Database Develop

What is Kernel ?

I am new here, and I am very confuse about kernel.
I know what ROM is, and the benefit of custom ROM. But I am not sure about kernel. What is it exactly? Please give me a simple explanation.
Is the kernel included in rom when I install a custom rom?
Beside THat i don't have the ability to unlock bootloader coz manuf above 29 w11a32 so what is the issue.
and i think kernel is the reason that coz my phone soft brick more than a time coz this what is called kernel any help ???

1st: Hi, and welcome to the forum hope you enjoy your stay
2nd. Ok, a kernel is what the phone manages its power from. it controls the power and battery on your phone.
press the thanks button if i helped

hello..
you should have searched and read before asking.. i mean i am also new but i have successfully learnt what a 'noob' can maximally know like about roms, kernels. etc..
refer to this very guide... it will give all answers required by you related to kernel roms bootloader etc..... hopefully..
http://forum.xda-developers.com/showthread.php?t=1590266
and about the bootloader thing... its just that its not recommended to unlock it after 11w29 series..
These phones ship with a revamped chipset configuration having the security hole the boot loader unlock uses effectively closed. This means that upon unlocking the boot loader your phone will end up as a hard brick - and you will have NO means to revive the phone yourselves. You either have to send it off to Sony Ericsson for repair (recommended solution) or find a phone repair shop being able to resurrect shot devices!
refer to the foll thread:
http://forum.xda-developers.com/showthread.php?t=1481630

kernel is something like bridge between HW and the SW. SW (ROM, apps,...) communicates with HW (camera, display, digitizer,...) through kernel
if you want some more info, look here

Hi, welcome to XDA!
The X8 phone runs Android.
Android is a Google led variation of Linux kernel.
Linux is an Open Source (a share and share a like philosophy) kernel that can run on pretty much anything. It is like the engine of a car (though I wouldn't take the analogy too far).
On top of the Kernel, various layers of software are placed to either form a desktop environment, a server environment, the X8 stock software or any other Android phone. (Like the differing body shapes of cars, though again I would not take the analogy past this loose interpretation! )
This software consists of things like drivers (enabling inputs such as the touchscreen to interact with the Kernel) through to your homescreen, through to Apps you download.
So to recap, the Kernel is the core of the phone's software and any collection of software on top of the kernel is known as a ROM! They are not entirely separate though and very much linked together, joined at the hip, so to speak.
The phone when you buy it comes with a Kernel and ROM, both created by Sony Ericsson from the software (code) that Google provides, they customise it the way they feel is best for the look they want from their phones.
If you want a different look or feel, a custom ROM (a ROM not created by SE but another team of people who create software, known as developers!) is a good option.
A custom Kernel goes that one step further and allows for greater tweaking on the part of the developers. Some ROMS require a custom kernel for parts of the ROM software to work properly.
Hope that helps

Hi nlao,
Welcome to the community.
Please take some time to Introduce Yourself and read FORUM RULES.
Hope you enjoy your stay here, and help others in the future.
Have you already learned what kernel is and its benefits?

For me : Kernel = BIOS and ROM is windows
Sent from my X8 running nAa and D_d piece of art called MiniCM9

CosminAdriaan said:
For me : Kernel = BIOS and ROM is windows
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Click to collapse
Whilst I like the analogy its not so accurate as Windows has a Kernel too! When using either windows or Linux on a PC you have this basic model:
BIOS --> Kernel --> Software Collection
A somewhat detailed but better written explanation than I could achieve can be found at History of GNU, Linux and Gnome, the relevant section has been pasted below:
"A fundamental misunderstanding is the relationship between Linux and operating systems. Linux is the low level code that interacts with and controls the hardware of the computer (whether it is an Intel 486, Pentium, Sun Sparc, or a Merced). This is the kernel of the operating system, providing routines to help applications talk to each other, allowing many applications to share the CPU at the same time, and managing the use of memory, allowing many different applications to run at the same time without interfering with other applications. Linus Torvalds wrote the first Linux kernel in 1991 and it continues to be actively developed today by Linus and a core team of international developers.
While the kernel is crucial, it is the larger suite of software that sits on top of the kernel that provides the functional operating system."
---------- Post added at 10:36 AM ---------- Previous post was at 10:32 AM ----------
deedii said:
Hi nlao,
Welcome to the community.
Please take some time to Introduce Yourself and read FORUM RULES.
Hope you enjoy your stay here, and help others in the future.
Have you already learned what kernel is and its benefits?
Click to expand...
Click to collapse
Hi deedii, thanks for the Hi! I have posted a little hi message! I have been using Linux for years and have played about with custom kernels for my PC but am new to Android hacking as it has its own nuances and is different to something like Debian!

