Android Studio: /dev/kvm device permission denied - 64-bit

Question

When I try to run my Android app on an emulator I get this error:
/dev/kvm permission denied.
I checked the permissions and added the user I am currently logged in with to the kvm group. What is wrong?

Answer 1

As mentioned in the comments, starting with Ubuntu 18.04 and Linux Mint Tara you need to first sudo apt install qemu-kvm.
To check the ownership of /dev/kvm use
ls -al /dev/kvm
The user was root, the group kvm. To check which users are in the kvm group, use
grep kvm /etc/group
This returned
kvm:x:some_number:
on my system: as there is nothing rightwards of the final :, there are no users in the kvm group.
To add your user to the kvm group, you could use
sudo adduser $USER kvm
which adds the user to the group, and check once again with grep kvm /etc/group.
As mentioned by #marcolz, the command newgrp kvm should change the group membership live for you. If that did not work, #Knossos mentioned that you might want to log out and back in (or restart), for the permissions to take effect. Or do as #nmirceac mentioned and re-login in the same shell via su - $USER.

Answer 2

This is how I got it to work in Ubuntu 18.04
sudo apt install qemu-kvm
Add your user to kvm group using:
sudo adduser <Replace with username> kvm
If still showing permission denied:
sudo chown <Replace with username> /dev/kvm
Try it.

Answer 3

Try this, it worked for me:
sudo apt install qemu-kvm
sudo chown -R <username>:<username> /dev/kvm

Answer 4

This is because /dev/kvm is not accessible. To make is accessible from android studio run the below command
sudo chmod 777 -R /dev/kvm
It will ask for your password. After that restart Android Studio.
KVM is required to rum emulator. If you have not install it yet then install it
sudo apt install qemu-kvm

Answer 5

Have you also tried following, it should work:
sudo chown <username> /dev/kvm
sudo chmod o+x /dev/kvm

Answer 6

sudo chown $USER /dev/kvm
Simply running that one command worked for me here in September 2019 running:
Description: Ubuntu 18.04.3
LTS Release: 18.04
Codename: bionic

Answer 7

Step 1: (Install qemu-kvm)
sudo apt install qemu-kvm
Step 2: (Add your user to kvm group using)
sudo adduser username kvm
Step 3: (If still showing permission denied)
sudo chown username /dev/kvm
Final step:
ls -al /dev/kvm

Answer 8

I am using ubuntu 18.04. I was facing the same problem. I run this piece of command in terminal and problem is resolved.
sudo chown $USER /dev/kvm
the above command is for all the user present in your system.
If you want to give access to only a specific user then run this command
sudo chown UserNameHere /dev/kvm

Answer 9

Under Ubuntu, the permissions of /dev/kvm usually look like this:
$ ls -l /dev/kvm
crw-rw---- 1 root kvm 10, 232 May 24 09:54 /dev/kvm
The user that runs the Android emulator (i.e. your user) needs to get access to this device.
Thus, there are basically 2 ways how to get access:
Make sure that your user is part of the kvm group (requires a re-login of your user after the change)
Widen the permissions of that device such that your user has access (requires a change to the udev daemon configuration)
Add User to KVM Group
Check if your user is already part of the kvm group, e.g.:
$ id
uid=1000(juser) gid=1000(juser) groups=1000(juser),10(wheel)
If it isn't then add it with e.g.:
$ sudo usermod --append --groups kvm juser
After that change you have to logout and login again to make the group change effective (check again with id).
Widen Permissions
Alternatively, you can just can widen the permissions of the /dev/kvm device.
Example:
echo 'KERNEL=="kvm", GROUP="kvm", MODE="0666", OPTIONS+="static_node=kvm"' \
| sudo tee /etc/udev/rules.d/99-kvm4all.rules
sudo udevadm control --reload-rules
sudo udevadm trigger --name-match=kvm
FWIW, this is the default on other distributions such as Fedora and CentOS.
Check the effectiveness of the above commands with another ls. You should see output similar to:
$ ls -l /dev/kvm
crw-rw-rw-. 1 root kvm 10, 232 2020-05-16 09:19 /dev/kvm
Big advantage: You don't need to logout and login again for this change to be effective.
Non-Solutions
calling chmod and chown directly on /dev/kvm - 1) these changes aren't persistent over reboots and 2) since /dev/kvm permissions are controlled by the udev daemon, it can 'fix' its permissions at any time, e.g. after each emulator run
adding executable permissions to /dev/kvm - your emulator just requires read and write permissions
changing permissions recursively on /dev/kvm - I don't know what's up with that - looks like cargo cult
installing extra packages like qemu - you already have your emulator installed - you just need to get access to the /dev/kvm device

