tools/lldbmacros/pmap.py

   1 from xnu import *
   2 import xnudefines
   3 from kdp import *
   4 from utils import *
   5
   6 def ReadPhysInt(phys_addr, bitsize = 64, cpuval = None):
   7     """ Read a physical memory data based on address.
   8         params:
   9             phys_addr : int - Physical address to read
  10             bitsize   : int - defines how many bytes to read. defaults to 64 bit
  11             cpuval    : None (optional)
  12         returns:
  13             int - int value read from memory. in case of failure 0xBAD10AD is returned.
  14     """
  15     if "kdp" == GetConnectionProtocol():
  16         return KDPReadPhysMEM(phys_addr, bitsize)
  17
  18     #NO KDP. Attempt to use physical memory
  19     paddr_in_kva = kern.PhysToKernelVirt(long(phys_addr))
  20     if paddr_in_kva :
  21         if bitsize == 64 :
  22             return kern.GetValueFromAddress(paddr_in_kva, 'uint64_t *').GetSBValue().Dereference().GetValueAsUnsigned()
  23         if bitsize == 32 :
  24             return kern.GetValueFromAddress(paddr_in_kva, 'uint32_t *').GetSBValue().Dereference().GetValueAsUnsigned()
  25         if bitsize == 16 :
  26             return kern.GetValueFromAddress(paddr_in_kva, 'uint16_t *').GetSBValue().Dereference().GetValueAsUnsigned()
  27         if bitsize == 8 :
  28             return kern.GetValueFromAddress(paddr_in_kva, 'uint8_t *').GetSBValue().Dereference().GetValueAsUnsigned()
  29     return 0xBAD10AD
  30
  31 @lldb_command('readphys')
  32 def ReadPhys(cmd_args = None):
  33     """ Reads the specified untranslated address
  34         The argument is interpreted as a physical address, and the 64-bit word
  35         addressed is displayed.
  36         usage: readphys <nbits> <address>
  37         nbits: 8,16,32,64
  38         address: 1234 or 0x1234
  39     """
  40     if cmd_args == None or len(cmd_args) < 2:
  41         print "Insufficient arguments.", ReadPhys.__doc__
  42         return False
  43     else:
  44         nbits = ArgumentStringToInt(cmd_args[0])
  45         phys_addr = ArgumentStringToInt(cmd_args[1])
  46         print "{0: <#x}".format(ReadPhysInt(phys_addr, nbits))
  47     return True
  48
  49 lldb_alias('readphys8', 'readphys 8 ')
  50 lldb_alias('readphys16', 'readphys 16 ')
  51 lldb_alias('readphys32', 'readphys 32 ')
  52 lldb_alias('readphys64', 'readphys 64 ')
  53
  54 def KDPReadPhysMEM(address, bits):
  55     """ Setup the state for READPHYSMEM64 commands for reading data via kdp
  56         params:
  57             address : int - address where to read the data from
  58             bits : int - number of bits in the intval (8/16/32/64)
  59         returns:
  60             int: read value from memory.
  61             0xBAD10AD: if failed to read data.
  62     """
  63     retval = 0xBAD10AD
  64     if "kdp" != GetConnectionProtocol():
  65         print "Target is not connected over kdp. Nothing to do here."
