So, I need to run this command:
vnstat -tr
But as a user I just created, not as root, as root it works fine, but as a regular user I get this:
Error: Unable to get interface "eth0" statistics.
Error: Interface "eth0" not available, exiting.
Operating system: Debian Linux 6.0.6
The problem was grsecurity locking /proc/net/dev from viewing it by users. The solution was to downgrade from ovhs linux core from 3.10.X to 3.8.13.
Related
I need to control some DC motors using PWM. I have been trying to use the bcm2835 library, but I need root access to run my program. I need to avoid this, as this program is part of a ROS package, which gives problems if run as root. I have tried to follow the instructions that appear in the section "Running as root", but I haven't been successful. I have done the following.
First, I have installed libcap2 and libcap-dev and added my user to the kmem group.
sudo apt-get install libcap2 libcap-dev
sudo adduser ubuntu kmem
Then, I have installed the version latest version of bcm2835 library.
wget http://www.airspayce.com/mikem/bcm2835/bcm2835-1.67.tar.gz
tar zxvf bcm2835-1.67.tar.gz
cd bcm2835-1.67
./configure
make
sudo make check
sudo make install
After that, I uncommented the #define BCM2835_HAVE_LIBCAP line in bcm2835.h, which I found in /usr/local/include/.
I allowed write access to /dev/mem by members of kmem group.
echo 'SUBSYSTEM=="mem", KERNEL=="mem", GROUP="kmem", MODE="0660"' | sudo tee /etc/udev/rules.d/98-mem.rules
sudo reboot
And finally, I compiled my program (called l298n) and run the following command.
sudo setcap cap_sys_rawio+ep l298n
After doing all this, my program is still not able to provide PWM control unless I run it as root.
Have I done anything wrong? Is there any other way around this? As far as I know, other libraries would run into the same problem, as it depends on the access level of /dev/mem.
I am running Ubuntu 20.04 LTS in a Raspberry Pi 3B+.
What you did wrong:
You edited the wrong bcm2835.h, you need to edit bcm2835.h where ever you unpacked bcm2835-1.67.tar.gz, not /usr/local/include.
You didn't recompile the library to actually have the added feature in it.
Also, if you're just accessing the GPIO pins and don't need non-root access to /dev/mem then there's no need to do anything more than adding access rights to /dev/gpiomem to your non-root user.
Have you tried version 68 already ?
There where made some changings concerning 'BCM2835_HAVE_LIBCAP'.
I have an out-of-tree Linux kernel module that I need to compile. When I execute "make" in the kernel module directory I am getting:
"fatal error: stdarg.h: No such file or directory"
Before starting the build I installed the header file based on my Linux distribution.
$sudo apt-get install kernel-headers-$(uname -r)
How can I solve this compilation error? (my distribution is Ubuntu 16.04 with linux-headers-4.15.0-42-generic)
I ran a search of stdarg.h with the "locate" command to see if I can sport the file on the system.
I got:
/usr/include/c++/5/tr1/stdarg.h
/usr/lib/gcc/i686-linux-gnu/5/include/cross-stdarg.h
/usr/lib/gcc/i686-linux-gnu/5/include/stdarg.h
...
It tells me there is at least one stdarg.h provided by the compiler.
I tried to include the path "/usr/lib/gcc/i686-linux-gnu/5/include" in the kernel module Makefile so stdarg.h can be picked up. It did not work (while building, another reference to stdarg.h in the official kernel header was not being resolved).
I finally created a symlink directly under:
/usr/src/linux-headers-4.15.0-42-generic/include
$sudo ln -s /usr/lib/gcc/i686-linux-gnu/5/include/stdarg.h stdarg.h
This was just enough to solve the compilation issue.
I am wondering if the kernel headers should come with an implementation of stdarg.h by default (that is the first time I encounter this issue). I have also read that the compiler provide one implementation and most of the time it is better to use the compiler version.
Updated note: if the above solution still does not solve the problem:
Before running make again, do a make clean. Do a ls -la in the folder and look for a ".cache.mk" file. If this is still there, remove it and run "make" again. It should solve the problem.
I had the same issue with CentOS 9, and the other answers didn't work for me. Apparently the problem is that in more recent kernels, it shouldn't be <stdarg.h> but <linux/stdarg.h>. With virtualbox guest additions 6.1.34, it correctly checks for kernel with a version of 5.15.0 or more. But my kernel is the 5.14.xx, meaning the include for stdarg.h is wrong.
Solving the issue
Dependencies
Install all the dependencies for the guest edition
gcc make perl kernel-devel kernel-headers bzip2 dkms
Installation
Run the Guest Addition installation like you would normally. It will fail by saying it is unable to compile the kernel modules. That's expected. It will copy all the file we need to the VM disk.
Editing
We now need to edit the erroneous files.
