I have a loadable module that is throwing a warning about phys_mem_access_prot when built under Ubuntu 9.10 (Linux 2.6.31-22-server).
[664] make -C /lib/modules/`uname -r`/build M=`pwd`
make: Entering directory `/usr/src/linux-headers-2.6.31-22-server'
LD /home/chuck/dev/svd/built-in.o
CC [M] /home/chuck/dev/svd/svd.o
LD [M] /home/chuck/dev/svd/svd_drv.o
Building modules, stage 2.
MODPOST 1 modules
WARNING: "phys_mem_access_prot" [/home/chuck/dev/svd/svd_drv.ko] undefined!
CC /home/chuck/dev/svd/svd_drv.mod.o
LD [M] /home/chuck/dev/svd/svd_drv.ko
make: Leaving directory `/usr/src/linux-headers-2.6.31-22-server'
The function does show up in the System.map-2.6.31-22-server file
[667] grep phys_mem_access_prot /boot/System.map-2.6.31-22-server
ffffffff8103fb40 T phys_mem_access_prot
ffffffff8103fb50 T phys_mem_access_prot_allowed
and the driver loads, so I'm confused as to why modpost is unhappy. Is this a problem because the kernel doesn't export the function with EXPORT_SYMBOL()?
You've answered you own question! Any kernel function used by a module needs to be exported by one of the various EXPORT_SYMBOL() macros.
You'll also see problems if non-GPL modules need to use functions exported by EXPORT_SYMBOL_GPL.
Related
I'm trying to make a profile in Volatility 2. I tried on Debian, Kali and Ubuntu 120.04 and Ubuntu 18 (gcc 7.5.0). I tried to update the headers, export pathes etc.. but still I have the same error . I tried also to dowload a profile from github but they are too old ( i didn't found nothing new - just Ubuntu 14) . I also checked module.h info but didn't find antything helpfull. Any idea what i can do?
make -C //lib/modules/4.15.0-162-generic/build CONFIG_DEBUG_INFO=y M="/root/volatility-master/tools/linux" modules
make[1]: Entering directory '/usr/src/linux-headers-4.15.0-162-generic'
CC [M] /root/volatility-master/tools/linux/module.o
Building modules, stage 2.
MODPOST 1 modules
WARNING: modpost: missing MODULE_LICENSE() in /root/volatility-master/tools/linux/module.o
see include/linux/module.h for more information
CC /root/volatility-master/tools/linux/module.mod.o
LD [M] /root/volatility-master/tools/linux/module.ko
make[1]: Leaving directory '/usr/src/linux-headers-4.15.0-162-generic'
dwarfdump -di module.ko > module.dwarf
make -C //lib/modules/4.15.0-162-generic/build M="/root/volatility-master/tools/linux" clean
make[1]: Entering directory '/usr/src/linux-headers-4.15.0-162-generic'
CLEAN /root/volatility-master/tools/linux/.tmp_versions
CLEAN /root/volatility-master/tools/linux/Module.symvers
make[1]: Leaving directory '/usr/src/linux-headers-4.15.0-162-generic'
GOAL: compile samples/bpf, compile bpf/bpftool and use them.
PROBLEM: on a VM with Ubuntu 18.04 bionic with a kernel 4.18.0-25-generic I've installed kernel src code executing apt install linux-source-4.18.0.
Now I cd into /usr/src/linux-source-4.18.0/linux-source-4.18.0/samples/bpf and I run make and the result is
make -C ../../ /usr/src/linux-source-4.18.0/linux-source-4.18.0/samples/bpf/ BPF_SAMPLES_PATH=/usr/src/linux-source-4.18.0/linux-source-4.18.0/samples/bpf
make[1]: Entering directory '/usr/src/linux-source-4.18.0/linux-source-4.18.0'
scripts/kconfig/conf --syncconfig Kconfig
***
*** Configuration file ".config" not found!
***
*** Please run some configurator (e.g. "make oldconfig" or
*** "make menuconfig" or "make xconfig").
***
scripts/kconfig/Makefile:40: recipe for target 'syncconfig' failed
make[3]: *** [syncconfig] Error 1
Makefile:562: recipe for target 'syncconfig' failed
make[2]: *** [syncconfig] Error 2
make[1]: *** No rule to make target 'include/config/auto.conf', needed by 'include/config/kernel.release'. Stop.