  66         return retval
  67
  68     input_address = unsigned(addressof(kern.globals.manual_pkt.input))
  69     len_address = unsigned(addressof(kern.globals.manual_pkt.len))
  70     data_address = unsigned(addressof(kern.globals.manual_pkt.data))
  71     if not WriteInt32ToMemoryAddress(0, input_address):
  72         return retval
  73
  74     kdp_pkt_size = GetType('kdp_readphysmem64_req_t').GetByteSize()
  75     if not WriteInt32ToMemoryAddress(kdp_pkt_size, len_address):
  76         return retval
  77
  78     data_addr = int(addressof(kern.globals.manual_pkt))
  79     pkt = kern.GetValueFromAddress(data_addr, 'kdp_readphysmem64_req_t *')
  80
  81     header_value =GetKDPPacketHeaderInt(request=GetEnumValue('kdp_req_t::KDP_READPHYSMEM64'), length=kdp_pkt_size)
  82
  83     if ( WriteInt64ToMemoryAddress((header_value), int(addressof(pkt.hdr))) and
  84          WriteInt64ToMemoryAddress(address, int(addressof(pkt.address))) and
  85          WriteInt32ToMemoryAddress((bits/8), int(addressof(pkt.nbytes))) and
  86          WriteInt16ToMemoryAddress(xnudefines.lcpu_self, int(addressof(pkt.lcpu)))
  87          ):
  88
  89         if WriteInt32ToMemoryAddress(1, input_address):
  90             # now read data from the kdp packet
  91             data_address = unsigned(addressof(kern.GetValueFromAddress(int(addressof(kern.globals.manual_pkt.data)), 'kdp_readphysmem64_reply_t *').data))
  92             if bits == 64 :
  93                 retval =  kern.GetValueFromAddress(data_address, 'uint64_t *').GetSBValue().Dereference().GetValueAsUnsigned()
  94             if bits == 32 :
  95                 retval =  kern.GetValueFromAddress(data_address, 'uint32_t *').GetSBValue().Dereference().GetValueAsUnsigned()
  96             if bits == 16 :
  97                 retval =  kern.GetValueFromAddress(data_address, 'uint16_t *').GetSBValue().Dereference().GetValueAsUnsigned()
  98             if bits == 8 :
  99                 retval =  kern.GetValueFromAddress(data_address, 'uint8_t *').GetSBValue().Dereference().GetValueAsUnsigned()
 100     return retval
 101
 102
 103 def KDPWritePhysMEM(address, intval, bits):
 104     """ Setup the state for WRITEPHYSMEM64 commands for saving data in kdp
 105         params:
 106             address : int - address where to save the data
 107             intval : int - integer value to be stored in memory
 108             bits : int - number of bits in the intval (8/16/32/64)
 109         returns:
 110             boolean: True if the write succeeded.
 111     """
 112     if "kdp" != GetConnectionProtocol():
 113         print "Target is not connected over kdp. Nothing to do here."
 114         return False
 115     input_address = unsigned(addressof(kern.globals.manual_pkt.input))
 116     len_address = unsigned(addressof(kern.globals.manual_pkt.len))
 117     data_address = unsigned(addressof(kern.globals.manual_pkt.data))
 118     if not WriteInt32ToMemoryAddress(0, input_address):
 119         return False
 120
 121     kdp_pkt_size = GetType('kdp_writephysmem64_req_t').GetByteSize()
 122     if not WriteInt32ToMemoryAddress(kdp_pkt_size, len_address):
 123         return False
 124
 125     data_addr = int(addressof(kern.globals.manual_pkt))
 126     pkt = kern.GetValueFromAddress(data_addr, 'kdp_writephysmem64_req_t *')
 127
 128     header_value =GetKDPPacketHeaderInt(request=GetEnumValue('kdp_req_t::KDP_WRITEPHYSMEM64'), length=kdp_pkt_size)
 129
 130     if ( WriteInt64ToMemoryAddress((header_value), int(addressof(pkt.hdr))) and
 131          WriteInt64ToMemoryAddress(address, int(addressof(pkt.address))) and
 132          WriteInt32ToMemoryAddress((bits/8), int(addressof(pkt.nbytes))) and
 133          WriteInt16ToMemoryAddress(xnudefines.lcpu_self, int(addressof(pkt.lcpu)))
 134          ):
 135
 136         if bits == 8:
 137             if not WriteInt8ToMemoryAddress(intval, int(addressof(pkt.data))):
 138                 return False
 139         if bits == 16:
 140             if not WriteInt16ToMemoryAddress(intval, int(addressof(pkt.data))):
 141                 return False
 142         if bits == 32:
 143             if not WriteInt32ToMemoryAddress(intval, int(addressof(pkt.data))):
 144                 return False
 145         if bits == 64:
 146             if not WriteInt64ToMemoryAddress(intval, int(addressof(pkt.data))):
 147                 return False
 148         if WriteInt32ToMemoryAddress(1, input_address):
 149             return True
 150     return False
 151
 152
 153 def WritePhysInt(phys_addr, int_val, bitsize = 64):
 154     """ Write and integer value in a physical memory data based on address.
 155         params:
 156             phys_addr : int - Physical address to read
 157             int_val   : int - int value to write in memory
 158             bitsize   : int - defines how many bytes to read. defaults to 64 bit
 159         returns:
 160             bool - True if write was successful.
 161     """
 162     if "kdp" == GetConnectionProtocol():
 163         if not KDPWritePhysMEM(phys_addr, int_val, bitsize):
 164             print "Failed to write via KDP."
