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diff --git a/Documentation/magic-number.txt b/Documentation/magic-number.txt
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+This file is a registry of magic numbers which are in use.  When you
+add a magic number to a structure, you should also add it to this
+file, since it is best if the magic numbers used by various structures
+are unique.
+
+It is a *very* good idea to protect kernel data structures with magic
+numbers.  This allows you to check at run time whether (a) a structure
+has been clobbered, or (b) you've passed the wrong structure to a
+routine.  This last is especially useful --- particularly when you are
+passing pointers to structures via a void * pointer.  The tty code,
+for example, does this frequently to pass driver-specific and line
+discipline-specific structures back and forth.
+
+The way to use magic numbers is to declare then at the beginning of
+the structure, like so:
+
+struct tty_ldisc {
+	int	magic;
+	...
+};
+
+Please follow this discipline when you are adding future enhancements
+to the kernel!  It has saved me countless hours of debugging,
+especially in the screwy cases where an array has been overrun and
+structures following the array have been overwritten.  Using this
+discipline, these cases get detected quickly and safely.
+
+					Theodore Ts'o
+					31 Mar 94
+
+The magic table is current to Linux 2.1.55.
+
+					Michael Chastain
+					<mailto:mec@shout.net>
+					22 Sep 1997
+
+Now it should be up to date with Linux 2.1.112. Because
+we are in feature freeze time it is very unlikely that
+something will change before 2.2.x. The entries are
+sorted by number field.
+
+					Krzysztof G. Baranowski
+					<mailto: kgb@knm.org.pl>
+					29 Jul 1998
+
+Updated the magic table to Linux 2.5.45. Right over the feature freeze,
+but it is possible that some new magic numbers will sneak into the
+kernel before 2.6.x yet.
+
+					Petr Baudis
+					<pasky@ucw.cz>
+					03 Nov 2002
+
+Updated the magic table to Linux 2.5.74.
+
+					Fabian Frederick
+					<ffrederick@users.sourceforge.net>
+					09 Jul 2003
+
+
+Magic Name            Number      Structure            File
+===========================================================================
+PG_MAGIC              'P'         pg_{read,write}_hdr include/linux/pg.h
+CMAGIC                0x0111      user              include/linux/a.out.h
+MKISS_DRIVER_MAGIC    0x04bf      mkiss_channel     drivers/net/mkiss.h
+HDLC_MAGIC            0x239e      n_hdlc            drivers/char/n_hdlc.c
+APM_BIOS_MAGIC        0x4101      apm_user          arch/x86/kernel/apm_32.c
+CYCLADES_MAGIC        0x4359      cyclades_port     include/linux/cyclades.h
+DB_MAGIC              0x4442      fc_info           drivers/net/iph5526_novram.c
+DL_MAGIC              0x444d      fc_info           drivers/net/iph5526_novram.c
+FASYNC_MAGIC          0x4601      fasync_struct     include/linux/fs.h
+FF_MAGIC              0x4646      fc_info           drivers/net/iph5526_novram.c
+ISICOM_MAGIC          0x4d54      isi_port          include/linux/isicom.h
+PTY_MAGIC             0x5001                        drivers/char/pty.c
+PPP_MAGIC             0x5002      ppp               include/linux/if_pppvar.h
+SERIAL_MAGIC          0x5301      async_struct      include/linux/serial.h
+SSTATE_MAGIC          0x5302      serial_state      include/linux/serial.h
+SLIP_MAGIC            0x5302      slip              drivers/net/slip.h
+STRIP_MAGIC           0x5303      strip             drivers/net/strip.c
+X25_ASY_MAGIC         0x5303      x25_asy           drivers/net/x25_asy.h
+SIXPACK_MAGIC         0x5304      sixpack           drivers/net/hamradio/6pack.h
+AX25_MAGIC            0x5316      ax_disp           drivers/net/mkiss.h
+TTY_MAGIC             0x5401      tty_struct        include/linux/tty.h
+MGSL_MAGIC            0x5401      mgsl_info         drivers/char/synclink.c
+TTY_DRIVER_MAGIC      0x5402      tty_driver        include/linux/tty_driver.h
+MGSLPC_MAGIC          0x5402      mgslpc_info       drivers/char/pcmcia/synclink_cs.c
+TTY_LDISC_MAGIC       0x5403      tty_ldisc         include/linux/tty_ldisc.h
+USB_SERIAL_MAGIC      0x6702      usb_serial        drivers/usb/serial/usb-serial.h
+FULL_DUPLEX_MAGIC     0x6969                        drivers/net/ethernet/dec/tulip/de2104x.c
+USB_BLUETOOTH_MAGIC   0x6d02      usb_bluetooth     drivers/usb/class/bluetty.c
+RFCOMM_TTY_MAGIC      0x6d02                        net/bluetooth/rfcomm/tty.c
+USB_SERIAL_PORT_MAGIC 0x7301      usb_serial_port   drivers/usb/serial/usb-serial.h
+CG_MAGIC              0x00090255  ufs_cylinder_group include/linux/ufs_fs.h