make[1]: Leaving directory '/usr/src/linux-source-4.18.0/linux-source-4.18.0'
Makefile:203: recipe for target 'all' failed
make: *** [all] Error 2
If I cd into ../samples/bpf and I run sudo make the result is
Auto-detecting system features:
... libbfd: [ OFF ]
... disassembler-four-args: [ OFF ]
CC map_perf_ring.o
CC xlated_dumper.o
CC perf.o
CC cfg.o
CC common.o
CC cgroup.o
CC main.o
main.c:36:10: fatal error: bfd.h: No such file or directory
#include <bfd.h>
^~~~~~~
compilation terminated.
Makefile:92: recipe for target 'main.o' failed
make: *** [main.o] Error 1
QUESTIONS: what am I missing? After I compile them if I want to write a program which, for example, needs to use bpftool I have to write the program inside the source kernel directory or I can write it everywhere?
Build errors
The first case (Makefile:562: recipe for target 'syncconfig' failed) fails because you run make from the top of the linux kernel repository, and before trying to compile the samples, the build system tries to load a config file to use for your system (but does not find one).
Before trying to build the samples (make -C samples/bpf), you can create a .config file from your current kernel configuration like this:
$ cp /usr/src/linux-headers-$(uname -r)/.config <path to repo>/.config
$ make olddefconfig
Or even simply generate a default config file from scratch:
$ make defconfig
See make help from top directory to see the available make options.
Your second error, regarding bfd.h not found, is that you miss a library. Libbfd on Ubuntu comes with binutils-dev, so apt install binutils-dev should do the trick.
Compiling the programs
Finally, regarding your question on compiling the programs:
You can write and build program from the kernel repository, just by creating a new sample and reusing the existing Makefiles.
You can also write and compile programs outside of the kernel tree. The basic clang (v4.0 or above, if possible v6.0 or above) command to compile them usually looks something like this:
$ clang -O2 -emit-llvm -c my_bpf_prog.c -o - | \
llc -march=bpf -filetype=obj -o my_bpf_prog.o
You can find examples of programs compiled out of the kernel tree in that repository (disclaimer: by my company) or in the XDP tutorial repo.
I'm trying to install caffe, using CMake, but when I run make all (after running cmake .. from a build directory) I get the following error:
me#gimli:~/Downloads/caffe/build$ make all
[ 1%] Built target caffeproto
[ 1%] Linking CXX shared library ../../lib/libcaffe.so
/usr/bin/x86_64-linux-gnu-ld: /usr/local/lib/libleveldb.a(db_impl.cc.o): relocation R_X86_64_PC32 against symbol `_ZN7leveldb10EnvWrapper8ScheduleEPFvPvES1_' can not be used when making a shared object; recompile with -fPIC
/usr/bin/x86_64-linux-gnu-ld: final link failed: Bad value
collect2: error: ld returned 1 exit status
src/caffe/CMakeFiles/caffe.dir/build.make:40060: recipe for target 'lib/libcaffe.so.1.0.0' failed
make[2]: *** [lib/libcaffe.so.1.0.0] Error 1
CMakeFiles/Makefile2:267: recipe for target 'src/caffe/CMakeFiles/caffe.dir/all' failed
make[1]: *** [src/caffe/CMakeFiles/caffe.dir/all] Error 2
Makefile:129: recipe for target 'all' failed
make: *** [all] Error 2
I don't really understand CMake, but gather that somewhere I'm supposed to add -fPIC to a gcc command. But, I have no idea where I should make this change, or if there's somewhere in Cmake where I should tell it to construct the gcc command correctly.
