1.1 --- a/xen/arch/x86/traps.c	Thu Oct 30 14:53:24 2008 +0000
     1.2 +++ b/xen/arch/x86/traps.c	Thu Oct 30 15:04:27 2008 +0000
     1.3 @@ -1030,7 +1030,7 @@ static int handle_gdt_ldt_mapping_fault(
     1.4  #endif
     1.5  
     1.6  static int __spurious_page_fault(
     1.7 -    unsigned long addr, struct cpu_user_regs *regs)
     1.8 +    unsigned long addr, unsigned int error_code)
     1.9  {
    1.10      unsigned long mfn, cr3 = read_cr3();
    1.11  #if CONFIG_PAGING_LEVELS >= 4
    1.12 @@ -1052,17 +1052,17 @@ static int __spurious_page_fault(
    1.13          return 0;
    1.14  
    1.15      /* Reserved bit violations are never spurious faults. */
    1.16 -    if ( regs->error_code & PFEC_reserved_bit )
    1.17 +    if ( error_code & PFEC_reserved_bit )
    1.18          return 0;
    1.19  
    1.20      required_flags  = _PAGE_PRESENT;
    1.21 -    if ( regs->error_code & PFEC_write_access )
    1.22 +    if ( error_code & PFEC_write_access )
    1.23          required_flags |= _PAGE_RW;
    1.24 -    if ( regs->error_code & PFEC_user_mode )
    1.25 +    if ( error_code & PFEC_user_mode )
    1.26          required_flags |= _PAGE_USER;
    1.27  
    1.28      disallowed_flags = 0;
    1.29 -    if ( regs->error_code & PFEC_insn_fetch )
    1.30 +    if ( error_code & PFEC_insn_fetch )
    1.31          disallowed_flags |= _PAGE_NX;
    1.32  
    1.33      mfn = cr3 >> PAGE_SHIFT;
    1.34 @@ -1120,7 +1120,7 @@ static int __spurious_page_fault(
    1.35      dprintk(XENLOG_WARNING, "Spurious fault in domain %u:%u "
    1.36              "at addr %lx, e/c %04x\n",
    1.37              current->domain->domain_id, current->vcpu_id,
    1.38 -            addr, regs->error_code);
    1.39 +            addr, error_code);
    1.40  #if CONFIG_PAGING_LEVELS >= 4
    1.41      dprintk(XENLOG_WARNING, " l4e = %"PRIpte"\n", l4e_get_intpte(l4e));
    1.42  #endif
    1.43 @@ -1129,14 +1129,11 @@ static int __spurious_page_fault(
    1.44  #endif
    1.45      dprintk(XENLOG_WARNING, " l2e = %"PRIpte"\n", l2e_get_intpte(l2e));
    1.46      dprintk(XENLOG_WARNING, " l1e = %"PRIpte"\n", l1e_get_intpte(l1e));
    1.47 -#ifndef NDEBUG
    1.48 -    show_registers(regs);
    1.49 -#endif
    1.50      return 1;
    1.51  }
    1.52  
    1.53  static int spurious_page_fault(
    1.54 -    unsigned long addr, struct cpu_user_regs *regs)
    1.55 +    unsigned long addr, unsigned int error_code)
    1.56  {
    1.57      unsigned long flags;
    1.58      int           is_spurious;
    1.59 @@ -1146,7 +1143,7 @@ static int spurious_page_fault(
    1.60       * page tables from becoming invalid under our feet during the walk.
    1.61       */
    1.62      local_irq_save(flags);
    1.63 -    is_spurious = __spurious_page_fault(addr, regs);
    1.64 +    is_spurious = __spurious_page_fault(addr, error_code);
    1.65      local_irq_restore(flags);
    1.66  
    1.67      return is_spurious;
    1.68 @@ -1208,9 +1205,13 @@ static int fixup_page_fault(unsigned lon
    1.69  asmlinkage void do_page_fault(struct cpu_user_regs *regs)
    1.70  {
    1.71      unsigned long addr, fixup;
    1.72 +    unsigned int error_code;
    1.73  
    1.74      addr = read_cr2();
    1.75  
    1.76 +    /* fixup_page_fault() might change regs->error_code, so cache it here. */
    1.77 +    error_code = regs->error_code;
    1.78 +
    1.79      DEBUGGER_trap_entry(TRAP_page_fault, regs);
    1.80  
    1.81      perfc_incr(page_faults);
    1.82 @@ -1220,7 +1221,7 @@ asmlinkage void do_page_fault(struct cpu
    1.83  
    1.84      if ( unlikely(!guest_mode(regs)) )
    1.85      {
    1.86 -        if ( spurious_page_fault(addr, regs) )
    1.87 +        if ( spurious_page_fault(addr, error_code) )
    1.88              return;
    1.89  
    1.90          if ( likely((fixup = search_exception_table(regs->eip)) != 0) )
    1.91 @@ -1239,11 +1240,11 @@ asmlinkage void do_page_fault(struct cpu
    1.92          panic("FATAL PAGE FAULT\n"
    1.93                "[error_code=%04x]\n"
    1.94                "Faulting linear address: %p\n",
    1.95 -              regs->error_code, _p(addr));
    1.96 +              error_code, _p(addr));
    1.97      }
    1.98  
    1.99      if ( unlikely(current->domain->arch.suppress_spurious_page_faults
   1.100 -                  && spurious_page_fault(addr, regs)) )
   1.101 +                  && spurious_page_fault(addr, error_code)) )
   1.102          return;
   1.103  
   1.104      propagate_page_fault(addr, regs->error_code);