x86: Use get_desc_base() (254e0a6b) · Commits · 戴 / test

arch/x86/kernel/doublefault_32.c

+1 −3

Original line number	Diff line number	Diff line
		@@ -27,9 +27,7 @@ static void doublefault_fn(void)

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

		if (ptr_ok(tss)) {

+4 −5

Original line number	Diff line number	Diff line
		@@ -4,6 +4,7 @@
		#include <linux/sched.h>
		#include <linux/mm.h>
		#include <linux/ptrace.h>
		#include <asm/desc.h>

		unsigned long convert_ip_to_linear(struct task_struct child, struct pt_regs regs)
		{
		@@ -23,7 +24,7 @@ unsigned long convert_ip_to_linear(struct task_struct child, struct pt_regs re
		* and APM bios ones we just ignore here.
		*/
		if ((seg & SEGMENT_TI_MASK) == SEGMENT_LDT) {
		u32 *desc;
		struct desc_struct *desc;
		unsigned long base;

		seg &= ~7UL;
		@@ -33,12 +34,10 @@ unsigned long convert_ip_to_linear(struct task_struct child, struct pt_regs re
		addr = -1L; /* bogus selector, access would fault */
		else {
		desc = child->mm->context.ldt + seg;
		base = ((desc[0] >> 16) \|
		((desc[1] & 0xff) << 16) \|
		(desc[1] & 0xff000000));
		base = get_desc_base(desc);

		/* 16-bit code segment? */
		if (!((desc[1] >> 22) & 1))
		if (!desc->d)
		addr &= 0xffff;
		addr += base;
		}