yashsingh1/xdaforums huggingface dataset:
[LG V20 Guides, News, & Discussion] Electrolite_XYZ:
I used TWRP's official app do update my TWRP but something went wrong, TWRP got replaced with fastboot. Is there any way to flash TWRP again without doing the entire process again? Everything I tried failed.
[LG V20 Guides, News, & Discussion] dextructor:
I'm trying to justify why use that app if you can just download and flash withing the TWRP itself, but I'll assume that to use TWRP you need root permissions.

So you need to follow my report on how to flash any recovery with an app. Presuming that you'll download the correct version of TWRP and using the app that I suggested correctly.

And also verify that your fastboot works correctly because that's also important in case of trouble.
[LG V20 Guides, News, & Discussion] Electrolite_XYZ:
I wanted to try it. Being able to update TWRP without rebooting into recovery looked like a neat concept.

There were some TWRP images around this forum but I plan to use the latest version here: https://dl.twrp.me/h990/ That should be fine right?

I'll try it, hope it works better than the official app... anyways my phone is still rooted and booting so it should be fine, if I have any issues I'll ask for help ;)

How can I test that? I tried to flash TWRP using fastboot on my PC but the command stalled with the message: "Waiting for device" most likely a driver issue I guess.

EDIT: Managed to fix the issue, I still used the official TWRP app but I got an unofficial image: https://xdaforums.com/t/recovery-unofficial-twrp-3-3-1-1-2019-10-25.3720239/
[LG V20 Guides, News, & Discussion] dextructor:
It's wise to apply this for everything in life: "It's not because it can be done, that should be done".

There's many potential problems with that approach, for so few benefits, and TWRP releases are so few and sparse that doing it withing the recovery, fastboot (if you setup properly) or the app that I recommended it's more safe.

Yes, if you follow the instructions, download the correct files (from this thread and TWRP) you are on the right track

It's your device, and it's your responsibility. So if you are satisfied using any solution other that was recommended by the members that put those guides, ok, be happy.
[LG V20 Guides, News, & Discussion] Electrolite_XYZ:
The app you sent me only works with .zip. I was having some trouble creating a flashable zip so I tried the official app one last time and it worked.
[LG V20 Guides, News, & Discussion] emdroidle:
The "Your device is corrupted it cannot be trusted and will not work. Phone will restart automatically after a while." message with the red triangle happens with this method. I'm guessing you pulled the battery before it did anything? Simply wait a few extra (around 15-30) seconds and it will boot anyway. There is no way to get rid of that message, so we simply have to live with it on boots.

Making sure, you did upload abootbackup.img to your phone before doing running `dd`? Method 1b is pretty much the same method, just taking advantage of the on-device backup.

No idea. The H990TR wasn't part of the original target so I lack information to target it. My latest experimental kernel should hopefully work on your device, but be aware no one has yet tried it on a H990TR. If you're a very experienced user you can try, but you really need to know how to get out of sticky phone situations since things could readily go wrong.

Okay, that wasn't quite what I expected. Was supposed to be `./fix-h990-cmdline` if you were in the same directory, its a Linux executable, not a shell script. :) Good news is this does give me a potential idea as to what went wrong.

New repackaged version of the kernel, with an updated `fix-h990-cmdline` is attached to this message. Beware this is BETA, it works for me, but may well break for everyone else.

MD5: 97a664259d6e89cb93fc5f9858e4d9f3

SHA1: c50c906c7184381d5c8db37d114356c8699f5572

SHA512: 1cbd0c27b7d858e62f01681e000a2c2d557045fb7fd7d72277d26ed733fba1d851a4a690029d6f9d85c835c7876d5bb4af6681e508ee1e0809f22dfbf2c261c1
[LG V20 Guides, News, & Discussion] kingnose:
This is the new kernel with the fix for the screen freeze, right? I'm guessing it could solve the screen freeze + battery drain issue for me.

Thanks for your hard work, really appreciate it.

EDIT: Is this for the H990DS as well?
[LG V20 Guides, News, & Discussion] Hamodi:
okey i tried it on H990 single sim

this time it do bootup but it take me to secure start-up and ask me to add password , tried to insert my password but didnt work

so i wipped data and flashed kernel again but that didnt work either the kernel crash but this time with green screen .

will try with format data

EDIT:

ok now it do bootup , root seems there (didnt try it yet )

but there is no mobile data network (sim not recognized by the phone)

---------- Post added at 01:55 AM ---------- Previous post was at 01:36 AM ----------

so root is working on H990 single sim ( tried it with titanium backup) works fine

video record seems works too .

the only thing that dont work is the Sim , its not recognized by the phone .

is there any edit i can do with file explorer to make it work ?? [MENTION=6984210]emdroidle[/MENTION]
[LG V20 Guides, News, & Discussion] emdroidle:
I'm not optimistic about fixing that issue via kernel update. The best bet for this issue is to get my firmware update program operational (pretty much a KDZ writer which merely writes portions of the KDZ to the device).

