Older systems may not have the be32toh function defined. Check for this
and fall back to checking the endianness and calling bswap_32 directly
if needed. This works on both old and new systems.
[Thomas De Schampheleire <thomas.de.schampheleire@gmail.com>:
address comments raised by Lucas De Marchi [1], update commit message]
[1] http://www.spinics.net/lists/linux-modules/msg01129.html
Add assert_return to use in testcases instead of assert. The issues
with assert are:
1) It's disabled when NDEBUG is defined
2) Even if it's well supported by testsuite (the parent will
report the child died) it can't output any meaningful
error message
If a test has expected_fail=true, it means the return code must be
different from 0 *and* the outputs must match. This way it's possible to
check if the error messages are printed as they should.
Since now depmod fails when there are module loops, let's at least give
better error messages, printing the loops we found. Since we may have
more than 1 loop, just printing the modules that are in loop is not
very clear.
Assuming as an example 2 independent loops, this is how the new messages
compare to the old ones:
Before:
depmod: ERROR: Found 5 modules in dependency cycles!
depmod: ERROR: /tmp/test-kmod//lib/modules/3.14.4-1-ARCH/kernel/moduleE.ko in dependency cycle!
depmod: ERROR: /tmp/test-kmod//lib/modules/3.14.4-1-ARCH/kernel/moduleB.ko in dependency cycle!
depmod: ERROR: /tmp/test-kmod//lib/modules/3.14.4-1-ARCH/kernel/moduleC.ko in dependency cycle!
depmod: ERROR: /tmp/test-kmod//lib/modules/3.14.4-1-ARCH/kernel/moduleD.ko in dependency cycle!
depmod: ERROR: /tmp/test-kmod//lib/modules/3.14.4-1-ARCH/kernel/moduleA.ko in dependency cycle!
After:
depmod: ERROR: Found 5 modules in dependency cycles!
depmod: ERROR: Cycle detected: moduleE -> moduleD -> moduleE
depmod: ERROR: Cycle detected: moduleB -> moduleC -> moduleA -> moduleB
In mod->modnamelen we were actually including the '\0', i.e.
strlen(modname) + 1. So rename it to modnamesz and add a comment in
depmod_module_is_higher_priority() to notice why it's correct since the
new one is really using strlen(modname).
If a value is added to the hash under a key that already exists the new value
replaces the old value for that key. Since key can be a pointer to data that
is part of value and freed by hash->free_value(), the key must be also
replaced and not only the value. Otherwise key potentially points to freed data.
Since the beginning depmod just warned about dependency loops and upon
creation of modules.dep{,.bin} it skipped the modules that were part of
a loop. However just skipping the modules may come as a surprise to
kernel module developers: they will need to try to load the module (or
to pay attention to the log messages) to notice thavt the module has not
been put in the index. Also, differently from module-init-tools we were
not skipping modules that depend on modules with dependency loops,
leading to a segfault in depmod.
So this is a summary of the change in behavior with this patch:
Loop 1)
A -> B -> C -
^ |
'------------
Before:
depmod: WARNING: found 3 modules in dependency cycles!
depmod: WARNING: /tmp/test-kmod/lib/modules/3.14.2-1-ARCH/kernel/moduleB.ko in dependency cycle!
depmod: WARNING: /tmp/test-kmod/lib/modules/3.14.2-1-ARCH/kernel/moduleC.ko in dependency cycle!
depmod: WARNING: /tmp/test-kmod/lib/modules/3.14.2-1-ARCH/kernel/moduleA.ko in dependency cycle!
return code: 0
After:
depmod: ERROR: Found 3 modules in dependency cycles!
depmod: ERROR: /tmp/test-kmod/lib/modules/3.14.2-1-ARCH/kernel/moduleB.ko in dependency cycle!
depmod: ERROR: /tmp/test-kmod/lib/modules/3.14.2-1-ARCH/kernel/moduleC.ko in dependency cycle!
depmod: ERROR: /tmp/test-kmod/lib/modules/3.14.2-1-ARCH/kernel/moduleA.ko in dependency cycle!
return code: 2
Loop 2)
A -> B -> C -
^ |
'-------
Before:
depmod: WARNING: found 2 modules in dependency cycles!
depmod: WARNING: /tmp/test-kmod//lib/modules/3.14.2-1-ARCH/kernel/moduleB.ko in dependency cycle!
depmod: WARNING: /tmp/test-kmod//lib/modules/3.14.2-1-ARCH/kernel/moduleC.ko in dependency cycle!
Segmentation fault (core dumped)
After:
depmod: ERROR: Found 2 modules in dependency cycles!
depmod: ERROR: /tmp/test-kmod/lib/modules/3.14.2-1-ARCH/kernel/moduleB.ko in dependency cycle!
depmod: ERROR: /tmp/test-kmod/lib/modules/3.14.2-1-ARCH/kernel/moduleC.ko in dependency cycle!
return code: 2
The segfault above could be fixed, but let's just fail everything
because dependency cycles should be fixed in the modules rather than
just be skipped in the index.
This partially reverts ad7f175 ("Add test for depmod using search dirs
with same prefix"). Testing it twice in the inverted order doesn't
ensure we get the bug with wrong ordering.
As put by Anssi Hannula <anssi@mageia.org>:
So the bug is triggered only if the shorter name is higher-prio _and_
shorter name is traversed first. If the long name is traversed first,
the bug don't trigger with either "search" directive order (and on my
"make check" runs this is the case).
This information can be found in /lib/modules/`uname -r`/modules.softdep, and
has only recently been exported by the kernel.
Also remove the advice about copying modules.softdep to /lib/modules as it is
not clear how to do this correctly with several kernels installed with
potentially conflicting soft dependencies.
Before we had softdeps, the usual idiom was
install foo /sbin/modprobe bar; /sbin/modprobe --ignore-install foo
ignoring errors from the first modprobe invocation. This also matches
the behavior of module-init-tools' implementation of softdep.
Add --enable-python configure switch so we build the python bindings. We
also pass version.py through SED_PROCESS macro, so the version is kept
in sync with kmod.
Acked-by: Andy Grover <agrover@redhat.com>
Lucas De Marchi
Randy MacLeod
Marco d'Itri
Holger Obermaier
Cristian Rodríguez
Lukas Anzinger
Leandro Pereira
Joe Lawrence
Michal Marek
Tom Gundersen