out of sheer curiosity I tried compiling a 2.6.0 kernel on my slackware machine.
root#darkstar:/home/linux-2.6.0# uname -a
Linux darkstar 2.6.37.6-smp #2 SMP Sat Apr 9 23:39:07 CDT 2011 i686 Intel(R) Core(TM)2 Duo CPU P8600 # 2.40GHz GenuineIntel GNU/Linux
When I try compiling I get :-
root#darkstar:/home/linux-2.6.0# make menuconfig
HOSTCC scripts/fixdep
scripts/fixdep.c: In function 'traps':
scripts/fixdep.c:359:2: warning: dereferencing type-punned pointer will break strict-aliasing rules
scripts/fixdep.c:361:4: warning: dereferencing type-punned pointer will break strict-aliasing rules
HOSTCC scripts/kconfig/conf.o
HOSTCC scripts/kconfig/mconf.o
scripts/kconfig/mconf.c:91:21: error: static declaration of 'current_menu' follows non-static declaration
scripts/kconfig/lkc.h:63:21: note: previous declaration of 'current_menu' was here
make[1]: *** [scripts/kconfig/mconf.o] Error 1
make: *** [menuconfig] Error 2
Some hints on what im doing wrong? Thanks!
How are you doing this to start with?
Typically, you download the latest kernel from kernel.org, copy the tarball to /usr/src, then:
1. tar -zxvvf linux-2.6.xxxx.tar.gz
2. ln -nsf linux-2.6.xxxx linux # ie: Update the "/usr/src/linux" symbolic link to
# point to the new kernel source directory
3. make menuconfig # or make xconfig
4. make modules # Build the kernel modules
5. make modules_install # Install the previously built modules for the
# new kernel
6. make bzImage # Create the boot image
At this point, DO NOT run make install. Most guides say to do this, but this is WRONG! Instead, copy the newly created bzImage file to /boot (ie: find -name bzImage /usr/src/linux, then cp to /boot), then edit your LILO configuration file (edit /etc/lilo.conf, and when done, run lilo), then reboot your system (ie: init 6 or shutdown -r now), and try out the new kernel.
The whole point of skipping the make install step is because it overwrites/replaces your existing kernel. The steps I described above allow you to have the new kernel and your existing kernel both installed and runnable in parallel. If the new kernel is broken or your left out an important option, you can still fall back to your existing stable/working kernel without the need for a boot/recovery CD/DVD.
If I recall well i think you are missing the ncurses libraries. Those are needed to create the interface with menuconfig.
Try a to do a make xconfig from an X session and see if it works.
if that is the case then the ncurses libs are definitely missing.
check with:
ls /var/log/packages/ncurses*
to see if installed
Related
I've been spending the last week trying to reach one objective that i still haven't reached.
My final goal would be to cross-compile for some architectures (in this question i will take as an example only one which is MIPSLE) a couple of kernel modules that i'd like to use on my home router, by loading them at runtime with INSMOD.
My router is missing of some iptables functionalities and that's why during the kernel compilation, who compiled it decided to get rid of them.
The current kernel version is quite obsolete: Linux version 2.6.36+ by doing /proc/version
I read a lot of documentations and still i'm not sure if it possible to compile just some modules or if it's necessary to compile the whole kernel everytime (some people said that for some modules is possible and for others with more dependencies is not, is that true ?).
In this case the kernel modules i need are located in /net/ipv4/netfilter/
Since i didn't get how to compile just kernel modules in a standalone way, i decided to cross-compile the entire kernel and take the modules i needed.
So i've downloaded the proper toolchain (uclibc mipsle toolchain) and i was successfull in compiling a simple working hello world that i've executed on my router where i have an ssh shell.
So i'm sure that the toolchain i'm using it's the correct one.
Now, since i wanted to test with a recent version of kernel i've downloaded the latest ubuntu 20 with correspective kernel and i've successfully compiled it and the kernel modules that i was speaking about before, were there inside the netfilter folder in .ko format , PERFECT !
I clearly used the /boot/config_file of my host machine as .config
So, after I've downloaded the exact same kernel version that my router has (2.6.36) and I've tried to compile it with a .config file that i've found on GitHub related to a mipsle device with my same kernel version.
