Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 161 insertions, 0 deletions

diff --git a/Documentation/process/magic-number.rst b/Documentation/process/magic-number.rst
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+Linux magic numbers
+===================
+
+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 them 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.
+
+Changelog::
+
+					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]
+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``
+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.
+
+HFS is another larger user of magic numbers - you can find them in
+``fs/hfs/hfs.h``.