode_data + OLD_CL_MAGIC_ADDR)) { return; } - new_data = OLD_CL_BASE_ADDR + * (u16 *) OLD_CL_OFFSET; + new_data = __pa(real_mode_data) + *(u16 *)(real_mode_data + OLD_CL_OFFSET); } - command_line = (char *) ((u64)(new_data)); + command_line = __va(new_data); memcpy(boot_command_line, command_line, COMMAND_LINE_SIZE); } @@ -58,23 +65,20 @@ void __init x86_64_start_kernel(char * real_mode_data) /* 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++) set_intr_gate(i, early_idt_handler); asm volatile("lidt %0" :: "m" (idt_descr)); early_printk("Kernel alive\n"); - /* - * switch to init_level4_pgt from boot_level4_pgt - */ - memcpy(init_level4_pgt, boot_level4_pgt, PTRS_PER_PGD*sizeof(pgd_t)); - asm volatile("movq %0,%%cr3" :: "r" (__pa_symbol(&init_level4_pgt))); - for (i = 0; i < NR_CPUS; i++) cpu_pda(i) = &boot_cpu_pda[i]; pda_init(0); - copy_bootdata(real_mode_data); + copy_bootdata(__va(real_mode_data)); #ifdef CONFIG_SMP cpu_set(0, cpu_online_map); #endif |