Here i think we have the first problem, I tried to find the .config of my device in order to have a smooth configuration but i don't have the /boot folder and in also was not in /proc.
How can i get it?
Anyway, I've used it and the compilation didn't look like failed, but these are the last lines:
CC drivers/usb/storage/usual-tables.o
LD drivers/usb/storage/usb-storage.o
LD drivers/usb/storage/built-in.o
LD drivers/usb/built-in.o
LD drivers/video/built-in.o
LD drivers/built-in.o
LD vmlinux.o
MODPOST vmlinux.o
GEN .version
CHK include/generated/compile.h
UPD include/generated/compile.h
CC init/version.o
LD init/built-in.o
LD .tmp_vmlinux1
KSYM .tmp_kallsyms1.S
AS .tmp_kallsyms1.o
LD .tmp_vmlinux2
KSYM .tmp_kallsyms2.S
AS .tmp_kallsyms2.o
LD vmlinux
SYSMAP System.map
SYSMAP .tmp_System.map
OBJCOPY arch/mips/boot/vmlinux.bin
Building modules, stage 2.
MODPOST 1 modules
CC drivers/scsi/scsi_wait_scan.mod.o
LD [M] drivers/scsi/scsi_wait_scan.ko
It says "1 Modules" but I don't understand why and inside the /net/ipv4/netfilter folder now I have .o files instead of .ko like if they've not been linked.
Since i was getting mad and I didn't know what to try more after several attempts, I've decided to use the config file of my host machine (ubuntu 2020, kernel 5.4.0.26) and the compilation was successful, with .ko files inside the folder.
The problem was that obviously they were modules compiled for x86-64 instead of MIPS and other clear "problems" related to the configuration of my x86-64 machine.
So, what i think now is that the .config I've found could be broken somehow, I also tried to disable, by adding a comment, that SCSI module, but nothing, I always get the same stuff.
And obviously between each try I always did a make distclean and make clean.
What do you suggest me to do? I won't even post all the references i've read about this stuff because i could sigsegv StackOverflow's server with that amount of data.
Thanks to everyone and sorry for the wall-post.
i'm not sure if it possible to compile just some modules or if it's necessary to compile the whole kernel every time
Well, you can compile just single modules, but compiling a module requires the kernel to be already built. Once you do that one time though, you should be able to compile other modules singularly. That is, of course, if you do not wish to embed them in the kernel itself (CONFIG_XXX=y instead of CONFIG_XXX=m). You should be able to compile only the module you want like this (assuming /path/to/linux is the directory where your already built kernel source resides):
$ cd /path/to/linux
$ cd path/to/module/folder
$ make -C /path/to/linux M=$(pwd) modules
I tried to find the .config of my device in order to have a smooth configuration but i don't have the /boot folder and it also was not in /proc. How can i get it?
Where did you look precisely? The presence of /proc/config.gz depends on CONFIG_IKCONFIG_PROC (see also here). If you cannot find the file then it's most likely because that configuration option was disabled when the kernel was built. You may try look under /boot (as you already did), or under /lib/modules/$(uname -r)/build/.config, but unfortunately there's not much else to do otherwise.
I've seen people suggest trying to run modprobe configs and then check /proc/config.gz, but that seems strange since as far as I know the kernel config shouldn't be configurable to be available as a loadable module.
What do you suggest me to do?
Well, the most important thing you want right now is to find the configuration file for your router (or a compatible one). If you cannot find that, it will be pretty hard to get everything right. You might want to search for OpenWRT versions available for your router (if any), or really anywhere else on the internet as long as you can find a suitable configuration. Include your router brand and/or model in your searches. StackOverflow can't really help you that much about this though.
You can try cross-compiling a 5.4 kernel with default config plus the module you want. For example, assuming you have the right cross-compilation toolchain ready:
cd /path/to/linux
make ARCH=mips CROSS_COMPILE=your-cross-toolchain-prefix- defconfig
make ARCH=mips CROSS_COMPILE=your-cross-toolchain-prefix- menuconfig
# ... enable the module, tune the config ...
make -j ARCH=mips CROSS_COMPILE=your-cross-toolchain-prefix-
In any case, consider the fact that jumping from a 2.6 to a 5.4 kernel is a pretty big change, and it's likely to end up breaking everything, so be sure to make a backup of your router's firmware before trying anything.