/opt/VBoxGuestAdditions-6.1.34/src/vboxguest-6.1.34/vboxguest/include/iprt/stdarg.h
/opt/VBoxGuestAdditions-6.1.34/src/vboxguest-6.1.34/vboxsf/include/iprt/stdarg.h
On line 48 (may change for different versions), it check for a version of Linux and select the correct header depending on the version. We need to replace if RTLNX_VER_MIN(5,15,0) with if RTLNX_VER_MIN(5,14,0) in both files.
Compile the kernel modules
We can now compile the kernel modules, and the error should be gone.
sudo rcvboxadd quicksetup all
I personally got an error the first time, but then I recompiled without changing anything and it worked.
Remember that it's just a workaround, it may not work with different versions.
If you using Arch Linux with zen-kernel:
sudo CPATH=/usr/src/linux-zen/include/linux vmware-modconfig --console --install-all
I had the same problem with VirtualBox 6.1.0 running archlinux with kernel 6.1.9.
I downloaded VirtualBoxGuestAdditions_7.2.0.iso file from https://download.virtualbox.org/virtualbox/7.0.2/ link(you may select more appropriate to your VirtualBox version) and assigned as an optical drive to virtualbox machine. After start of the system running blkid command on terminal showed the name of CD rom device which was /dev/sr0. then I created iso folder on
/mnt folder
mkdir /mnt/iso
and mounted cd drive to that folder
mount -o loop /dev/sr0 /mnt/iso
after I cd'ed to /mnt/iso
cd /mnt/iso
and manually run VirtualBoxGuestAdditions.run script
sh ./VirtualBoxGuestAdditions.run
which successfully compiled and istalled required virtualbox guest modules.
Now everytime I update kernel version I redo the same procedure. And it work fine.
It also remove old 6.1.0 guest additons folder.
I am trying to install xen on Centos 7 following this guide.
When I run the command "xl info" the following error appears:
xc: error: Could not obtain handle on privileged command interface (2 = No such file or directory): Internal error
libxl: error: libxl.c:116:libxl_ctx_alloc: cannot open libxc handle: No such file or directory
cannot init xl context
In the followed guide it says that I should have the following line in module 2 and in mine is not present even thought it clearly says it's a bug on Centos 6.I don't know if this is related or not.
title CentOS (3.4.46-8.el6.centos.alt.x86_64)
root (hd0,0)
kernel /xen.gz dom0_mem=1024M,max:1024M loglvl=all guest_loglvl=all
module /vmlinuz-3.4.46-8.el6.centos.alt.x86_64 ro root=/dev/mapper/vg_xen01-lv_root rd_LVM_LV=vg_xen01/lv_swap rd_NO_LUKS KEYBOARDTYPE=pc KEYTABLE=uk rd_NO_MD LANG=en_GB rd_LVM_LV=vg_xen01/lv_root SYSFONT=latarcyrheb-sun16 crashkernel=auto rd_NO_DM rhgb quiet
module /initramfs-3.4.46-8.el6.centos.alt.x86_64.img
Thank you for your help.
Is the server booted into the Xen kernel? If you run uname -a you should see something like 3.4.46-8.el6.centos.alt.x86_64. (The 'alt' indicates the Xen kernel.)
Apparently it requires mutiboot2 which RH aren't including because of security issues.
Google your message. You'll find it.
I'm trying to move away from running an application using OpenCL (on an Intel GPU, using beignet) as root all the time. I seem to have run into some permission issue though. clinfo seems to show the same permission issue. Is there some easy way of finding out what permissions/capabilities are needed?
When I run clinfo from the Linux console as an ordinary user I get the following:
drm_intel_gem_bo_context_exec() failed: Invalid argument
/dev/dri/card0 not authenticated
Device open failed, aborting...
error in /home/magnus/lcam-deb/libbeignet-lcam/src/cl_api.c line 298
Invalid device
As root it works fine.
If I start X as the same user and then run clinfo in an xterminal it works just fine too.
For me the solution was passing drm.rnodes=1 to the kernel at boot. I found that information hidden in the How to run section on the beignet wiki.
I want to make a virtual machine for web development on archlinux guest that acts like vagrant box. I don't want to use vagrant box because I want to learn how to do things on my own first and I want to keep the disk space used by the machine at minimum as possible. For this I have installed and configured apache2, php, mariadb with a total of 640M used on disk. I have forwarded guest 80 port to host 127.0.0.1:8080.
I encounter an error with the vboxfs module, I have installed virtualbox-guest-module as described here and after a machine reboot tried:
mount -t vboxfs share_name mount_location and I get this error unknown filesystem type 'vbox'.
I have searched google and all the results make reference to the virtualbox-guest-utils from archlinux but the problem is I don't need all the dependencies that package has (alsa, xorg, video driver etc.) and I don't know witch deps I need or I don't need from that package... so I wander if it is possible and it is enough to use just the vboxfs module to be able to use the share functionality from Virtualbox.
You made a typo. It should be vboxsf instead of vboxfs. I did the same and was wondering why it doesn't work. So the full command is:
sudo mount -t vboxsf share_name mount_location
To remember the correct type you can think of it as the abbreviation of VirtualBox Shared Folder.