[net-next-2.6.git] / arch / i386 / kernel / doublefault.c

#include <linux/mm.h>
#include <linux/sched.h>
#include <linux/init.h>
#include <linux/init_task.h>
#include <linux/fs.h>

#include <asm/uaccess.h>
#include <asm/pgtable.h>
#include <asm/processor.h>
#include <asm/desc.h>

#define DOUBLEFAULT_STACKSIZE (1024)
static unsigned long doublefault_stack[DOUBLEFAULT_STACKSIZE];
#define STACK_START (unsigned long)(doublefault_stack+DOUBLEFAULT_STACKSIZE)

#define ptr_ok(x) ((x) > PAGE_OFFSET && (x) < PAGE_OFFSET + 0x1000000)

static void doublefault_fn(void)
{
	struct Xgt_desc_struct gdt_desc = {0, 0};
	unsigned long gdt, tss;

	store_gdt(&gdt_desc);
	gdt = gdt_desc.address;

	printk("double fault, gdt at %08lx [%d bytes]\n", gdt, gdt_desc.size);

	if (ptr_ok(gdt)) {
		gdt += GDT_ENTRY_TSS << 3;
		tss = *(u16 *)(gdt+2);
		tss += *(u8 *)(gdt+4) << 16;
		tss += *(u8 *)(gdt+7) << 24;
		printk("double fault, tss at %08lx\n", tss);

		if (ptr_ok(tss)) {
			struct tss_struct *t = (struct tss_struct *)tss;

			printk("eip = %08lx, esp = %08lx\n", t->eip, t->esp);

			printk("eax = %08lx, ebx = %08lx, ecx = %08lx, edx = %08lx\n",
				t->eax, t->ebx, t->ecx, t->edx);
			printk("esi = %08lx, edi = %08lx\n",
				t->esi, t->edi);
		}
	}

	for (;;) /* nothing */;
}

struct tss_struct doublefault_tss __cacheline_aligned = {
	.esp0		= STACK_START,
	.ss0		= __KERNEL_DS,
	.ldt		= 0,
	.io_bitmap_base	= INVALID_IO_BITMAP_OFFSET,

	.eip		= (unsigned long) doublefault_fn,
	.eflags		= X86_EFLAGS_SF | 0x2,	/* 0x2 bit is always set */
	.esp		= STACK_START,
	.es		= __USER_DS,
	.cs		= __KERNEL_CS,
	.ss		= __KERNEL_DS,
	.ds		= __USER_DS,

	.__cr3		= __pa(swapper_pg_dir)
};
Commit	Line	Data
1da177e4 LT	1	#include <linux/mm.h>
	2	#include <linux/sched.h>
	3	#include <linux/init.h>
	4	#include <linux/init_task.h>
	5	#include <linux/fs.h>
	6
	7	#include <asm/uaccess.h>
	8	#include <asm/pgtable.h>
	9	#include <asm/processor.h>
	10	#include <asm/desc.h>
	11
	12	#define DOUBLEFAULT_STACKSIZE (1024)
	13	static unsigned long doublefault_stack[DOUBLEFAULT_STACKSIZE];
	14	#define STACK_START (unsigned long)(doublefault_stack+DOUBLEFAULT_STACKSIZE)
	15
	16	#define ptr_ok(x) ((x) > PAGE_OFFSET && (x) < PAGE_OFFSET + 0x1000000)
	17
	18	static void doublefault_fn(void)
	19	{
	20	struct Xgt_desc_struct gdt_desc = {0, 0};
	21	unsigned long gdt, tss;
	22
4d37e7e3	23	store_gdt(&gdt_desc);
1da177e4 LT	24	gdt = gdt_desc.address;
	25
	26	printk("double fault, gdt at %08lx [%d bytes]\n", gdt, gdt_desc.size);
	27
	28	if (ptr_ok(gdt)) {
	29	gdt += GDT_ENTRY_TSS << 3;
	30	tss = (u16 )(gdt+2);
	31	tss += (u8 )(gdt+4) << 16;
	32	tss += (u8 )(gdt+7) << 24;
	33	printk("double fault, tss at %08lx\n", tss);
	34
	35	if (ptr_ok(tss)) {
	36	struct tss_struct t = (struct tss_struct )tss;
	37
	38	printk("eip = %08lx, esp = %08lx\n", t->eip, t->esp);
	39
	40	printk("eax = %08lx, ebx = %08lx, ecx = %08lx, edx = %08lx\n",
	41	t->eax, t->ebx, t->ecx, t->edx);
	42	printk("esi = %08lx, edi = %08lx\n",
	43	t->esi, t->edi);
	44	}
	45	}
	46
	47	for (;;) /* nothing */;
	48	}
	49
	50	struct tss_struct doublefault_tss __cacheline_aligned = {
	51	.esp0 = STACK_START,
	52	.ss0 = __KERNEL_DS,
	53	.ldt = 0,
	54	.io_bitmap_base = INVALID_IO_BITMAP_OFFSET,
	55
	56	.eip = (unsigned long) doublefault_fn,
	57	.eflags = X86_EFLAGS_SF \| 0x2, /* 0x2 bit is always set */
	58	.esp = STACK_START,
	59	.es = __USER_DS,
	60	.cs = __KERNEL_CS,
	61	.ss = __KERNEL_DS,
	62	.ds = __USER_DS,
	63
	64	.__cr3 = __pa(swapper_pg_dir)
	65	};