During the last merge window (3.12) a couple of modules gained devname
aliases, but without the necessary major and minor information. These were
then silently ignored when generating modules.devname.
Complain loudly to avoid such errors sneaking in undetected in the future:
depmod: ERROR: Module 'zram' has devname (zram) but lacks major and minor information. Ignoring.
depmod: ERROR: Module 'uhid' has devname (uhid) but lacks major and minor information. Ignoring.
Cc: Kay Sievers <kay@vrfy.org>
Cc: Lucas De Marchi <lucas.demarchi@profusion.mobi>
With readdir_r() we should be providing enough space to store the dir
name. This could be accomplished by define an union like systemd does:
union dirent_storage {
struct dirent de;
uint8_t storage[offsetof(struct dirent, d_name) +
((NAME_MAX + 1 + sizeof(long)) & ~(sizeof(long) - 1))];
};
However in all places that we use readdir_r() we have no concerns about
reentrance nor we have problems with threads. Thus use the simpler
readdir() instead.
We also remove the error logging here (that could be added back by
checking errno), but it was not adding much value so it's gone.
It occurred to an openSUSE user that our mkinitrd would throw a
warning when used with kmod:
libkmod: conf_files_list: unsupported file mode /dev/null: 0x21b6
Grepping for the error message revealed that there might be a missing
"else" keyword here, since it is unusual to put an "if" directly after
closing brace.
In containers/VM's/initrd one might not have installed any modules and
accompanying modules.devname Don't fail if this is the case, just warn.
When used in systemd this means we don't get a failing unit on booting
containers.
The reason to have a kmod-nolib binary is that we need to call kmod on
test cases (or a symlink to it) and for testing things in tree. Since
we are using libtool if we are dinamically linking to libkmod what we
end up having is a shell script that (depending on the version *)
changes argv[0] to contain an "lt-" prefix. Since this screws with our
compat stuff, we had a kmod-nolib that links statically.
This all workaround works fine iff we are using one of the compat
commands, i.e. we are using the symlinks insmod, rmmod, modprobe, etc.
However if we are actually trying the kmod binary, this doesn't work
because we can't create a kmod symlink since there's already a kmod
binary.
So, completely give up on libtool fixing their mess. Now we create a
tool/test/ directory and the symlinks and kmod is put there.
* http://lists.gnu.org/archive/html/bug-libtool/2011-12/msg00023.html
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).
Lucas De Marchi
Tom Gundersen
Jan Engelhardt
Johannes Berg
Lucas De Marchi
Josh Boyer
Lucas De Marchi
Andrey Mazo
Aleksey Makarov