The modprobe.d (5) documentation for the "install" command
states that you could specify
install fred /sbin/modprobe barney; /sbin/modprobe --ignore-install fred
This makes some sense, but then the loading of "barney" is
hidden from the user who did only "modprobe fred". Thus,
it seems it should be possible to be able to unload the
"fred" module with "modprobe -r fred" by configuring the
"barney" module to also be removed:
remove fred /sbin/rmmod barney fred
(or similar.)
Make this possible by not checking the refcount when an
unload command was configured.
Reported-by: David Spinadel <david.spinadel@intel.com>
Add __attribute__((format)) to log_filep() and _show() functions, fixing
the bugs they found in the source code.
For functions that receive va_list instead of being variadic functions
we put 0 in the last argument, so at least the string is checked and we
get warnings of -Wformat-nonliteral type. So, it's better than adding a
pragma here to shut up the warning.
This file is created by depmod even if there's no node. In this case it
will be empty.
Previously 'kmod static-nodes' was segfaulting due to passing in==NULL
to fgets.
Also show the error message with %m.
This tool reads modules.devname from the current kernel directory and outputs
the information. By default in a human-readable format, and optionally in
machine-readable formats.
For now only the tmpfiles.d(5) format is supported, but more could easily be
added in the future if there is a need.
This means nothing but kmod needs to reads the private files under
/lib/modules/. In particular systemd-udevd can stop reading modules.devname.
Tools that used to read /lib/modules/`uname -r`/modules.devname directly, can
now move to reading 'kmod static-nodes devname'.
Putting something like "alias psmouse deadbeef" is a hackish way to
blacklist a module. While I don't encourage doing so, let's not explode
if we fiund such config files.
A small difference from the behavior of module-init-tools: we exit with
0 instead of 1.
Currently modprobe -r will fail if a module is built in and report that it
is built in. rmmod calls the same function to determine state but doesn't
handle the KMOD_MODULE_BUILTIN return code. This leads to confusing errors
like this:
libkmod: kmod_module_get_holders: could not open '/sys/module/loop/holders': No such file or directory
Error: Module loop is in use
Fix this so that it actually reports the correct problem to the user.
When the prefix symbol is set, take it into account while adding symbols
from System.map file by skipping it before "__ksymtab_" comparison.
Also, prevent inserted fake symbols (like "__this_module") from being
wrongly truncated from beginning.
In depfile_up_to_date_dir() we need to check if name has a kmod
extension. "path" variable there will be the directory name, which
doesn't contain an extension.
Without this, "depmod -A" returns that the modules.dep is up to date,
even if it isn't.
In depmod_modules_search_file() it's pointless to compare the basename,
so pass only the name to be checked.
If we are replacing a lower priority module (due to its location), we
already created a kmod_module, but didn't open the file for reading its
symbols. This means mod->kmod won't be NULL, and this is just ok. Since
all the functions freeing stuff below the previous assert already takes
NULL into consideration, it's safe to just unref mod->kmod and let the
right thing happens.
We index modules in depmod by it's uncompressed relative path, not
relative path. We didn't notice this bug before since this function is
only triggered if we release a module to be replaced by one of higher
priority.
Also fix a leftover log message referring to relpath instead of
uncrelpath.
This also fixes a bug in "e6996c5 rmmod: route all messages to syslog if
told to" in which "+ verbose" was removed. Instead of letting verbose
add to kmod_get_log_priority(), let it be similar to the other programs
instead.
When user supplied --help/-h, program should output to stdout the usage,
not to stderr. It's the expected behavior, what the user asked for,
not something to log or an error.
When we are logging to stderr we are previously relying on libkmod
sending it to the default location in case we are not asked to log to
syslog. The problem is that modprobe may be used in scripts that don't
want to log to syslog (since they are not daemons, like scripts to
generate initrd) and then it's difficult to know where the message comes
from.
This patch treats only the messages coming from libkmod.
Once we read all we need from a module, unref it so any resource taken
by it (including the mmap to access the file in libkmod) will be
dropped. This drastically reduces the number of open file descriptors
and also the memory needed, with no performance penalties. Rather,
there's a small speedup of ~2.6%.