Answer 10

Here is a simple solution
open the terminal and run the following commands
sudo groupadd -r kvm
sudo gedit /lib/udev/rules.d/60-qemu-system-common.rules
Add the following line to the opened file and save it
KERNEL=="kvm", GROUP="kvm", MODE="0660"
Finally run:
sudo usermod -a -G kvm <your_username>
Reboot your PC and Done!

Answer 11

There's absolutely no need to install qemu-kvm (and all its dependencies) if you only want to run the Android Studio Emulator.
The only thing you have to do is to give your user (i.e. the one you are logged in with) the right to access the /dev/kvm-device.
This is done in three simple steps.
First:
Create the kvm-group
groupadd -r kvm
The option -r creates a system group, i.e. with a GID <= 999 (see /etc/login.defs => SYS_GID_MAX)
Second:
Change permissions on /dev/kvm. This could be done as part of the qemu-kvm-installation, because one of the dependencies is installing qemu-system-common (on current Ubuntu systems, package name may vary), which in turn installs the file /lib/udev/rules.d/60-qemu-system-common.rules containing the following:
KERNEL=="kvm", GROUP="kvm", MODE="0660"
So if you are just create a file /etc/udev/rules.d/60-qemu-permissions.rules containing the above line, you are done with the first step.
Third:
Add your username to the group by executing
usermod -a -G kvm <your_username> - the -a is important for adding your user to the kvm-group. Without that you will overwrite the group-settings for your user to only belonging to "kvm"...
That's it.
For the new udev rule and group setting to take effect it's easiest to reboot and login again.
You can also execute
udevadm control --reload-rules && udevadm trigger
for reloading the rules but you still have to logout and login again with regard to the new group.

Answer 12

I countered the same problem and to solve this issue just type the following commands in terminal for Linux clients
sudo apt-get install qemu-kvm
// type your password
sudo chmod 777 -R /dev/kvm
and after that try running simulator it'll work

Answer 13

sudo setfacl -m u:$USER:rwx /dev/kvm
Worked for me.

Answer 14

I am using linux debian, and i am facing the same way. In my AVD showing me a message "/dev/kvm permission denied" and i tried to find the solution, then what i do to solve it is, in terminal type this :
sudo chmod -R 777 /dev/kvm
it will grant an access for folder /dev/kvm,then check again on your AVD , the error message will disappear, hope it will help.

Answer 15

This Worked For Me on Linux (x18) ☑ Hope It Will Work For You Aswell
sudo chown hp /dev/kvm

Answer 16

Just one slight improvement on Jerrin's answer on fixing this error with Ubuntu 18.04 by utilizing $USER variable available in the bash terminal. So you could use the following commands two commands:
sudo apt install qemu-kvm
Add the current user to the kvm group
sudo adduser $USER kvm
Also if you are still having issues, one other problem for me was the way in which I installed Ubuntu. I made the mistake of checking the box during installation for installing 3rd party software which did not play nice with my nvidia graphics card for development. So I reinstalled Ubuntu with this third party software unchecked.
Then after installation, open up Software & Updates and go to the Additional Drivers tab. Select the most up to date proprietary drivers that have also been tested and apply changes. Should restart the machine for the changes to take affect.