This kernel is supposed to work on H990DS, hopefully the entire range of them.

Bit of news here. There doesn't appear to be any requirement to let TWRP access your userdata, unless you're trying to backup. You can simply flash the SuperSU zip, which takes care of modifying the initial ramdisk and leaves the appropriate breadcrumbs behind for it to finish installation on next reboot (there might be a need to have the SuperSU APK installed beforehand).

That green screen is annoying since I don't know what is causing it. The message is "watchdog timeout", but nothing I'm changing should cause one to occur. Seemed to occur when the kernel's strncmp() function was used, but that is really strange to break.

Okay, this is a highly valuable data point. This means the kernel is operational on a H990, now the difficulty is figuring out where the last problem is... I've got a long list of things to examine to figure out the problem.

What is in /proc/cmdline? (`cat /proc/cmdline`, requires root on the V20; I advise filtering this information, I don't need your phone's serial number and this can qualify as personal information)

Grab a copy of /dev/block/bootdevice/by-name/boot and take a look at it in a binary editor. The boot image command-line is at offsets 0x40 to 0x240, of this 0xDE to 0x158 are important (this is supposed to be modified by `fix-h990-cmdline`). Run `dd if=/dev/block/bootdevice/by-name/boot bs=4096 count=1 | strings` (handy method of getting this information). Of note it should include "model.name=LG-H990", "lge.sim_num=1" and "lge.dsds=none", does it?

Try running the program `tools/fix-h990-cmdline` either at a root shell or while TWRP is running. This program (an executable, not a shell script!) will simply output what it is supposed to be adding to the boot image command-line. Looking at the output should tell us whether it is failing to retrieve the information for modifying the command-line, or failing to modify the boot image.

Can you try rebooting your phone and repeatedly running `adb shell dmesg > dmesg.nnn.txt`? The idea here is to get a look at what is happening as early as possible. My guess is you'll see the modem being repeatedly reset. There is a fair chance you'll be seeing kernel panics about 50% of the time. (the modem reset code apparently isn't well tested since it isn't expected to be run very often)
[LG V20 Guides, News, & Discussion] Hamodi:
okey that been passed by format data and flash again kernel and supersu but what about the mobile data and the sim ?

its cant be recognized by the phone .

the hard thing had been achieved , root is working with no problem

---------- Post added at 02:51 AM ---------- Previous post was at 02:09 AM ----------

where i should run this /proc/cmdline? (`cat /proc/cmdline`, ??

cmd or terminal ??
[LG V20 Guides, News, & Discussion] exadeci:
Oh my bad haha, this kernel doesn't fix it though, the output with the binary from the new kernel gives me exactly:

"LGE model information format version 3.1"

" model.name=LG-H990ds lge.sim_num=2 lge.dsds=dsds androidboot.bl_unlock_complete=false androidboot.authorized_kernel=true"

I couldn't find the strings you mentioned in the boot.img (I've pmed it to you )
[LG V20 Guides, News, & Discussion] kingnose:
[MENTION=6984210]emdroidle[/MENTION]

So that means I should be able to flash the kernel by going to "Install" in TWRP, correct?
[LG V20 Guides, News, & Discussion] Hamodi:
now i cant go back to stock

lgup and uppercut cant recognized my phone !!!
[LG V20 Guides, News, & Discussion] emdroidle:
The mention of a "root shell" should have been a pretty good hint it was meant for a shell on the device, using '/' for separators should similarly have suggested such. Given what I just noticed though, there should no longer be any need for the above steps...

Indeed, missing what was supposed to have been added. :(

Then looking at things and "oh gawd! that was really stupid". I've got a rather strong suspicion I've found the goof. I think I've finally fixed the really stupid goof in the zip file attached to this message.

Yeah, same as most zip files meant for TWRP.

Okay, remember the attached version is BETA, it works great for me, but may very well break for everyone else. This kernel should work on any H990* device, but please have a restore plan ready until large numbers of reports of success come in.