How can I force CMake to create/use a gcc command with the -fPIC option, or is there something else entirely I should be doing?
The error is not from CMake but from the linker. It actually tells, that:
You cannot build shared library libcaffe.so with PIC (Position independent code) feature and link it with the static library libleveldb.a compiled without this feature.
Possible solutions are:
Get shared version of the static library (libleveldb.a in your case), so it will be compiled with PIC. This is what the error message suggests you.
Instead of building shared library (Caffe in your case), build static one, without using of PIC. Note, that in this case your will face with similar issues when trying to use resulted library in the future shared libraries.
For most CMake projects forcing the building static libraries can be performed with:
cmake -DBUILD_SHARED_LIBS=OFF <other parameters>
Strictly speaking, PIC feature is independent from the type (shared or static) of a library. So you may have a static library with PIC, or build a shared library without it.
For many CMake projects you may control PIC feature of the created libraries with
cmake -DPOSITION_INDEPENDENT_CODE=<ON|OFF> <other parameter>
I 'm trying to cross-compile rtl8192cu Driver in my Linux x86 machine for an ARM machine. I downloaded driver from Realtek website. Compilation guide refers editing Makefile as follows:
Ensure that the $PATH variable includes the location of the toolchain that you will be using to cross-compile the module. Refer to the setup instructions for the location of this directory.
Set the KSRC environment variable is set to the location of your Beagleboard's kernel source (see cross-compilation environment setup instructions for this directory path).
Set the KVER environment variable to your beagleboard's kernel version.
For this reson, I edited:
KVER := 2.6.32 (2.6.32. is BB's kernel version)
KSRC ?= /home/demetres/linux-2.6.32.61 (compiled kernel sources, taken from BB, stored on home/demetres/linux-2.6.32.61 location)
My question is:
What do I have to edit on Makefile's field CROSS_COMPILE:? I edited the path /home/demetres/CodeSourcery/Sourcery_CodeBench_Lite_for_ARM_GNU_Linux/bin but
make fails with these errors:
make ARCH=arm CROSS_COMPILE=/home/demetres/CodeSourcery/Sourcery_CodeBench_Lite_for_ARM_GNU_Linux/bin -C /home/demetres/linux-2.6.32.61 M=/home/demetres/Downloads/rtl8188C_8192C_usb_linux_v4.0.2_9000.20130911 modules
make[1]: /home/demetres/CodeSourcery/Sourcery_CodeBench_Lite_for_ARM_GNU_Linux/bingcc: Command not found
make[1]: Entering directory `/home/demetres/linux-2.6.32.61'
CC [M] /home/demetres/Downloads/rtl8188C_8192C_usb_linux_v4.0.2_9000.20130911/core/rtw_cmd.o
/bin/sh: /home/demetres/CodeSourcery/Sourcery_CodeBench_Lite_for_ARM_GNU_Linux/bingcc: No such file or directory
make[2]: *** [/home/demetres/Downloads/rtl8188C_8192C_usb_linux_v4.0.2_9000.20130911/core/rtw_cmd.o] Error 1
make[1]: *** [_module_/home/demetres/Downloads/rtl8188C_8192C_usb_linux_v4.0.2_9000.20130911] Error 2
make[1]: Leaving directory `/home/demetres/linux-2.6.32.61'
make: *** [modules] Error 2
INFO: Cross-toolchain on x86 machine is from CodeSourcery. I cross-compiled a helloworld.c for BB, by running arm-none-linux-gnueabi-gcc helloworld.c –o helloworld, on CodeSourcery/Sourcery_CodeBench_Lite_for_ARM_GNU_Linux/bin location.