I got now What is the kernel mean. thanks to all of u for ur replies.
there's so many ROM that i can't flsh it on my phone due to kernel and i think to flash kernel u have to unlock bootloader. and manufacture of my phone doesn't support unlock coz will make a hard brick . for instance i want to flash prime hd8 i tried but it coz a soft brick>>>>>???? what to do

nlao said:
Hi deedii, thanks for the Hi! I have posted a little hi message! I have been using Linux for years and have played about with custom kernels for my PC but am new to Android hacking as it has its own nuances and is different to something like Debian!
Click to expand...
Click to collapse
what flavor do you use dude?

[Q] Building / porting for a "unusual" device

Good Afternoon, people.
I am brazilian and I have a smartphone that did not get into US and European market. It's name is "Motorola D3" and the number associate to it is "XT920".
Motorola Brazil were suposed to provide de newest rom for this device (marketing promissess). It took they almost 1 year to launch the Android Kitkat version 4.4.2.
The problem is: We want the Cyanogenmod in our device and all the newest ROM's.
That been said, I start to study to try yo port or Build a AOSP ROM to XT920 and, therefore, a CM11.
No threads on "how to port / build" a rom for a New device went trhough this problem. This device runs as a Mediatek MTK6577. I've seen that the kernel for this processor was released, but I don't know how to handle the kernel with the device and ROM properly.
Another doubt is: what is the difference between port and build a ROM? I've seen videos of porting and building and it is not clear to me.
I have reached the point where I have to download the drivers, but, in the tutorial the person was dealing with a NEXUS, wich is much easier to build, since it have a native android support.
Anyway, I want to keep this project going, and I really need some help with this questions.
Thankyou

digo_santista said:
This device runs as a Mediatek MTK6577.
Click to expand...
Click to collapse
You're screwed. MTK devices are extremely nightmarish to work with. Their kernel source is a mess and the platform source is an even bigger mess.
Even people who have had access to a complete OEM source code tree for an MT6589 device didn't succeed in getting the hacks to play nice with an AOSP source tree.
Android One has helped somewhat with devices that are released as part of the One program, but non-One MTK devices are still a nightmare.
The process of doing an AOSP bringup for a new device isn't particularly well defined because it is different for every device in existence. The only way to learn is by doing.
It helps a lot if a device with a similar chipset to yours is supported by whatever project you're trying to work with - for example most mid-to-high-end Qualcomm chipsets are not very difficult to work with. But MTK devices were nearly impossible to support with AOSP-derivative projects prior to One, and even after One, it seems like only Android One devices are "clean" enough to leverage Google's improvements to MTK support.

:/ should I waste more time or just drop it?
Entropy512 said:
You're screwed.
Click to expand...
Click to collapse
What should I do? I just quit without trying? I understand that this is a huge problem. But, if I decide to take the chalenge, is there a chance to succeed?
I am trying to figure this out and I didn't found an answer to this question: can I use the kernel that is packed with my stock ROM (provided by motorola) to build or port a CM11 ROM?
Sorry to bother, but I is really keeping me up at night
Regards,
Cassio Rodrigo

Xiaomi Scandal

Hey guys, I suppose some of you have had a xiaomi in the past and I have two questions for you and maybe someone that has some knowledge about xiaomi.
1) Currently how's Xiomi dealing with privacy? I remember 1 or 2 years ago Xiaomi has hit with strong reports of leaking information to their government (chinese) and everything we did on the phone would be seeded to their servers, even SMS's and other stuff..
2) How's the ROM support usually for Xiaomi? Do they usually get a stock based ROM, which has no bloatware and some nice tweaks?
Thanks everyone!