MD5: 3ae0501dbb670b36780fe2dbfee89b62

SHA1: 9a0e6c11c7445f92576cdf3a2743c8fbc6b01319

SHA512: 50492a3db9f81417b011041c6fdbd56e05b0f796f79e46fa926c7201a27a43f6926ce5190be1b02a48056fb1c03b6d65628e67f894aac9f3d285b253c601da0a

This kernel is now on the opener. The H990DS-specific kernel is still present, but this one is now preferred since it should handle all variants, not just one.
[LG V20 Guides, News, & Discussion] exadeci:
[MENTION=6984210]emdroidle[/MENTION] This one is working cheers
[LG V20 Guides, News, & Discussion] kingnose:
[MENTION=6984210]emdroidle[/MENTION]

The new kernel does work, but I got a screen freeze about an hour after flashing the kernel. I pulled the battery and left it powered down (as it was very hot). Will use it for a week (as I have a backup phone) and see if this continues or not.

One thing I've noticed is when the battery is back in (after I've removed it) and I plug the charger to recharge the mostly drained battery, I've noticed that it doesn't quick charge (when I turn the phone back on, I can see it is not quick charging, but when the cable is pulled out and plugged back in, it starts to quick charge from then on)

Thanks for the work!
[LG V20 Guides, News, & Discussion] omnimann:
yes i did upload abootbackup.img to my phone before doing running `dd`

if i keep my phone on while warning is on, it just reboot into same warning screen over and over.

seems i have a locked bootloader, no twrp. and it says in lgup that my phone is US996.

tried lgmobile support tool and it finds my device (H99010F software version) but says LG mobile support tool is unavailble on this phone.
[LG V20 Guides, News, & Discussion] Hamodi:
i have the same **** , i cant find any solution for it !!!
[LG V20 Guides, News, & Discussion] corepda:
It hasnt worked for me. I am through to step 1 and write as per step 8 but then after writing id in android terminal and getting the untrusted app, when I try to enter applypatch /system/bin/atd /storage/emulated/0/dirtysanta, it says not found and runmefirst doesnt do anything. Not sure what i am doing wrong. Thanks
[LG V20 Guides, News, & Discussion] Csetoue:
Any custom ROM available?
[LG V20 Guides, News, & Discussion] UL7RA:
So anyone found a reliable fix for video?
[LG V20 Guides, News, & Discussion] omnimann:
Seeking for solution....

Found this

read user c881jz posts... He had the same problem and managed to fix it..

im still stuck... can`t quite understand what he did..

Let me know if you manage it and how?
[LG V20 Guides, News, & Discussion] kingnose:
It seems like he used a different cable
[LG V20 Guides, News, & Discussion] emdroidle:
Is your phone on a security update after DirtyCOW was fixed? If so then you need to downgrade to a vulnerable firmware, without that there isn't a way to get the DirtySanta bootloader installed and things just don't work.

I suppose using a USB2 port could make a difference. Not what I would have expected.

Problem is these indications strongly conflict. If you successfully reinstalled the locked bootloader, then LGUP would identify your phone as a H990 and not a US996. If weren't successful at reinstalling the locked bootloader; either you would be on full DirtySanta and should have the unlocked bootloader; otherwise with a partial flash you would have a corrupt bootloader and your phone wouldn't get to a point where LGUP would recognized it at all (a corrupt signature would prevent the phone from getting that far).

Has your USB cable gone bad? Is it possible you're actually still on the DirtySanta bootloader and it actually is unlocked? (have you tried getting into fastboot mode, does it work?)

[MENTION=4394458]Leicxan[/MENTION] there are some new technical notes in the opener. I've also done some updates which should have a kernel which works for all H990* variants without needing specific tailoring.
[LG V20 Guides, News, & Discussion] Leicxan:
Thanks for your hard work.

I saw you switch the exfat module to an opensource one from dorimanx, and i also got exfat.ko module from this, but i check your latest kernel file, you use the tuxera's prebuilt one.

I try to add this in defconfig CONFIG_EXFAT_COMPAT_TUXERA=y, but not work..

My H990N got wifi problem so i send it back to the shop, the new one will arrive tomorrow, hope the wifi is working well.
[LG V20 Guides, News, & Discussion] dextructor:
Please pay attention/be aware when using anything for your own sake, because you not can make mistakes, but also lead others with those statements that

are wrong/misleading.

The devs on the app page said clearly:

"Flash a boot/recovery partition '.img' on a supported device."

And I flashed on my devices without problem, so what's the issue here? The devs should put the option to flash recovery on Flash section, but they put on Backup > Flash > Then you select if it's a boot or recovery partition.