I have a Makefile made by following this example:
cross compile kernel module
I built a 4.14 Linux kernel from an older Xilinx source, and then built a out-of-kernel module with that script, pointing it to the said 4.14 kernel sources, and filling in the blanks for my particular platform architecture.
That worked.
(It's based on this code, if that matters: dma-proxy.c)
Now I need a newer version, and got Xilinx sources with a kernel named 5.6.0-rc1.
(--branch "zynqmp-soc-for-v5.7" from here)
Building that kernel also worked fine.
If I now use a scrubbed clean directory (incl. hidden files) with my module source code and that Makefile again, pointing to the newer kernel sources, it does neither produce a .ko file nor an error message.
All I get is:
make ARCH=arm64 CROSS_COMPILE="aarch64-linux-gnu-" -C /home/sk/src/XILINX/linux-xlnx SUBDIRS=/home/sk/src/XILINX/dma-proxy/driver modules
make[1]: Entering directory '/home/sk/src/XILINX/linux-xlnx'
CALL scripts/checksyscalls.sh
CALL scripts/atomic/check-atomics.sh
MODPOST 28 modules
make[1]: Leaving directory '/home/sk/src/XILINX/linux-xlnx'
No .ko file in my folder as it was before when building with 4.14, and it doesn't list actually compiling anything.
I find it curious that it says "MODPOST 28 modules", whereas with pointing it to kernel 4.14, it expectedly says "1 modules"
Has anything changed between 4.14 and 5.x that would cause this?
Mkay, here is the suggested makefile template by the tutorial I referenced in the question:
PWD := $(shell pwd)
obj-m += hello.o
all:
make ARCH=arm CROSS_COMPILE=$(CROSS) -C $(KERNEL) SUBDIRS=$(PWD) modules
clean:
make -C $(KERNEL) SUBDIRS=$(PWD) clean
Turns out that if I replace SUBDIRS=$(PWD) with M=$(PWD), it works. Now if I google explicitly for that M variable in conjunction with building kernel modules, I do find text that show it that way. But the net is also littered with examples using SUBDIRS, and it worked for me with a fairly recent kernel (4.14).
Then I did find references hinting at this being an old way of doing it, like from here:
make -C $KDIR SUBDIRS=$PWD
Same as M=. The SUBDIRS= syntax is kept for backwards compatibility.
In fact, this seems to be really old, like, kernel 2.6.7 old. Unfortunately, fairly recent tutorials show the old way.
I am trying to "make" and load the "/drivers/md/raid0.ko" module into my linux kernel but I am getting this error.
# modprobe raid0 --force-vermagic
modprobe: ERROR: could not insert 'raid0': Exec format error
dmesg
[Dec 2 15:10] raid0: version magic '5.0.0 SMP mod_unload ' should be '5.0.0-36-generic SMP mod_unload '
My kernel version is
# uname -a
Linux ubuntu1 5.0.0-36-generic #39-Ubuntu SMP Tue Nov 12 09:46:06 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux
and the code from which I am trying to load is taken from the link https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/linux-5.0.tar.xz
Hence the version in that is 5.0.0, without the EXTRAVERSION -36
I have tried a number of things but failed.
Setting the EXTRAVERSION using command make EXTRAVERSION=-1 modules_prepare, before building the module
Using the --force-vermagic while loading the kernel, but it fails.
Copying the Makefile firectly from /usr/lib/modules/$(uname -r)/build/Makefile before building the kernel.
I have used both make SUBDIRS=drivers/md modules and make M=drivers/md for building, but same result for both.
Need help!
force modprobe to ignore the magic str
use --force-vermagic optin
Every module contains a small string containing important information,
such as the kernel and compiler versions. If a module fails to load
and the kernel complains that the "version magic" doesn't match, you
can use this option to remove it. Naturally, this check is there for
your protection, so this using option is dangerous. This applies to
any modules inserted: both the module (or alias) on the command line
and any modules on which it
in this case modprob ignore magic str
Some time ago, I developed a kernel module for ARMv7 (Cortex-A5). This module worked fine, but I needed to add a feature to it. Unfortunately, the machine that had the cross-compiler toolchain installed got repurposed in the mean time, so I had to set it up again. Of course, I found that I hadn't documented all the details, and I have been struggling to get a module that would actually load. After a day or so, I managed to compile something that was accepted by insmod on the target.