Running depmod in a laptop with 2973 modules and comparing the number of
open file descriptors for kmod-10, before and after the last patches to
depmod (caaf438cb6 and HEAD) we have:
Before: 2980 simultaneously open fds
After: 7 simultaneously open fds
kmod-10: 7 simultaneously open fds
So now we have the speedup of caching the file in kmod_module without
the drawback of increasing the number of open file descriptors.
In depmod_module_add() we already called kmod_module_get_name() and
copied the string to our struct. Use it instead of calling again and
again the libkmod function.
The overall goal is to coalesce the accesses to a file that is the
backend of a module. This commit addresses the calls to
kmod_module_get_get_dependency_symbols(). Calling it earlier, while we
are iterating the modules allows us to free the struct kmod of each
module much sooner. We are still not freeing it since there are other
places that must be refactored first.
There's a performance penalty of ~2.5% from previous commit.
The overall goal is to coalesce the accesses to a file that is the
backend of a module. This commit addresses the calls to
kmod_module_get_info(). Calling it earlier, while we are iterating the
modules allows us to free the struct kmod of each module much sooner. We
are still not freeing it since there are other places that must be
refactored first.
A nice side effect is that this commit reduces in ~33% the calls to
malloc(), giving a speedup of ~6% for cold caches (reproduced on only 1
laptop).
We now index the modules by uncompressed-relative-path instead of
relative-path. This is because the file modules.order, coming from
kernel, always comes with uncompressed paths. This fixes the issue of
not sorting the aliases correctly due to paths not matching when using
compressed modules.
This is a broken option that only leads to misery and incompatabilities
with other systems. Kbuild doesn't come close to supporting directories
other than /lib/modules with several targets simply failing without
hacky fixes. Simply remove the option and all traces of it, as it
doesn't make sense in today's world.
This fixes a change in behavior regarding kmod and module-init-tools:
when trying to load a module by alias, we should check if it's
blacklisted, regardless of the command line arguments passed.
This was reported by "Dmitry V. Levin <ldv@altlinux.org>".
Only the public header maintains #ifndef in the header, together with
pragma. The other ones contain only pragma.
As reported by Shawn Landden on systemd mailing list this is compatible
with all major compilers and gcc has this since version 3.3.
Before:
=======
[lucas@vader kmod]$ sudo depmod
[lucas@vader kmod]$ echo $?
0
[lucas@vader kmod]$ ls -l /lib/modules/$(uname -r)
total 12
drwxr-xr-x 8 root root 160 Jun 13 11:05 kernel
-rw-r--r-- 1 root root 12288 Jun 15 21:29 modules.alias
-rw-r--r-- 1 root root 0 Jun 15 21:29 modules.alias.bin
-rw-r--r-- 1 root root 0 Jun 15 21:29 modules.dep
-rw-r--r-- 1 root root 0 Jun 15 21:29 modules.dep.bin
-rw-r--r-- 1 root root 0 Jun 15 21:29 modules.devname
-rw-r--r-- 1 root root 0 Jun 15 21:29 modules.softdep
-rw-r--r-- 1 root root 0 Jun 15 21:29 modules.symbols
-rw-r--r-- 1 root root 0 Jun 15 21:29 modules.symbols.bin
Note that modules.alias is truncated and the other have size == 0
After:
======
[lucas@vader kmod]$ sudo ./tools/depmod
WARNING: could not open /lib/modules/3.5.0-rc2-demarchi-00028-g94fa83c/modules.order: No such file or directory
ERROR: Could not create index: output truncated: No space left on device
[lucas@vader kmod]$ echo $?
1
Previously, depmod would relegate failures of kmod_module_get_symbols()
to debug output, assuming the "error" was simply a lack of symbols.
Leave the ENOENT return to debug output, but report anything else as a
real error.
init_module returns -ENOENT when the module failed to load because of a
bad parameter or unknown symbol. Throw a more descriptive error message
than the generic "No such file or directory" to alert the user.
Fixes Debian bug 668216.
More or less confusing message, but if module is builtin in the live
system, it doesn't mean it's builtin in the target kernel.
