unsigned char *max_instr;
#ifdef CONFIG_X86_32
- unsigned long limit;
if (unlikely(boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
boot_cpu_data.x86 >= 6)) {
/* Catch an obscure case of prefetch inside an NX page. */
} else {
return 0;
}
- instr = (unsigned char *)get_segment_eip(regs, &limit);
#else
/* If it was a exec fault ignore */
if (error_code & PF_INSTR)
return 0;
- instr = (unsigned char __user *)convert_rip_to_linear(current, regs);
#endif
+ instr = (unsigned char *)convert_ip_to_linear(current, regs);
max_instr = instr + 15;
-#ifdef CONFIG_X86_64
if (user_mode(regs) && instr >= (unsigned char *)TASK_SIZE)
return 0;
-#endif
while (scan_more && instr < max_instr) {
unsigned char opcode;
unsigned char instr_hi;
unsigned char instr_lo;
-#ifdef CONFIG_X86_32
- if (instr > (unsigned char *)limit)
- break;
-#endif
if (probe_kernel_address(instr, opcode))
break;
case 0x00:
/* Prefetch instruction is 0x0F0D or 0x0F18 */
scan_more = 0;
-#ifdef CONFIG_X86_32
- if (instr > (unsigned char *)limit)
- break;
-#endif
+
if (probe_kernel_address(instr, opcode))
break;
prefetch = (instr_lo == 0xF) &&
KERN_ERR "******* Working around it, but it may cause SEGVs or burn power.\n"
KERN_ERR "******* Please consider a BIOS update.\n"
KERN_ERR "******* Disabling USB legacy in the BIOS may also help.\n";
+#endif
/* Workaround for K8 erratum #93 & buggy BIOS.
BIOS SMM functions are required to use a specific workaround
A lot of BIOS that didn't get tested properly miss this.
The OS sees this as a page fault with the upper 32bits of RIP cleared.
Try to work around it here.
- Note we only handle faults in kernel here. */
-
+ Note we only handle faults in kernel here.
+ Does nothing for X86_32
+ */
static int is_errata93(struct pt_regs *regs, unsigned long address)
{
+#ifdef CONFIG_X86_64
static int warned;
if (address != regs->ip)
return 0;
regs->ip = address;
return 1;
}
+#endif
return 0;
}
-#endif
static noinline void pgtable_bad(unsigned long address, struct pt_regs *regs,
unsigned long error_code)
*/
static int vmalloc_fault(unsigned long address)
{
+#ifdef CONFIG_X86_32
+ unsigned long pgd_paddr;
+ pmd_t *pmd_k;
+ pte_t *pte_k;
+ /*
+ * Synchronize this task's top level page-table
+ * with the 'reference' page table.
+ *
+ * Do _not_ use "current" here. We might be inside
+ * an interrupt in the middle of a task switch..
+ */
+ pgd_paddr = read_cr3();
+ pmd_k = vmalloc_sync_one(__va(pgd_paddr), address);
+ if (!pmd_k)
+ return -1;
+ pte_k = pte_offset_kernel(pmd_k, address);
+ if (!pte_present(*pte_k))
+ return -1;
+ return 0;
+#else
pgd_t *pgd, *pgd_ref;
pud_t *pud, *pud_ref;
pmd_t *pmd, *pmd_ref;
if (!pte_present(*pte) || pte_pfn(*pte) != pte_pfn(*pte_ref))
BUG();
return 0;
+#endif
}
int show_unhandled_signals = 1;
si_code = SEGV_MAPERR;
+ if (notify_page_fault(regs))
+ return;
/*
* We fault-in kernel-space virtual memory on-demand. The
if (vmalloc_fault(address) >= 0)
return;
}
- if (notify_page_fault(regs))
- return;
/*
* Don't take the mm semaphore here. If we fixup a prefetch
* fault we could otherwise deadlock.
goto bad_area_nosemaphore;
}
- if (notify_page_fault(regs))
- return;
-
if (likely(regs->flags & X86_EFLAGS_IF))
local_irq_enable();
if (!(vma->vm_flags & VM_GROWSDOWN))
goto bad_area;
if (error_code & PF_USER) {
- /* Allow userspace just enough access below the stack pointer
- * to let the 'enter' instruction work.
+ /*
+ * Accessing the stack below %sp is always a bug.
+ * The large cushion allows instructions like enter
+ * and pusha to work. ("enter $65535,$31" pushes
+ * 32 pointers and then decrements %sp by 65535.)
*/
if (address + 65536 + 32 * sizeof(unsigned long) < regs->sp)
goto bad_area;
tsk->maj_flt++;
else
tsk->min_flt++;
+
+#ifdef CONFIG_X86_32
+ /*
+ * Did it hit the DOS screen memory VA from vm86 mode?
+ */
+ if (v8086_mode(regs)) {
+ unsigned long bit = (address - 0xA0000) >> PAGE_SHIFT;
+ if (bit < 32)
+ tsk->thread.screen_bitmap |= 1 << bit;
+ }
+#endif
up_read(&mm->mmap_sem);
return;
if (show_unhandled_signals && unhandled_signal(tsk, SIGSEGV) &&
printk_ratelimit()) {
printk(
- "%s%s[%d]: segfault at %lx ip %lx sp %lx error %lx\n",
- tsk->pid > 1 ? KERN_INFO : KERN_EMERG,
- tsk->comm, tsk->pid, address, regs->ip,
- regs->sp, error_code);
+#ifdef CONFIG_X86_32
+ "%s%s[%d]: segfault at %lx ip %08lx sp %08lx error %lx",
+#else
+ "%s%s[%d]: segfault at %lx ip %lx sp %lx error %lx",
+#endif
+ task_pid_nr(tsk) > 1 ? KERN_INFO : KERN_EMERG,
+ tsk->comm, task_pid_nr(tsk), address, regs->ip,
+ regs->sp, error_code);
+ print_vma_addr(" in ", regs->ip);
+ printk("\n");
}
tsk->thread.cr2 = address;
else
printk(KERN_ALERT "Unable to handle kernel paging request");
printk(" at %016lx RIP: \n" KERN_ALERT, address);
- printk_address(regs->ip);
+ printk_address(regs->ip, 1);
dump_pagetable(address);
tsk->thread.cr2 = address;
tsk->thread.trap_no = 14;
void vmalloc_sync_all(void)
{
- /* Note that races in the updates of insync and start aren't
- problematic:
- insync can only get set bits added, and updates to start are only
- improving performance (without affecting correctness if undone). */
+ /*
+ * Note that races in the updates of insync and start aren't
+ * problematic: insync can only get set bits added, and updates to
+ * start are only improving performance (without affecting correctness
+ * if undone).
+ */
static DECLARE_BITMAP(insync, PTRS_PER_PGD);
static unsigned long start = VMALLOC_START & PGDIR_MASK;
unsigned long address;
projects / linux-2.6 / blobdiff