 165             return False
 166         return True
 167     #We are not connected via KDP. So do manual math and savings.
 168     print "Failed: Write to physical memory is not supported for %s connection." % GetConnectionProtocol()
 169     return False
 170
 171 @lldb_command('writephys')
 172 def WritePhys(cmd_args=None):
 173     """ writes to the specified untranslated address
 174         The argument is interpreted as a physical address, and the 64-bit word
 175         addressed is displayed.
 176         usage: writephys <nbits> <address> <value>
 177         nbits: 8,16,32,64
 178         address: 1234 or 0x1234
 179         value: int value to be written
 180         ex. (lldb)writephys 16 0x12345abcd 0x25
 181     """
 182     if cmd_args == None or len(cmd_args) < 3:
 183         print "Invalid arguments.", WritePhys.__doc__
 184     else:
 185         nbits = ArgumentStringToInt(cmd_args[0])
 186         phys_addr = ArgumentStringToInt(cmd_args[1])
 187         int_value = ArgumentStringToInt(cmd_args[2])
 188         print WritePhysInt(phys_addr, int_value, nbits)
 189
 190
 191 lldb_alias('writephys8', 'writephys 8 ')
 192 lldb_alias('writephys16', 'writephys 16 ')
 193 lldb_alias('writephys32', 'writephys 32 ')
 194 lldb_alias('writephys64', 'writephys 64 ')
 195
 196 def _PT_Step(paddr, index, verbose_level = vSCRIPT):
 197     """
 198      Step to lower-level page table and print attributes
 199        paddr: current page table entry physical address
 200        index: current page table entry index (0..511)
 201        verbose_level:    vHUMAN: print nothing
 202                          vSCRIPT: print basic information
 203                          vDETAIL: print basic information and hex table dump
 204      returns: (pt_paddr, pt_valid, pt_large)
 205        pt_paddr: next level page table entry physical address
 206                       or null if invalid
 207        pt_valid: 1 if $kgm_pt_paddr is valid, 0 if the walk
 208                       should be aborted
 209        pt_large: 1 if kgm_pt_paddr is a page frame address
 210                       of a large page and not another page table entry
 211     """
 212     entry_addr = paddr + (8 * index)
 213     entry = ReadPhysInt(entry_addr, 64, xnudefines.lcpu_self )
 214     out_string = ''
 215     if verbose_level >= vDETAIL:
 216         for pte_loop in range(0, 512):
 217             paddr_tmp = paddr + (8 * pte_loop)
 218             out_string += "{0: <#020x}:\t {1: <#020x}\n".format(paddr_tmp, ReadPhysInt(paddr_tmp, 64, xnudefines.lcpu_self))
 219     paddr_mask = ~((0xfff<<52) | 0xfff)
 220     paddr_large_mask =  ~((0xfff<<52) | 0x1fffff)
 221     pt_valid = False
 222     pt_large = False
 223     pt_paddr = 0
 224     if verbose_level < vSCRIPT:
 225         if entry & 0x1 :
 226             pt_valid = True
 227             pt_large = False
 228             pt_paddr = entry & paddr_mask
 229             if entry & (0x1 <<7):
 230                 pt_large = True
 231                 pt_paddr = entry & paddr_large_mask
 232     else:
 233         out_string+= "{0: <#020x}:\n\t{1:#020x}\n\t".format(entry_addr, entry)
 234         if entry & 0x1:
 235             out_string += " valid"
 236             pt_paddr = entry & paddr_mask
 237             pt_valid = True
 238         else:
 239             out_string += " invalid"
 240             pt_paddr = 0
 241             pt_valid = False
 242             #Stop decoding other bits
 243             entry = 0
 244         if entry & (0x1 << 1):
 245             out_string += " writable"
 246         else:
 247             out_string += " read-only"
 248
 249         if entry & (0x1 << 2):
 250             out_string += " user"
 251         else:
 252             out_string += " supervisor"
 253
 254         if entry & (0x1 << 3):
 255             out_string += " PWT"
 256
 257         if entry & (0x1 << 4):
 258             out_string += " PCD"
 259
 260         if entry & (0x1 << 5):
 261             out_string += " accessed"
 262
 263         if entry & (0x1 << 6):
 264             out_string += " dirty"
 265
 266         if entry & (0x1 << 7):
 267             out_string += " large"
 268             pt_large = True
 269         else:
 270             pt_large = False
 271
 272         if entry & (0x1 << 8):
 273             out_string += " global"
 274
 275         if entry & (0x3 << 9):
 276             out_string += " avail:{0:x}".format((entry >> 9) & 0x3)
 277
 278         if entry & (0x1 << 63):
 279             out_string += " noexec"
 280     print out_string
 281     return (pt_paddr, pt_valid, pt_large)
 282
 283
 284
 285
 286 def _PmapL4Walk(pmap_addr_val,vaddr, verbose_level = vSCRIPT):
 287     """ Walk the l4 pmap entry.
