NAME
mod - module information and loading of symbols and debugging data
SYNOPSIS
mod [ -s module [objfile] | -d module | -S [directory] | -D | -r | -o ]
DESCRIPTION
With no arguments, this command displays basic information of the currently
installed modules, consisting of the module address, name, size, the
object file name (if known), and whether the module was compiled with
CONFIG_KALLSYMS.
The arguments are concerned with with the loading or deleting of symbolic
and debugging data from a module's object file. A modules's object file
always contains symbolic data (symbol names and addresses), but contains
debugging data only if the module was compiled with the -g CFLAG. In
addition, the module may have compiled with CONFIG_KALLSYMS, which means
that the module's symbolic data will have been loaded into the kernel's
address space when it was installed. If the module was not compiled with
CONFIG_KALLSYMS, then only the module's exported symbols will be loaded
into the kernel's address space. Therefore, for the purpose of this
command, it should noted that a kernel module may have been compiled in
one of following manners:
1. If the module was built without CONFIG_KALLSYMS and without the -g CFLAG,
then the loading of the module's additional non-exported symbols can
be accomplished with this command.
2. If the module was built with CONFIG_KALLSYMS, but without the -g CFLAG,
then there is no benefit in loading the symbols from the module object
file, because all of the module's symbols will have been loaded into the
kernel's address space when it was installed.
3. If the module was built with CONFIG_KALLSYMS and with the the -g CFLAG,
then the loading of the module's debugging data can be accomplished
with this command.
4. If the module was built without CONFIG_KALLSYMS but with the -g CFLAG,
then the loading of the both module's symbolic and debugging data can
be accomplished with this command.
-s module [objfile] Loads symbolic and debugging data from the object file
for the module specified. If no objfile argument is
appended, a search will be made for an object file
consisting of the module name with a .o or .ko suffix,
starting at the /lib/modules/<release> directory on
the host system. If an objfile argument is appended,
then that file will be used.
-d module Deletes the symbolic and debugging data of the module
specified.
-S [directory] Load symbolic and debugging data from the object file
for all loaded modules. For each module, a search
will be made for an object file consisting of the
module name with a .o or.ko suffix, starting at the
/lib/modules/<release> directory of the host system.
If a directory argument is appended, then the search
will be restricted to that directory.
-D Deletes the symbolic and debugging data of all modules.
-r Reinitialize module data. All currently-loaded symbolic
and debugging data will be deleted, and the installed
module list will be updated (live system only).
-o Load module symbols with old mechanism.
After symbolic and debugging data have been loaded, backtraces and text
disassembly will be displayed appropriately. Depending upon the processor
architecture, data may also printed symbolically with the "p" command;
at a minimum, the "rd" command may be used with module data symbols.
If crash can recognize that the set of modules has changed while running a
session on a live kernel, the module data will be reinitialized the next
time this command is run; the -r option forces the reinitialization.
EXAMPLES
Display the currently-installed modules:
crash> mod
MODULE NAME SIZE OBJECT FILE
c8019000 soundcore 2788 (not loaded)
c801b000 soundlow 336 (not loaded)
c801d000 sound 59864 (not loaded)
c802d000 ad1848 15728 (not loaded)
c8032000 uart401 6000 (not loaded)
c8035000 cs4232 2472 (not loaded)