Afaik, being a mi3 user, they had a "data sharing" option on by default in miui which is now changed to be off. Personally i never considered it much as there were already devs who had made custom rom for the device, i think over the last two years i might only have used miui for about 4 to 8 months.
No bloatware, but if u r not a previous user, u might find some apps useless (it has its own clean master replacement app). So yeah, there are a lot of options for tweaks n stuff by default too. Hopefully this answers your questions. (and add a question mark to the title, it looks like u r going to rant about Xiaomi by reading the title, lol)

arnabbiswasalsodeep said:
Afaik, being a mi3 user, they had a "data sharing" option on by default in miui which is now changed to be off. Personally i never considered it much as there were already devs who had made custom rom for the device, i think over the last two years i might only have used miui for about 4 to 8 months.
No bloatware, but if u r not a previous user, u might find some apps useless (it has its own clean master replacement app). So yeah, there are a lot of options for tweaks n stuff by default too. Hopefully this answers your questions. (and add a question mark to the title, it looks like u r going to rant about Xiaomi by reading the title, lol)
Click to expand...
Click to collapse
Do you think there will be much custom rom/kernel support for the Mi 5 (or does this depend on Xiaomi allowing for an unlocked bootloader together with release of kernel sources) ?

SlyUK said:
Do you think there will be much custom rom/kernel support for the Mi 5 (or does this depend on Xiaomi allowing for an unlocked bootloader together with release of kernel sources) ?
Click to expand...
Click to collapse
There will sure be support for custom roms even when the kernel source isn't there, my device had custom roms even before kernel source was released, although there were a bit bugs due to it and only a few (like 5 to 10) custom roms were there, bit with the release of sources, it jumped to 50+. And my device had the bootloader unlocked by default, which even i didn't knew until i rebooted to it. Although the fastboot wasn't able to get the info about the bootloader (like version, etc). IDK if any new devices require to unlock it but i don't think it should be hard as they support it, so that won't be a barrier for development.
TL;DR- less n buggy roms w/o kernel source, floods of roms and custom kernels after source, nothing to concern about bootloader.

There maybe some rom development from a few people that get the device and maybe from cm. But that's about it. Non of the big name team roms will have official versions, just maybe ports.
As for the security and privacy. That is up in the air as it seems even on custom roms they some how have managed to still keep track of the devices. One person on the MI note found that even while not on miui for months that they still had a current backup of all his apps and info.
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zelendel said:
There maybe some rom development from a few people that get the device and maybe from cm. But that's about it. Non of the big name team roms will have official versions, just maybe ports.
As for the security and privacy. That is up in the air as it seems even on custom roms they some how have managed to still keep track of the devices. One person on the MI note found that even while not on miui for months that they still had a current backup of all his apps and info.
Website signature
Click to expand...
Click to collapse
With regards to porting an official rom, I suppose these would be regarded as Unofficial versions. If that is the case is there any real disadvantage in having the "Port" as opposed to have the "Official" version ?

Ports normally will have some bugs as this happens due to not having some things for device built into the code.

Data leak & Software development
Yes I also heard that even with a custom ROM on the device they still found a way to make the device connected and synching information with their servers, which I don't find that funny..
I wanted to know if this data leak is still present in the previous flagship, anyone tested it recently?
It's good to know that it has nearly no bloatware from what you are saying me, but if it has something I don't find useful I may just freeze the app.
Also does anyone know if Xiaomi usually takes long times to update the software of their devices (I heard that they were an exception in relation to other Chinese manufacturers) and release the kernel sources for the ROM developing community or are they pretty good on this area?
Thanks!
:good: :good: :good:

No they are terrible about it. Normally when they post the kernel source it is incomplete and broken.
As for updating. Until very recently they based their os on 4.4 and when asked why they said they didn't care about official android versions.
As for bloat that depends on how you look at it. Miui is about as bloated as TW or HTC Sense.