But the module does nothing.
insmod does not give me any errors. dmesg doesn't show anything, although the module is supposed to print some info from its probe routine. Also, the character device it's supposed to create does not exist, obviously the module's probe routine didn't run.
If I do modinfo on both the old .ko (which I still have) and new .ko, there are no differences. file also shows the same output, except for the sha1 checksum, which is to be expected:
module_old.ko: ELF 32-bit LSB relocatable, ARM, EABI5 version 1 (SYSV), BuildID[sha1]=1f55850e8da4b3b5931536060d62193d94730cf6, not stripped
module_new.ko: ELF 32-bit LSB relocatable, ARM, EABI5 version 1 (SYSV), BuildID[sha1]=c3b1f6fdcb72381beb7b8a766c70af7a1252a78f, not stripped
The only difference I see is that the new .ko is about 10x bigger than the old one:
-rw-r--r-- 1 root root 154504 Apr 21 23:38 module_new.ko
-rw-rw-r-- 1 root root 17956 Oct 4 2017 module_old.ko
My Makefile is as follows:
obj-m += mymodule.o
KERNEL_SOURCE_DIR = /home/ludo/linux-at91-linux4sam_5.3
all:
make -C $(KERNEL_SOURCE_DIR) CROSS_COMPILE=arm-linux-gnueabihf- ARCH=arm M=$(PWD) modules
clean:
make -C $(KERNEL_SOURCE_DIR) CROSS_COMPILE=arm-linux-gnueabihf- ARCH=arm M=$(PWD) clean
I tried adding
CFLAGS_mymodule.o := -march=armv7-a -mtune=cortex-a5
but this made no difference.
I'm building on Debian Jessie (8.10) with gcc 4.9. I do not recall exactly with what GCC version I built the old version, but it was 4.x, not newer.
Any ideas how I can debug this problem?
I forgot to document a very important step in the build process. Before building the module, one needs to ensure that the configuration is consistent. This can be done by executing, from the root of the kernel source tree:
make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- sama5_defconfig
make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- modules
Then the module can be compiled and all is good.
I am a newer in linux and using ubuntu(4.4.0-64-generic) in vmware fusion. I am learning how to compile kernel. So, I downloaded the kernel(linux-4.4.52.tar.xz) from the kernel.org. But when I input make menuconfig, there are some errors.
root#ubuntu:/usr/src/linux-4.4.52# make menuconfig
HOSTCC scripts/basic/fixdep
In file included from /usr/include/x86_64-linux-gnu/bits/posix1_lim.h:160:0,
from /usr/include/limits.h:143,
from /usr/lib/gcc/x86_64-linux-gnu/5/include-fixed/limits.h:168,
from /usr/lib/gcc/x86_64-linux-gnu/5/include-fixed/syslimits.h:7,
from /usr/lib/gcc/x86_64-linux-gnu/5/include-fixed/limits.h:34,
from scripts/basic/fixdep.c:114:
/usr/include/x86_64-linux-gnu/bits/local_lim.h:38:26: fatal error: linux/limits.h: No such file or directory
compilation terminated.
scripts/Makefile.host:91: recipe for target 'scripts/basic/fixdep' failed
make[1]: * [scripts/basic/fixdep] Error 1
Makefile:444: recipe for target 'scripts_basic' failed
make: * [scripts_basic] Error 2
I have installed headers files and done everything I can do. Someone can help me solve this problem?
You symbolic link is wrong; /usr/src/linux-4.4.0-64-generic/include/linux is the wrong directory and must not be linked to /usr/include/linux.
The kernel has two sets of headers: kernel-internal headers, and user API headers. The latter are inside the uapi directory, and they are what user-space program should see.
When you are compiling your own kernel, you can install the user-space headers of that kernel with make headers_install.
When you are using your distribution's kernel, you can just (re-)install the appropriate package (in your case, linux-headers-generic), and that will do the right thing as long as you do not muck around with those files afterwards.