 288         params: pmap_addr_val - core.value representing kernel data of type pmap_addr_t
 289         vaddr : int - virtual address to walk
 290     """
 291     is_cpu64_bit = int(kern.globals.cpu_64bit)
 292     pt_paddr = unsigned(pmap_addr_val)
 293     pt_valid = (unsigned(pmap_addr_val) != 0)
 294     pt_large = 0
 295     pframe_offset = 0
 296     if pt_valid and is_cpu64_bit:
 297         # Lookup bits 47:39 of linear address in PML4T
 298         pt_index = (vaddr >> 39) & 0x1ff
 299         pframe_offset = vaddr & 0x7fffffffff
 300         if verbose_level > vHUMAN :
 301             print "pml4 (index {0:d}):".format(pt_index)
 302         (pt_paddr, pt_valid, pt_large) = _PT_Step(pt_paddr, pt_index, verbose_level)
 303     if pt_valid:
 304         # Lookup bits 38:30 of the linear address in PDPT
 305         pt_index = (vaddr >> 30) & 0x1ff
 306         pframe_offset = vaddr & 0x3fffffff
 307         if verbose_level > vHUMAN:
 308             print "pdpt (index {0:d}):".format(pt_index)
 309         (pt_paddr, pt_valid, pt_large) = _PT_Step(pt_paddr, pt_index, verbose_level)
 310     if pt_valid and not pt_large:
 311         #Lookup bits 29:21 of the linear address in PDPT
 312         pt_index = (vaddr >> 21) & 0x1ff
 313         pframe_offset = vaddr & 0x1fffff
 314         if verbose_level > vHUMAN:
 315             print "pdt (index {0:d}):".format(pt_index)
 316         (pt_paddr, pt_valid, pt_large) = _PT_Step(pt_paddr, pt_index, verbose_level)
 317     if pt_valid and not pt_large:
 318         #Lookup bits 20:21 of linear address in PT
 319         pt_index = (vaddr >> 12) & 0x1ff
 320         pframe_offset = vaddr & 0xfff
 321         if verbose_level > vHUMAN:
 322             print "pt (index {0:d}):".format(pt_index)
 323         (pt_paddr, pt_valid, pt_large) = _PT_Step(pt_paddr, pt_index, verbose_level)
 324     paddr = 0
 325     paddr_isvalid = False
 326     if pt_valid:
 327         paddr = pt_paddr + pframe_offset
 328         paddr_isvalid = True
 329
 330     if verbose_level > vHUMAN:
 331         if paddr_isvalid:
 332             pvalue = ReadPhysInt(paddr, 32, xnudefines.lcpu_self)
 333             print "phys {0: <#020x}: {1: <#020x}".format(paddr, pvalue)
 334         else:
 335             print "no translation"
 336
 337     return
 338
 339 def _PmapWalkARMLevel1Section(tte, vaddr, verbose_level = vSCRIPT):
 340     paddr = 0
 341     out_string = ""
 342     #Supersection or just section?