Instead we now check if module has a path. It don't have a path only if
it's builtin in the target or if it doesn't exist at all. The latter
should not be a problem since this code is being called from inside the
library. Anyway, put an assert to make sure we get bug reports if any
case slipped in here.
We really haven't paid this code much attention, and it's somewhat
evident in our divergence in behavior from module-init-tools. This patch
asserts the following behavior on exit:
* modprobe -r realmod_notloaded => exit zero
* modprobe -r --first-time realmod_notloaded => exit non-zero
* modprobe -r bogusmod => exit non-zero
A simple case of breakage before this commit:
$ touch aes
$ modinfo aes
filename: /tmp/aes
ERROR: could not get modinfo from 'aes': Invalid argument
Add a new is_module_filename() function that attempts to do more than
just check if the passed argument is a regular file. We look at the name
for a '.ko' string, and if that is found, ensure it is either at the end
of the string or followed by another '.' (for .gz and .xz modules, for
instance). We don't make this second option conditional on the way the
tools are built with compression support; the file is a module file
regardless and should always be treated that way.
When doing this, and noticed in the test suite output, we open the
system modules index unconditionally, even if it is never going to be
used during the modinfo call, which is the case when passing module
filenames directly. For only one module there's not much advantage in
pre-loading the index, so just remove the call to kmod_load_resources().
With-help-from: Dave Reisner <dreisner@archlinux.org>
[lucas.demarchi@profusion.mobi: remove call to kmod_load_resources()]
Add kmod-* prefixed tool names, add 'tags' in root directory (for ctags,
matches cscope.out ignore already in there), and prefix tools/ entries
with '/' so they are absolute ignores and don't apply to subdirectories.
fopen() will not reset errno if it succeeds so we should
make sure that we only use errno in error cases.
Also fix the diagnostic messages to not use strerror
when there is no error since strerror will not return
anything useful in this case
Effectively catch and the zero and non-zero cases and error out
appropriately. Note that -EEXIST will only ever be returned when
KMOD_PROBE_STOP_ON_ALREADY_LOADED is set as a probe_insert_module flag.
Distro packagers should create them instead. It's too much trouble to
create them in the build system and every distro wants a different path
for them.
It was not on module-init-tools and it doesn't make much sense. It will
deal with dependencies, but looking at modules in the index. This might
not be the module we want if we are loading another from outside of the
tree.
Dealing with paths causes this bug (supposing there's a module names
squashfs):
# cd /
# touch squashfs
# modprobe squashfs
That is because it detects that squashfs exists as a file and it will
try to load it instead of the alias "squashfs".
If you need to load a module from a path, use insmod.
Thanks to Silvan Calarco <silvan.calarco@mambasoft.it> who reported the
bug and helped debugging it.
Index dump doesn't use stdio.h function and instead call write()
directly on STDOUT_FILENO file descriptor. Therefore we need to flush
stdio buffers before calling it, to be sure the configuration dump will
appear before index's.
Just like the module insertion, module removal is remade.
The dependencies line that comes from modules.dep already contains all
the dependencies necessary to remove that module. Therefore modprobe
doesn't have to do the recursion between the modules in order to remove
it. All we have to do is to remove in order:
For the module being removed:
----------------------------
1. softdeps (in reverse order)
2. deps (in reverse order)
3. module
4. postdeps (in reverse order)
For any of the dependencies:
----------------------------
1. softdeps (in reverse order)
2. module
3. softdeps (in reverse order)
The dependencies line that comes from modules.dep already contains all
the dependencies necessary to insert that module. Therefore modprobe
doesn't have to do the recursion between the modules in order to load a
module. All we have to do is to load in order:
For the module being loaded:
----------------------------
1. softdeps
2. deps
3. module
4. postdeps
For any of the dependencies:
----------------------------
1. softdeps
2. module
3. softdeps
Now with './tools/modprobe --show-depends ahci' (ahci is builtin) we have the following
output:
$ ./tools/modprobe --show-depends ahci
builtin ahci
Just like modprobe from m-i-t. Previously we had:
$ ./tools/modprobe --show-depends ahci
FATAL: Module ahci not found.