Answer 17

What finally fixed it for me on Ubuntu 18.04 was:
sudo apt install qemu-kvm
sudo adduser $USER kvm
sudo chown $USER /dev/kvm

Answer 18

I tried sudo setfacl -m u:UserName:rwx /dev/kvm . and it works .
In the android studio you need to change : tools> avd manager >(chose the pen to edit your device and change 'graphics' from automatic to software ) to avoid emulator drawable error

Answer 19

Here is what I did:
user#user:~$ whoami
antonio
sudo apt install qemu-kvm
sudo adduser antonio kvm
sudo chown antonio /dev/kvm
last but not least
On Android studio
select File -> Restart IDE
to apply the changes
Then create the emulator

Answer 20

I was in a similar situation with the same error of permissions on /dev/kvm
I had done the necessary installations but not added the user to the kvm group
All I had to do was
sudo adduser <Replace with username> kvm
and ofcourse DON'T forget to restart your Ubuntu instance.

Answer 21

/dev/kvm permission denied android studio
[Motherboard]Set VT(Virtualization Technology) in BIOS and install Virtual Machine

Answer 22

I got this error after updating my ubuntu to 18.04.1. I just download new system image for emulator or you can say that download new emulator and it is worked for me.

Answer 23

Open Terminal and log as admin
sudo su
Go to the dev folder
cd /dev/
Change the kvm mode
chmod 777 -R kvm

Answer 24

Type in terminal:
sudo apt install qemu-kvm -y
sudo chown $USER /dev/kvm

Answer 25

Although KVM is a module built into the Linux kernel itself, it doesn't mean that all the necessary packages are included in your Ubuntu/Linux install by default. You'll need a few to get started, and they can be installed with this command in the terminal:
& sudo apt install qemu-kvm libvirt-clients libvirt-daemon-system bridge-utils virt-manager
Configure the network bridge
In order for your virtual machines to access your network interface and be assigned their own IP addresses, we need to configure bridged networking on our system.
First, run the following Linux command in order to find out what name your network interface has been assigned. Knowing this will allow us to do additional configuration later.
$ ip a
In my case, the network interface is called enp2s0. Yours will likely be very similarly named.
In order to tell Ubuntu that we want our connection to be bridged, we'll need to edit the network interfaces configuration file. Doing this won't negatively impact your connection at all. It'll just allow that connection to be shared with the VMs.
Use code (Visual Studio Code) or your favorite text editor to open the following file:
$ code /etc/network/interfaces
When you first open this file, it may be empty or contain just a couple of lines. Your bridge interface is called br0, so add the following line for the interface to come up by default:
auto br0
Below this line, add the following line for your current network interface (the one who's named you determined earlier).
iface enp2s0 inet manual
Next, you can add the bridge information. These lines tell Ubuntu that your bridge will use DHCP for automatic IP address assignment, and your bridge will manage your current interface.
iface br0 inet dhcp
bridge_ports enp2s0
This is how your file should look once all the changes have been applied (if you also have a couple of lines that were already there, it's fine to have them too):
Save your changes and exit the file.
Add your user to the groups
In order to manage your virtual machine(s) without root privileges, your user will need to belong to two user groups. Run the following commands to add your user to the appropriate groups (replacing user1 with the name of your user):
$ sudo adduser user1 libvirt
$ sudo adduser user1 libvirt-qemu
$ sudo adduser user1 kvm
When you're done, you should restart your system to ensure that all of the changes done to your user and network configuration have a chance to take effect.

Answer 26

In order to make a virtual device in Linux - I have to follow this three command and it helps me to avoid trouble for building avd devices - the process are -
sudo apt install qemu-kvm
sudo adduser $USER kvm
sudo chown $USER /dev/kvm
so, now you are good to go, restart android studio and start building application with emulator.

Answer 27

Provide appropriate permissions with this command
sudo chmod 777 -R /dev/kvm

Answer 28

Running the below command in Ubuntu 18.04 worked for me
sudo chown -R /dev/kvm

Answer 29

If you open your ide with sudo. You are not going to have this problem.