If you use OMNIROM on your i9100 and you used to update your phone daily, you might be stuck at samsung boot logo since the February 12th nightly update.
Symptoms are a samsung logo bootloop and impossibility to access the recovery. Good point is that the download mode is functional.
To get back your i9100 to life, without flashing a complete Samsung Stock ROM, a solution is to flash a custom kitkat kernel compatible with Odin.
I converted the Gustavo_s kernel ([KERNEL][09/02]Kernel for CM10.2/CM11/Omni 4.4/Slimkat with stweaks support to a .tar file Odin flashable. I hope Gustavo_s will let me share this, I clearly don't want to assign me the merits of his kernel.
This worked for 2 Galaxy S II using OMNIROM and stucked since the update.
You can find the file down bellow. I hope this can be helpfull for people.
1) download the kk-kernel-09-02-TWRP.tar file
2) open Odin
3) click on PDA and select the kk-kernel-09-02-TWRP.tar file
4) put your i9100 in Download Mode (Vol_down + HOME + POWER when it is shut down)
5) connect your phone, and flash it in Odin