c8043000 opl3 11048 (not loaded)
c8047000 3c59x 18152 (not loaded)
c804d000 sunrpc 53796 (not loaded)
c805c000 lockd 31528 (not loaded)
c8065000 nfsd 151896 (not loaded)
c8092000 nfs 29752 (not loaded)
Display the currently-installed modules on a system where all modules were
compiled with CONFIG_KALLSYMS:
crash> mod
MODULE NAME SIZE OBJECT FILE
e080d000 jbd 57016 (not loaded) [CONFIG_KALLSYMS]
e081e000 ext3 92360 (not loaded) [CONFIG_KALLSYMS]
e0838000 usbcore 83168 (not loaded) [CONFIG_KALLSYMS]
e0850000 usb-uhci 27532 (not loaded) [CONFIG_KALLSYMS]
e085a000 ehci-hcd 20904 (not loaded) [CONFIG_KALLSYMS]
e0865000 input 6208 (not loaded) [CONFIG_KALLSYMS]
e086a000 hid 22404 (not loaded) [CONFIG_KALLSYMS]
e0873000 mousedev 5688 (not loaded) [CONFIG_KALLSYMS]
e0878000 keybdev 2976 (not loaded) [CONFIG_KALLSYMS]
e08fd000 cdrom 34144 (not loaded) [CONFIG_KALLSYMS]
e0909000 ide-cd 35776 (not loaded) [CONFIG_KALLSYMS]
e0915000 scsi_mod 117928 (not loaded) [CONFIG_KALLSYMS]
e0935000 ide-scsi 12752 (not loaded) [CONFIG_KALLSYMS]
e093c000 microcode 5248 (not loaded) [CONFIG_KALLSYMS]
e0943000 sr_mod 18136 (not loaded) [CONFIG_KALLSYMS]
e0956000 floppy 59056 (not loaded) [CONFIG_KALLSYMS]
e0966000 sg 38060 (not loaded) [CONFIG_KALLSYMS]
e0971000 ip_tables 16544 (not loaded) [CONFIG_KALLSYMS]
e097d000 iptable_filter 2412 (not loaded) [CONFIG_KALLSYMS]
e097f000 e1000 76096 (not loaded) [CONFIG_KALLSYMS]
e09ba000 autofs 13780 (not loaded) [CONFIG_KALLSYMS]
e09c1000 parport 39072 (not loaded) [CONFIG_KALLSYMS]
e09ce000 lp 9220 (not loaded) [CONFIG_KALLSYMS]
e09d4000 parport_pc 19204 (not loaded) [CONFIG_KALLSYMS]
e09e2000 agpgart 59128 (not loaded) [CONFIG_KALLSYMS]
e0a1a000 radeon 117156 (not loaded) [CONFIG_KALLSYMS]
e2dc7000 sunrpc 91996 (not loaded) [CONFIG_KALLSYMS]
e2de1000 lockd 60624 (not loaded) [CONFIG_KALLSYMS]
e2df3000 nfs 96880 (not loaded) [CONFIG_KALLSYMS]
Load the symbolic and debugging data of all modules:
crash> mod -S
MODULE NAME SIZE OBJECT FILE
c8019000 soundcore 2788 /lib/modules/2.2.5-15/misc/soundcore.o
c801b000 soundlow 336 /lib/modules/2.2.5-15/misc/soundlow.o
c801d000 sound 59864 /lib/modules/2.2.5-15/misc/sound.o
c802d000 ad1848 15728 /lib/modules/2.2.5-15/misc/ad1848.o
c8032000 uart401 6000 /lib/modules/2.2.5-15/misc/uart401.o
c8035000 cs4232 2472 /lib/modules/2.2.5-15/misc/cs4232.o
c8043000 opl3 11048 /lib/modules/2.2.5-15/misc/opl3.o
c8047000 3c59x 18152 /lib/modules/2.2.5-15/net/3c59x.o
c804d000 sunrpc 53796 /lib/modules/2.2.5-15/misc/sunrpc.o
c805c000 lockd 31528 /lib/modules/2.2.5-15/fs/lockd.o
c8065000 nfsd 151896 /lib/modules/2.2.5-15/fs/nfsd.o
c8092000 nfs 29752 /lib/modules/2.2.5-15/fs/nfs.o
Load the symbolic and debugging data of the soundcore module from its
known location:
crash> mod -s soundcore
MODULE NAME SIZE OBJECT FILE
c8019000 soundcore 2788 /lib/modules/2.2.5-15/misc/soundcore.o
Delete the current symbolic and debugging data of the soundcore module,
and then re-load it from a specified object file:
crash> mod -d soundcore
crash> mod -s soundcore /tmp/soundcore.o
MODULE NAME SIZE OBJECT FILE
c8019000 soundcore 2788 /tmp/soundcore.o
After installing a new kernel module on a live system, reinitialize the
installed module list:
crash> !insmod mdacon
crash> mod
mod: NOTE: modules have changed on this system -- reinitializing
MODULE NAME SIZE OBJECT FILE
c8019000 soundcore 2788 (not loaded)
c801b000 soundlow 336 (not loaded)
c801d000 sound 59864 (not loaded)
c802d000 ad1848 15728 (not loaded)
c8032000 uart401 6000 (not loaded)
c8035000 cs4232 2472 (not loaded)
c8043000 opl3 11048 (not loaded)
c8047000 3c59x 18152 (not loaded)
c804d000 sunrpc 53796 (not loaded)
c805c000 lockd 31528 (not loaded)
c8065000 nfs 29752 (not loaded)
c806e000 autofs 9316 (not loaded)
c8072000 nfsd 151896 (not loaded)
c80a1000 mdacon 3556 (not loaded)
|