 343     if (tte & 0x40000) == 0x40000:
 344         paddr = ( (tte & 0xFF000000) | (vaddr & 0x00FFFFFF) )
 345     else:
 346         paddr = ( (tte & 0xFFF00000) | (vaddr & 0x000FFFFF) )
 347
 348     if verbose_level >= vSCRIPT:
 349         out_string += "{0: <#020x}\n\t{1: <#020x}\n\t".format(addressof(tte), tte)
 350         #bit [1:0] evaluated in PmapWalkARM
 351         # B bit 2
 352         b_bit = (tte & 0x4) >> 2
 353         # C bit 3
 354         c_bit = (tte & 0x8) >> 3
 355         #XN bit 4
 356         if (tte & 0x10) :
 357             out_string += "no-execute"
 358         else:
 359             out_string += "execute"
 360         #Domain bit [8:5] if not supersection
 361         if (tte & 0x40000) == 0x0:
 362             out_string += " domain ({:d})".format(((tte & 0x1e0) >> 5) )
 363         #IMP bit 9
 364         out_string += " imp({:d})".format( ((tte & 0x200) >> 9) )
 365         # AP bit 15 and [11:10] merged to a single 3 bit value
 366         access = ( (tte & 0xc00) >> 10 ) | ((tte & 0x8000) >> 13)
 367         out_string += xnudefines.arm_level2_access_strings[access]
 368
 369         #TEX bit [14:12]
 370         tex_bits = ((tte & 0x7000) >> 12)
 371         #Print TEX, C , B all together
 372         out_string += " TEX:C:B({:d}{:d}{:d}:{:d}:{:d})".format(
 373                                                                     1 if (tex_bits & 0x4) else 0,
 374                                                                     1 if (tex_bits & 0x2) else 0,
 375                                                                     1 if (tex_bits & 0x1) else 0,
 376                                                                     c_bit,
 377                                                                     b_bit
 378                                                                     )
 379         # S bit 16
 380         if tte & 0x10000:
 381             out_string += " shareable"
 382         else:
 383             out_string += " not-shareable"
 384         # nG bit 17
 385         if tte & 0x20000 :
 386             out_string += " not-global"
 387         else:
 388             out_string += " global"
 389         # Supersection bit 18
 390         if tte & 0x40000:
 391             out_string += " supersection"
 392         else:
 393             out_string += " section"
 394         #NS bit 19
 395         if tte & 0x80000 :
 396             out_string += " no-secure"
 397         else:
 398             out_string += " secure"
 399
 400     print out_string
 401     return paddr
 402
 403
 404
 405 def _PmapWalkARMLevel2(tte, vaddr, verbose_level = vSCRIPT):
 406     """ Pmap walk the level 2 tte.
 407         params:
 408           tte - value object
 409           vaddr - int
 410         returns: str - description of the tte + additional informaiton based on verbose_level
 411     """
 412     pte_base = kern.PhysToKernelVirt(tte & 0xFFFFFC00)
 413     pte_index = (vaddr >> 12) & 0xFF
 414     pte_base_val = kern.GetValueFromAddress(pte_base, 'pt_entry_t *')
 415     pte = pte_base_val[pte_index]
 416     out_string = ''
 417     if verbose_level >= vSCRIPT:
 418         out_string += "{0: <#020x}\n\t{1: <#020x}\n\t".format(addressof(tte), tte)
 419         # bit [1:0] evaluated in PmapWalkARM
 420         # NS bit 3
 421         if tte & 0x8:
 422             out_string += ' no-secure'
 423         else:
 424             out_string += ' secure'
 425         #Domain bit [8:5]
 426         out_string += " domain({:d})".format(((tte & 0x1e0) >> 5))
 427         # IMP bit 9
 428         out_string += " imp({:d})".format( ((tte & 0x200) >> 9))
 429         out_string += "\n"
 430     if verbose_level >= vSCRIPT:
 431         out_string += "second-level table (index {:d}):\n".format(pte_index)
 432     if verbose_level >= vDETAIL:
 433         for i in range(256):
 434             tmp = pte_base_val[i]
 435             out_string += "{0: <#020x}:\t{1: <#020x}\n".format(addressof(tmp), unsigned(tmp))
 436
 437     paddr = 0
 438     if pte & 0x2:
 439         paddr = (unsigned(pte) & 0xFFFFF000) | (vaddr & 0xFFF)
 440
 441     if verbose_level >= vSCRIPT:
 442         out_string += " {0: <#020x}\n\t{1: <#020x}\n\t".format(addressof(pte), unsigned(pte))
 443         if (pte & 0x3) == 0x0:
 444             out_string += " invalid"
 445         else:
 446             if (pte & 0x3) == 0x1:
 447                 out_string += " large"
 448                 # XN bit 15
 449                 if pte & 0x8000 == 0x8000:
 450                     out_string+= " no-execute"
 451                 else:
 452                     out_string += " execute"