+RPORT_MAGIC           0x00525001  r_port            drivers/char/rocket_int.h
+LSEMAGIC              0x05091998  lse               drivers/fc4/fc.c
+GDTIOCTL_MAGIC        0x06030f07  gdth_iowr_str     drivers/scsi/gdth_ioctl.h
+RIEBL_MAGIC           0x09051990                    drivers/net/atarilance.c
+NBD_REQUEST_MAGIC     0x12560953  nbd_request       include/linux/nbd.h
+RED_MAGIC2            0x170fc2a5  (any)             mm/slab.c
+BAYCOM_MAGIC          0x19730510  baycom_state      drivers/net/baycom_epp.c
+ISDN_X25IFACE_MAGIC   0x1e75a2b9  isdn_x25iface_proto_data
+                                                    drivers/isdn/isdn_x25iface.h
+ECP_MAGIC             0x21504345  cdkecpsig         include/linux/cdk.h
+LSOMAGIC              0x27091997  lso               drivers/fc4/fc.c
+LSMAGIC               0x2a3b4d2a  ls                drivers/fc4/fc.c
+WANPIPE_MAGIC         0x414C4453  sdla_{dump,exec}  include/linux/wanpipe.h
+CS_CARD_MAGIC         0x43525553  cs_card           sound/oss/cs46xx.c
+LABELCL_MAGIC         0x4857434c  labelcl_info_s    include/asm/ia64/sn/labelcl.h
+ISDN_ASYNC_MAGIC      0x49344C01  modem_info        include/linux/isdn.h
+CTC_ASYNC_MAGIC       0x49344C01  ctc_tty_info      drivers/s390/net/ctctty.c
+ISDN_NET_MAGIC        0x49344C02  isdn_net_local_s  drivers/isdn/i4l/isdn_net_lib.h
+SAVEKMSG_MAGIC2       0x4B4D5347  savekmsg          arch/*/amiga/config.c
+CS_STATE_MAGIC        0x4c4f4749  cs_state          sound/oss/cs46xx.c
+SLAB_C_MAGIC          0x4f17a36d  kmem_cache        mm/slab.c
+COW_MAGIC             0x4f4f4f4d  cow_header_v1     arch/um/drivers/ubd_user.c
+I810_CARD_MAGIC       0x5072696E  i810_card         sound/oss/i810_audio.c
+TRIDENT_CARD_MAGIC    0x5072696E  trident_card      sound/oss/trident.c
+ROUTER_MAGIC          0x524d4157  wan_device        [in wanrouter.h pre 3.9]
+SCC_MAGIC             0x52696368  gs_port           drivers/char/scc.h
+SAVEKMSG_MAGIC1       0x53415645  savekmsg          arch/*/amiga/config.c
+GDA_MAGIC             0x58464552  gda               arch/mips/include/asm/sn/gda.h
+RED_MAGIC1            0x5a2cf071  (any)             mm/slab.c
+EEPROM_MAGIC_VALUE    0x5ab478d2  lanai_dev         drivers/atm/lanai.c
+HDLCDRV_MAGIC         0x5ac6e778  hdlcdrv_state     include/linux/hdlcdrv.h
+PCXX_MAGIC            0x5c6df104  channel           drivers/char/pcxx.h
+KV_MAGIC              0x5f4b565f  kernel_vars_s     arch/mips/include/asm/sn/klkernvars.h
+I810_STATE_MAGIC      0x63657373  i810_state        sound/oss/i810_audio.c
+TRIDENT_STATE_MAGIC   0x63657373  trient_state      sound/oss/trident.c
+M3_CARD_MAGIC         0x646e6f50  m3_card           sound/oss/maestro3.c
+FW_HEADER_MAGIC       0x65726F66  fw_header         drivers/atm/fore200e.h
+SLOT_MAGIC            0x67267321  slot              drivers/hotplug/cpqphp.h
+SLOT_MAGIC            0x67267322  slot              drivers/hotplug/acpiphp.h
+LO_MAGIC              0x68797548  nbd_device        include/linux/nbd.h
+OPROFILE_MAGIC        0x6f70726f  super_block       drivers/oprofile/oprofilefs.h
+M3_STATE_MAGIC        0x734d724d  m3_state          sound/oss/maestro3.c
+VMALLOC_MAGIC         0x87654320  snd_alloc_track   sound/core/memory.c
+KMALLOC_MAGIC         0x87654321  snd_alloc_track   sound/core/memory.c
+PWC_MAGIC             0x89DC10AB  pwc_device        drivers/usb/media/pwc.h
+NBD_REPLY_MAGIC       0x96744668  nbd_reply         include/linux/nbd.h
+ENI155_MAGIC          0xa54b872d  midway_eprom	    drivers/atm/eni.h
+SCI_MAGIC             0xbabeface  gs_port           drivers/char/sh-sci.h
+CODA_MAGIC            0xC0DAC0DA  coda_file_info    fs/coda/coda_fs_i.h
+DPMEM_MAGIC           0xc0ffee11  gdt_pci_sram      drivers/scsi/gdth.h
+YAM_MAGIC             0xF10A7654  yam_port          drivers/net/hamradio/yam.c
+CCB_MAGIC             0xf2691ad2  ccb               drivers/scsi/ncr53c8xx.c
+QUEUE_MAGIC_FREE      0xf7e1c9a3  queue_entry       drivers/scsi/arm/queue.c
+QUEUE_MAGIC_USED      0xf7e1cc33  queue_entry       drivers/scsi/arm/queue.c
+HTB_CMAGIC            0xFEFAFEF1  htb_class         net/sched/sch_htb.c
+NMI_MAGIC             0x48414d4d455201 nmi_s        arch/mips/include/asm/sn/nmi.h
+
+Note that there are also defined special per-driver magic numbers in sound
+memory management. See include/sound/sndmagic.h for complete list of them. Many
+OSS sound drivers have their magic numbers constructed from the soundcard PCI
+ID - these are not listed here as well.
+
+IrDA subsystem also uses large number of own magic numbers, see
+include/net/irda/irda.h for a complete list of them.
+
+HFS is another larger user of magic numbers - you can find them in
+fs/hfs/hfs.h.