_CodeBench_Lite_for_ARM_GNU_Linux/bingcc: Command not found
This error is due to you are not passing correct parameter
pass arm-none-linux-gnueabi-
where ever it finds {CROSS_COMPILE}gcc {CROSS_COMPILE}ld ...etc
this will be replaced with arm-none-linux-gnueabi-gcc arm-none-linux-gnueabi-ld
Edit
make ARCH=arm CROSS_COMPILE=/home/demetres/CodeSourcery/Sourcery_CodeBench_Lite_for_ARM_GNU_Linux/bin/arm-none-linux-gnueabi- -C /home/demetres/linux-2.6.32.61 M=/home/demetres/Downloads/rtl8188C_8192C_usb_linux_v4.0.2_9000.20130911 modules
If your cross-toolchain exported then try this
make ARCH=arm CROSS_COMPILE=arm-none-linux-gnueabi- -C /home/demetres/linux-2.6.32.61 M=/home/demetres/Downloads/rtl8188C_8192C_usb_linux_v4.0.2_9000.20130911 modules
I am trying to build from the bigloo scheme's latest source 3.8a on a Linux Mint 12 (lisa), which is Ubuntu 11 (Oneric) derivative:
Here is my "configure":
./configure --enable-pthread --enable-fthread --enable-ssl --enable-sqlite --enable-web --enable-multimedia --enable-mail --enable-calendar --enable-pkgcomp --enable-pkglib --enable-gstreamer --enable-text --enable-srfi1 --enable-srfi27 --enable-crypto --enable-openpgp --enable-phone --enable-alsa --enable-mpg123 --enable-csv --jvm=yes
** Configuration summary **
Release features:
release number.............. 3.8a
supported backends.......... native:yes JVM:yes
default backend............. native
additional APIs............. pthread fthread sqlite web multimedia mail calendar pkgcomp pkglib text srfi1 srfi27 packrat crypto openpgp phone mpg123 csv
native threads support...... yes
openssl support............. no
sqlite support.............. sqltiny + sqlite
dynamic libraries support... yes
Bee configuration:
bee support................. partial
emacs....................... emacs
emacs brand................. emacs23
Implementation details:
tuning...................... standard
cc.......................... gcc
gc.......................... custom (bigloogc-3.8a, v731)
Java version................ 1.3
bignum support.............. gmp (5.0.1)
Directories where Bigloo will be installed:
binaries.................... /usr/local/bin
libraries................... /usr/local/lib
files directory............. bigloo/3.8a
standard zip................ /usr/local/lib/bigloo/3.8a
standard dll................ /usr/local/lib/bigloo/3.8a
manual pages................ /usr/local/man/man1
info documentation.......... /usr/local/info
lisp files..................
temporary build dir......... /tmp
The "make" succeeds; however "make test" fails for pthread
*** pthread **********
make[2]: Entering directory `/home/liew/Downloads/bigloo3.8a/api/pthread/recette'
/home/liew/Downloads/bigloo3.8a/bin/bigloo -c -call/cc -O3 -fcfa-arithmetic -q recette.scm -o recette.o
/home/liew/Downloads/bigloo3.8a/bin/bigloo -O3 -fcfa-arithmetic -q recette.o -o recette
/usr/bin/ld: recette: hidden symbol `pthread_atfork' in /usr/lib/i386-linux-gnu/libpthread_nonshared.a(pthread_atfork.oS) is referenced by DSO
/usr/bin/ld: final link failed: Bad value
collect2: ld returned 1 exit status
make[2]: *** [recette] Error 1
make[2]: Leaving directory `/home/liew/Downloads/bigloo3.8a/api/pthread/recette'
make[1]: *** [c-test] Error 1
make[1]: Leaving directory `/home/liew/Downloads/bigloo3.8a'
make: *** [test] Error 2
According to this excellent post about this pthread issue, we need to rearrange the command line parameters while linking pthread library. However, I was unable to find the required Makefile code - probably because it relies on the Makefile default that links the library in a certain way.
Any help will be appreciated.
The problem is probably fixed in newer versions of bigloo.