5,603,981 Members 43,704 Now Online
XDA Developers Android and Mobile Development Forum

Kexec, and a Proof-of-Concept Source-Built Kernel (Bootloader Workaround)

Tip us?
 
CMTeamEpic
Old
#1  
Recognized Developer - OP
Thanks Meter 1008
Posts: 32
Join Date: Jun 2012
Default Kexec, and a Proof-of-Concept Source-Built Kernel (Bootloader Workaround)

Team Epic announces a proof-of-concept source-built kernel for the Verizon SGS3, complete with kexec hardboot support. This kernel serves two purposes:

1. To be included in custom recovery images, as it proves the capability of booting-via-kexec custom kernels from recovery.

2. To serve as a proof-of-concept boot kernel, to demonstrate that custom kernels are capable of running on the Verizon SGS3 in its present form.

Please see our blog post, Kexec, and a Proof-of-Concept Source-Built Kernel for the Verizon SGS3, for full details and source links.

CyanogenMod's Team Epic specializes in Sprint's flagship Android phones on Sprint.
If you appreciate our work, please consider supporting us with a tiny contribution. Thanks!
The Following 72 Users Say Thank You to CMTeamEpic For This Useful Post: [ Click to Expand ]
 
ruvort
Old
#2  
ruvort's Avatar
Senior Member
Thanks Meter 405
Posts: 1,492
Join Date: Aug 2010
Awesome! Thank you so much for your guys efforts

Sent from my HTC Rezound via Tapatalk

MyColorScreen
The Following User Says Thank You to ruvort For This Useful Post: [ Click to Expand ]
 
ceo.mtcl
Old
#3  
ceo.mtcl's Avatar
Senior Member
Thanks Meter 393
Posts: 2,093
Join Date: Aug 2008
Location: St. Paul, MN
Good luck guys.

☞ sent from my GS3
Current Phones:
๑۩۞۩๑ LG G2 AT&T ๑۩۞۩๑

Benefits of International Samsung Galaxy S3 for US (AT&T) users
 
mkasick
Old
(Last edited by mkasick; 9th July 2012 at 07:53 AM.)
#4  
Recognized Developer
Thanks Meter 823
Posts: 470
Join Date: Aug 2009
Just to confirm, the kexec hardboot approach used here is a bit different from the typical kexec. The main difference is that we actually perform a hardware reboot, reinvoking the bootloader just prior to booting the kexec'd kernel.

The advantage to this approach is that it maintains a high-degree of compatibility and minimizes buggy behavior. The disadvantage is that it requires that the bootloader is capable of booting custom recoveries, which the present Verizon SGS3 bootloader is capable of doing.

Thus, it's very important that folks do not apply any over-the-air (OTA) update, until it is confirmed that custom recovery booting remains intact.

If it eventually arises that booting from a stock kernel/recovery is necessary, then it's likely a bunch of kernel bugs will have to be fixed, and it might still have compatibility issues observed in previous kexec attempts. It's linked in the blog post, but there's a bit more of a technical description of the hardboot approach in this old thread.

Thanks to invisiblek and captjtkirk for testing.
The Following 16 Users Say Thank You to mkasick For This Useful Post: [ Click to Expand ]
 
droidfta
Old
#5  
Member
Thanks Meter 3
Posts: 41
Join Date: Apr 2010
you guys are awesome xda has the best devs ever! I worship you guys!
The Following User Says Thank You to droidfta For This Useful Post: [ Click to Expand ]
 
Schaweet
Old
#6  
Senior Member
Thanks Meter 155
Posts: 617
Join Date: Aug 2010
Wow! Thanks for taking the time to do this even though you guys aren't vzw owners. Great example of how great this community is.

Sent from my DROIDX using xda app-developers app
 
deitiphobia
Old
#7  
Senior Member
Thanks Meter 20
Posts: 145
Join Date: Nov 2010
Location: Pasadena, CA
Unbelievable...you guys are awesome.

Jelly Bean here we come!

 
jh120
Old
#8  
Junior Member
Thanks Meter 3
Posts: 17
Join Date: Oct 2010
Quote:
Originally Posted by mkasick View Post
Thus, it's very important that folks do not apply any over-the-air (OTA) update, until it is confirmed that custom recovery booting remains intact.
Forgive my paranoia, but does Verizon have the ability to force an OTA without us pressing an "OK" button?

Thanks to all who worked on this, you're awesome!
The Following 2 Users Say Thank You to jh120 For This Useful Post: [ Click to Expand ]
 
Neverendingxsin
Old
#9  
Neverendingxsin's Avatar
Senior Member
Thanks Meter 1105
Posts: 1,888
Join Date: Dec 2009
Location: Virginia
Quote:
Originally Posted by jh120 View Post
Forgive my paranoia, but does Verizon have the ability to force an OTA without us pressing an "OK" button?

Thanks to all who worked on this, you're awesome!
nope. you have to accept the OTA




The Following 2 Users Say Thank You to Neverendingxsin For This Useful Post: [ Click to Expand ]
 
densetsu86
Old
#10  
Senior Member
Thanks Meter 18
Posts: 163
Join Date: Aug 2011
Just a question does the kexec allow the sgsiii to use both cores. I have heard that kexec on both the droid razr and droid 3 doesn't allow for dual core yet. Any such issues with sgsiii or is it too soon to tell?


Sent from my DROID X2 using xda app-developers app

Tags
notdevelopment!
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes