My G935F shows “Could not do normal boot invalid kernel length” when attempting to boot into TWRP or turn on the device normally. The only thing I can access is ODIN. This happened after attempting to update TWRP and LineageOS. From looking online, I believe I can get a kernel and select the AP option in ODIN and flash a kernel as long as it is in .tar format. I was previously using PRIME kernel https://forum.xda-developers.com/s7-...1-4-0-t3678159 so I looked in the latest download from there but there are no .tar files, only a bootimg.tar.xz and a ramdisks.tar.xz. I tried extracting bootimg.tar.xz to a bootimg.tar and flashing that, but ODIN says it failed:

<ID:0/003> Added!!
<ID:0/003> Odin engine v(ID:3.1210)..
<ID:0/003> File analysis..
<ID:0/003> SetupConnection..
<ID:0/003> Initialzation..
<ID:0/003> Get PIT for mapping..
<ID:0/003> Firmware update start..
<ID:0/003> NAND Write Start!!
<ID:0/003> SingleDownload.
<ID:0/003> g930eur-aosp-Image-r12p0
<ID:0/003> Unassigned file
<ID:0/003> Complete(Write) operation failed.
<OSM> All threads completed. (succeed 0 / failed 1)

I also tried flashing the zip from https://autoroot.chainfire.eu/#odin but ODIN gave me:

<ID:0/003> Added!!
<OSM> Enter CS for MD5..
<OSM> Check MD5.. Do not unplug the cable..
<OSM> Please wait..
<OSM> CF-Auto-Root-hero2lte-hero2ltexx-smg935f.tar.md5 is valid.
<OSM> Checking MD5 finished Sucessfully..
<OSM> Leave CS..
<ID:0/003> Odin engine v(ID:3.1005)..
<ID:0/003> File analysis.. <ID:0/003> SetupConnection..
<ID:0/003> Complete(Write) operation failed.
<OSM> All threads completed. (succeed 0 / failed 1)

I don't know what I'm doing and I'm afraid to mess up my phone beyond repair with ODIN. Can someone please help me? XDA forums has no answer and I don't know who else to ask.

1 Answer 1


I ran ODIN as administrator and was able to flash Chainfire. I was then able to boot in normally, and after that flash TWRP again. Still not sure which step caused that issue but it is resoled now.

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