@zelendel In terms of big name team roms having official versions, would kindly give a few examples ?

SlyUK said:
@zelendel In terms of big name team roms having official versions, would kindly give a few examples ?
Click to expand...
Click to collapse
The biggest are the one or two devices (cant remember their names off the top of my head) that were able to get/fix the kernel source and device trees which CM picked up. So some of the teams that use CM source as a base like AICP also picked up Official versions for the devices.
Then you have the Roms that are based on AOSP instead of CM. As they dont use CM as a base ( Maybe some parts) These roms like Slim or Dirty Unicorns seldom see official versions of the rom. Normally you might get a port here and there. It all depends on if the one of the devs gets the device as most teams don't offer official support for devices they do not own.

Help with Root/Recovery/ROM

Hey everyone. I'm just wondering what the latest developments are as far as custom recovery and ROMs go for the Z3+ single sim unit?
I've had the phone almost a year, and with warranty about to expire, and some performance issues (disappearing flashlight toggle, and laggyness in general at times), I think I'm finally ready to dump the stock room and go for something custom.
I don't have much free time to research the topic, hence this post, so I apologise if this has been discussed recently. Last I read, there were a lot of steps to get root and recovery, and at the time, were no good custom ROMs for the Z3+, so really no point to voiding warranty, IMO. From browsing the dev forum, it looks like there are at least a few ROMs now.
So can someone tell me, or direct me to a post, describing the process to unlock the bootloader (mines locked), get root, and install twrp and a rom?
Thanks, I appreciate the help
Sent from my E6553 using XDA-Developers Legacy app

I tried nougat and didn't like it, nothing is better than MM and there are also some worse parts.
My aim to update N was to have a dark theme with apps included. At last, I decided on stock MM rom 32.2.A.5.11 with theme ready apps by Black Out team, OM5Z kernel and twrp 3.0.2.0.

Compiling a kernel with usb-hid support for lenovo k3 note

Hi Everyone !
I am a noob here and in the android kernel space too .
I have seen this USB-HID project here : https://github.com/pelya/android-keyboard-gadget and seen many kernels for the same, however there isn't any for lenovo k3 note and in general for any mediatek devices ( not sure about this one though ).
Coming to the point, I won't be asking this question if I knew exactly what to do here.
Although the github mentions how to compile custom kernel and I did see a few videos on how to create a custom kernel ( which were pretty good to say the least ).
However I don't understand which kernel source to choose and all that cause , in the github repo it gives an example for nexus device and then say that "change them for your device accordingly.".
So, for my lenovo k3 note what all do I have to change "accordingly" ?
Like in the first line it mentions
Code:
git clone https://android.googlesource.com/platform/prebuilts/gcc/linux-x86/arm/arm-eabi-4.8
and then
Code:
git clone https://android.googlesource.com/kernel/tegra.git
So , how does it change for my device ?
I know that my device has octacore ARM processor, so arm thing should remain the same , right ?
What about the tegra thing, googling it finds me that its the nvidia processor but mine is mediatek, so that should change "accordingly" , but then again change to what ?
Sorry, for asking such noobish questions, I know there are great people out here with way better expertise than a noob like me and so am here.
I don't fear experimenting on my phone.
I did somewhat got stuck in a boot loop a few days back and got to use SP flasher to get it runninng again, I installed AOSP extended on my k3 device alongwith twrp.
I was trying to install nethunter and although it got installed but it's hid device wasn't showing up ( perhaps that needed the correct kernel to get it working ).
Thanks guys/gals.
Aniket
P.S. I am not someone who wants to get the work done from you guys, I am ready to get my hands dirty. Just guide me, how to proceed with that and I will comply :angel:

I'm in the same boat but with aLenovo P2