 453             else:
 454                 out_string += " small"
 455                 # XN bit 0
 456                 if (pte & 0x1) == 0x01:
 457                     out_string += " no-execute"
 458                 else:
 459                     out_string += " execute"
 460             # B bit 2
 461             b_bit = (pte & 0x4) >> 2
 462             c_bit = (pte & 0x8) >> 3
 463             # AP bit 9 and [5:4], merged to a single 3-bit value
 464             access = (pte & 0x30) >> 4 | (pte & 0x200) >> 7
 465             out_string += xnudefines.arm_level2_access_strings[access]
 466
 467             #TEX bit [14:12] for large, [8:6] for small
 468             tex_bits = ((pte & 0x1c0) >> 6)
 469             if (pte & 0x3) == 0x1:
 470                 tex_bits = ((pte & 0x7000) >> 12)
 471
 472             # Print TEX, C , B alltogether
 473             out_string += " TEX:C:B({:d}{:d}{:d}:{:d}:{:d})".format(
 474                                                                     1 if (tex_bits & 0x4) else 0,
 475                                                                     1 if (tex_bits & 0x2) else 0,
 476                                                                     1 if (tex_bits & 0x1) else 0,
 477                                                                     c_bit,
 478                                                                     b_bit
 479                                                                     )
 480             # S bit 10
 481             if pte & 0x400 :
 482                 out_string += " shareable"
 483             else:
 484                 out_string += " not-shareable"
 485
 486             # nG bit 11
 487             if pte & 0x800:
 488                 out_string += " not-global"
 489             else:
 490                 out_string += " global"
 491     print out_string
 492     return paddr
 493     #end of level 2 walking of arm
 494
 495
 496 def PmapWalkARM(pmap, vaddr, verbose_level = vHUMAN):
 497     """ Pmap walking for ARM kernel.
 498         params:
 499           pmapval: core.value - representing pmap_t in kernel
 500           vaddr:  int     - integer representing virtual address to walk
 501     """
 502     paddr = 0
 503     # shift by TTESHIFT (20) to get tte index
 504     tte_index = ((vaddr - unsigned(pmap.min)) >> 20 )
 505     tte = pmap.tte[tte_index]
 506     if verbose_level >= vSCRIPT:
 507         print "First-level table (index {:d}):".format(tte_index)
 508     if verbose_level >= vDETAIL:
 509         for i in range(0, 4096):
 510             ptr = unsigned(addressof(pmap.tte[i]))
 511             val = unsigned(pmap.tte[i])
 512             print "{0: <#020x}:\t {1: <#020x}".format(ptr, val)
 513     if (tte & 0x3) == 0x1:
 514         paddr = _PmapWalkARMLevel2(tte, vaddr, verbose_level)
 515     elif (tte & 0x3) == 0x2 :
 516         paddr = _PmapWalkARMLevel1Section(tte, vaddr, verbose_level)
 517     else:
 518         paddr = 0
 519         if verbose_level >= vSCRIPT:
 520             print "Invalid First-Level Translation Table Entry: {0: #020x}".format(tte)
 521
 522     if verbose_level >= vHUMAN:
 523         if paddr:
 524             print "Translation of {:#x} is {:#x}.".format(vaddr, paddr)
 525         else:
 526             print "(no translation)"
 527
 528     return paddr
 529
 530 def PmapWalkX86_64(pmapval, vaddr):
 531     """
 532         params: pmapval - core.value representing pmap_t in kernel
 533         vaddr:  int     - int representing virtual address to walk
 534     """
 535     _PmapL4Walk(pmapval.pm_cr3, vaddr, config['verbosity'])
 536
 537 def assert_64bit(val):
 538     assert(val < 2**64)
 539
 540 def PmapWalk(pmap, vaddr, verbose_level = vHUMAN):
 541     if kern.arch == 'x86_64':
 542         return PmapWalkX86_64(pmap, vaddr)
 543     elif kern.arch == 'arm':
 544         return PmapWalkARM(pmap, vaddr, verbose_level)
 545     else:
 546         raise NotImplementedError("PmapWalk does not support {0}".format(kern.arch))
 547
 548 @lldb_command('pmap_walk')
 549 def PmapWalkHelper(cmd_args=None):
 550     """ Perform a page-table walk in <pmap> for <virtual_address>.
 551         Syntax: (lldb) pmap_walk <pmap> <virtual_address> [-v]
 552             Multiple -v's can be specified for increased verbosity
 553     """
 554     if cmd_args == None or len(cmd_args) < 2:
 555         raise ArgumentError("Too few arguments to pmap_walk.")
 556
 557     pmap = kern.GetValueAsType(cmd_args[0], 'pmap_t')
 558     addr = unsigned(kern.GetValueFromAddress(cmd_args[1], 'void *'))
 559     PmapWalk(pmap, addr, config['verbosity'])
 560     return