## How to obtain unique Android information from the android kernel?

I want to obtian some unique informaiton, from example, the IMEI, Android ID, phone number, etc., from the android kernel programtically. So,
What kind of unique information can be obtained from the android kernel?
How to obtain the above information from the kernel prgoramtically?

Thank you very much!

## boot – Ubuntu 20.04 with ZFS, changing kernel version results in “Failed to load ZFS modules”

If I boot with a kernel only a single minor version above (or below) the three shipped with my ubuntu 20.04 I get :

(         0.691104) Initramfs unpacking failed: Decoding failed

Manually load the modules and exit.

Busybox v1.30.1 (Ubuntu 1:1.30.1-4ubuntu6.1) built-in shell
Enter 'help' for a list of built-in commands.

(initramfs)_

If I select my normal kernel version : 5.4.0.40.44 then it boots normally.

I followed the “at install time” choice of this guide : https://askubuntu.com/a/1245550/573671
and I’m still getting this error.

Why did his fix not work for me?

## boot – Main Kernel can no longer be loaded

After a reboot my main Kernel can no longer be loaded. It is stuck at “Loading Linux <kernelversion>-generic”. I can boot with one of my backup kernels. Recently I executed

sudo apt-get purge \$(for tag in "linux-image" "linux-headers"; do dpkg-query -W -f'\${Package}n' "\$tag-(0-9)*.(0-9)*.(0-9)*" | sort -V | awk 'index(\$0,c){exit} //' c=\$(uname -r | cut -d- -f1,2); done)

to free up space in the boot partition. I did that in the past and it caused no problems. I do not know if I rebooted between the last time I executed that command and if it might be related to my kernel problem.

What should I do to solve this? What information or logs do you need?

## testing – Kernel tests: Url toString with language option

In a Kernel test I need to test the result of an url object per language. But the test doesn’t consider the language settings.

Example:

public function register(ContainerBuilder \$container) {
parent::register(\$container);

\$language = Language::\$defaultValues;
\$language('id') = 'de';
\$language('name') = 'German';
\$container->setParameter('language.default_values', \$language);
}

protected function setUp() {
parent::setUp();

ConfigurableLanguage::createFromLangcode('fr')->save();
ConfigurableLanguage::createFromLangcode('it')->save();
}

public function testUrls() {
\$languageManager = \$this->container->get('language_manager');
print_r(\$languageManager->getLanguages());

\$url = Url::fromRoute('<front>');
\$url->setOption('language', \$languageManager->getLanguage('fr'));
print_r(\$url->toString());
}

Output:

Array
(
(de)
(fr)
(it)
)

# Output of toString()
/

The output of toString should be /fr instead of /

I discovered that the DrupallanguageHttpKernelPathProcessorLanguage outbound processor is missing, when UrlGenerator::processPath() is called from the Kernel test. Therefore, I registered it in the Kernel test’s register method, but that doesn’t solve the problem.

## macos – Recording audio from other applications (or entire system) without kernel extensions

I’m trying to programmatically record audio from other applications (or the entire device) on a mac to allow for the screensharing/mirroring of video+audio. While this is obviously possible, Soundflower and other applications I’ve found all seem to use Kernel Extensions, which would be unreasonable to include in what is a purely userland application.

Changing audio output devices, and clicking through permissions panes is fine. But is there any way to record system audio without kernel extensions? It would seem like recording audio output is far less dangerous than screen recording, and should be allowed, but doesn’t appear to be.

## Linux kernel and CPU AMD A10-5757M

hi guys please help me choose the right kernel parameters to get maximum performance on the AMD A10-5757M processor
which config arch/x86/Kconfig.cpu to choose?

## kernel – Linux Deploy Ubuntu share folder

I wasn’t sure if I had to ask this question on a Linux Exchange or on the Android one, but since folder sharing is working fine on the Linux that are running on my computer, I thought that it is an Android side issue.
I am trying to share a folder between two Linux Deploy environments. I have tried to install nfs-kernel-server however I am having an error showing that the kernel does not support nfs. When I am using uname -a the kernel that Ubuntu prints is the Android’s one so I guess that the Android kernel does not support the nfs module.
I have, also, tried using Samba. The server side was set up successfully. When I am trying to mount the shared folder using mount -t cifs //192.168.1.5/mirror /mirror, I am facing a mount error cifs filesystem not supported by the system. After some googling I found out that using modprobe cifs could resolve the issue however the module cifs does not exist on the Android kernel. It seems that the issue in both cases the issue seems to be the Android kernel, is there any way to add nfs or cifs support to the Android kernel? If that’s not possible how could I share a folder between two Linux Deploy environments?

## samsung – Can we build aarch64 android kernel with 32bit os?

i have a android device with aarch64 (64bit) kernel. Im looking for Kali NetHunter kernel for my device. But no developer build that for my device. Then, im trying to build my own kernel. I successfully build a kernel for 32bit device. My question is Can I build aarch64 kernel with 32bit linux os? if not, why?

My device : Samsung Galaxy J4 (SM-J400F) (kernel source is available in Samsung opensource site) Linux OS I use : Ubuntu 16.04 32bit

## graph theory – Positive vector in the kernel of an antisymmetric “adjacency” matrix

For $$ninmathbb{N}^*$$, let $$G=(V,A)$$ be an oriented graph, stronlgy connected with $$n$$ vertices. Let $$Minmathcal{M}_n(mathbb{R})=(m_{i,j})$$ be an skew-symmetric matrix of size $$n$$ and rank $$r$$, such that for all $$i,jin V$$: $$ilongrightarrow jLongleftrightarrow m_{i,j}>0$$ (hence $$M$$ is a kind of adjacency matrix for $$G$$). Is there any necessary and sufficient condition on $$G$$ and $$r$$ ensuring that there exists a positive vector in $$text{Ker}(M)$$?

I’ve tried several matrices for $$nin{3,4,5}$$ and it seems that, given $$G$$ and $$r$$, the fact that there exists a positive vector in $$text{Ker}(M)$$ does not depend on the values of the exact values coefficients $$m_{i,j}$$, but I do not know how to predict that such a vector exists. I have just noticed that given $$G$$, the answer of the question can vary with $$r$$.

## machine learning – How to understand mapping function of kernel?

For a kernel function, we have two conditions one is that it should be symmetric which is easy to understand intuitively because dot products are symmetric as well and our kernel should also follow this. The other condition is given below

There exists a map $$φ:R^d→H$$ called kernel feature map into some high dimensional feature space H such that $$∀x,x′$$ in $$R^d:k(x,x′)=<φ(x),φ(x′)>$$

I understand that this means that there should exist a feature map that will project the data from low dimension to any high dimension D and kernel function will take the dot product in that space.

For example, the Euclidean distance is given as

$$d(x,y)=∑_i(x_i−y_i)^2=+−2$$

If I look this in terms of the second condition how do we know that doesn’t exist any feature map for euclidean distance? What exactly are we looking in feature maps mathematically?