Deleting modules (we have found replacements) invalidates the indices
because the array collapses removed elements, hitting the assertion.
Since we don't make use of the array until the sorting step, build it from
the modules_by_name hash instead.
modprobe doesn't have support for handling dependency loop. That happens
with poorly written softdeps that can introduce a loop. We must deal
with them like it's being done in libkmod.
However, we can break a dependency loop when the dependency was already
inserted. This commit fixes this issue, that happens in the following
scenario:
dependencies:
-------------
modA:
modB: modA
modC: modA
config:
softdep modA post: modB modC
This creates the following loop:
modA
inserted ok
handle post-soft-deps of modA -> modB modC
modB
handle dependencies of modB -> modA
modA is already inserted
handle post-soft-deps of modA -> modB modC
And so on and so forth.
Now we break the loop by checking if module is already inserted, before
handling it. Thus this gives us:
modA
inserted ok
handle post-soft-deps of modA -> modB modC
modB
handle dependencies of modB -> modA
modA is already inserted
inserted ok
modC
handle dependencies of modC -> modA
modA is already inserted
inserted ok
In line with m-i-t's behavior, we should check to see if each module is:
- loaded
- has any holders
- has a 0 refcnt
Detecting any of these lets us provide a more useful message than the
kernel's EPERM response to delete_module(2).
Additionally, alter the main loop behavior to avoid exiting early on the
first error.
Symlinking tools to kmod doesn't work because argv[0] is not the name of
the symlink, but rather 'kmod' (since libtool's wrapper script calls the
tools/.libs/kmod directly)
Now we create another binary kmod-nolib that is statically linked to
libkmod so we can call the binary directly and do not worry about
LD_LIBRARY_PATH.
demarchi> scenario is the following:
demarchi> modA depends on modB and modC
demarchi> if there's a race when trying to insert a dependency of a module, say
modB, it will stop loading all the modules
demarchi> it should check by "module already loaded error"
demarchi> like it does for modA
Module aliases can be bigger than NAME_MAX. So, replace with PATH_MAX
that is bigger enough to hold them.
Technically in some places NAME_MAX would be sufficient (those using
module names only), but they use functions that can be called with
alias. So increase the buffers in these cases to PATH_MAX too.
We cannot create a kmod_module for existing module name, it will fail
due existing in the hash table "modules_by_name".
To avoid it, we first delete the existing module, if lower priority,
then add the new one.
kmod_module_new_from_path() is called only when the former module was
deleted or does not exist.
This code was never tested, my bad!
* the prefix should be ignored, as it is not stored in cfg_search/override.
* baselen should not include '/'.
* search length should not include '\0'.
* override path should not include cfg->dirname prefix.
note that the hash algorithm is different thus the output order will
be different as well.
to compare the outputs, sort the files:
depmod -n | grep '^alias symbol:' | sort > /tmp/orig
kmod-depmod -n | grep '^alias symbol:' | sort > /tmp/new
diff /tmp/orig /tmp/new
this is the initial code for depmod, it should:
* use configuration from /run/depmod.d, /etc/depmod.d, /lib/depmod.d
* respect overrides and searches
* resolve symbols and dependencies
* break circular dependencies (dependency loops)
* --errsyms: print out modules with unresolved symbols and incorrect crc
* --symbol-prefix: respect architecture symbol prefix
it will not:
* --quick: does not do quick mode
* --warn: does not warn on duplicates
* --filesyms: does not load symbols from map file
* --symvers: does not load symbol versions from map file
* dump files: does not dump any files at the moment.
it is highly untested, then I appreciate your help with real world
scenarios using overrides and searches. To get output run with -vvvvvv.
next version should fill in the gaps and at least generate the files
Johannes Berg
Lucas De Marchi
Tom Gundersen
Josh Boyer
Lucas De Marchi
Andrey Mazo
Aleksey Makarov
Dave Reisner
Elan Ruusamäe
Dan McGee
Khem Raj
Thierry Vignaud
Jan Alexander Steffens (heftig)
Gustavo Sverzut Barbieri
Rolf Eike Beer
Dave Reisner
Leandro Pereira