I'm glad that you fix your device overall.
[LG V20 Guides, News, & Discussion] Envinite:
I've been using DirtySanta for years on multiple V20 variants and never have the RUNMEFIRST window (on my Windows 11) ask me to "run step2.bat". What I usually do is just wait for 10 mins or so then run the step2.bat manually. Strangely enough my last trial on H990DS seems to always crash/reboot itself on this guide's step 13 / waiting for run step2.bat part; though after it booted back I just continue with clicking step2.bat, and finish the process.

For the static screen, assuming you do everything according to the guide, I think it have something to do with your phone region version and the KDZ file you were in before trying to unlock with DirtySanta. I have this issue with latest H990DS unlock, the phone was for Indonesia region, but I installed KDZ for Singaporean region, which made me can't see stuff with the static screen and had to use LGUP and try another KDZ from the correct region. I think it have something to do with how the modem configure itself.
[LG V20 Guides, News, & Discussion] Sami Devo:
Hi greetings all , recently i bought this device v20.. now want to root to underclock CPU.. but i tried all steps it fails!..my Android security patch is 1 September 2017.. i flashed it android 7.. to get root... i cant find old firmware for my Hd990ds..how to root then?
[LG V20 Guides, News, & Discussion] dextructor:
I hope that you tried to search before you post, but anyways here's my instruction.

Follow everything without exception and your device will be unlocked.
[LG V20 Guides, News, & Discussion] pranciskus2:
LG H990DS(LGH990DS) aka LG V20 Dual - LG-Firmwares.com

LG H990DS download the firmware for free! Detailed installation instruction. Video review of the model and its features. User feedback and latest news.

lg-firmwares.com
[LG V20 Guides, News, & Discussion] Sami Devo:
This website is a waste, they have deleted all files from the server. . My phones region is India.
[LG V20 Guides, News, & Discussion] Sami Devo:
Thanks so much .. i will try it! 😂 I was afraid of the variant ! If the phone goes to bootloop after flash ! Now i know .
[LG V20 Guides, News, & Discussion] pranciskus2:
Region doesn't matter, I have flashed a lot of different regions
[LG V20 Guides, News, & Discussion] Sami Devo:
Showing this now . Firmware is okay.. do i have copy those files to internal storage of phone
[LG V20 Guides, News, & Discussion] Sami Devo:
Everything done and the screen is this
[LG V20 Guides, News, & Discussion] Sami Devo:
A static screen!
[LG V20 Guides, News, & Discussion] dextructor:
Let's make things as clear as possible:

0) I'm not smarter than anyone else

1) This exploit has been tested and worked for probably thousands of users

2) The method has been updated along the way

3) Videos has been made to make it more visually helpful than ever

4) No one it's responsible for your device. If you follow word by word you'll be fine, otherwise you made your own hell, deal with it.

As I made clear on the instructions that I linked on my last post, you should watch the video and take the notes of every command.

Showing this now

The instructions uses many batch scripts to automate the process, and I can't see any of them opened on this screenshot. So again: follow the instructions on the video!

All the files necessary it's linked on my post, download because it's the most appropriated version and it was tested again and again with many machines and Windows versions.

I won't waste one more minute because you can't follow the instructions, if you think that your environment setup, device etc are so unique that prevent you and only you from exploiting your v20 and so many others had succeeded, ok.
[LG V20 Guides, News, & Discussion] Sami Devo:
Am sorry to bother you again.. am having this issue and my phone is unusable now.. i flashed oreo kdz file and naugat rom .. always this screen appears at start up😢. After i clicked wipe data from recovery i am facing this issue..

How can i fix? 😭..
[LG V20 Guides, News, & Discussion] Sami Devo:
Update i have fixed it! With the patched LGUP mode software replaced the patched dll and folders . And a REFURBISH mode flash! Fixed!
[LG V20 Guides, News, & Discussion] dextructor:
If you can't follow simple instructions, you are on your own!

Again, you didn't follow anything as recommended.

So please

stop spamming, and putting nonsense on this thread

because you don't know how to follow the procedures that thousands of others did and didn't have problems.
[LG V20 Guides, News, & Discussion] oleg77:
Hello everyone. A really late reaction, but i was just preparing to root an old H990DS, and some other people could get the same problem.

I had just downloaded dextructor's Bootloader Unlock.7z pack (thanks for collecting this!) and unzipped it on my work PC, and noticed Windows defender (I don't have administrative rights/choice of active protections on that d*mned machine) at once displayed a pop up : 'santa' and 'dirtycow' to be sent to Microsoft :LOL:

Thus you probably also had those two files deleted by your antivirus, and it explains your error
[LG V20 Guides, News, & Discussion] omnimann:
When holding volume down i and insert usb: Welcome to fastboot mode for bootloader unlock.....

When holding volume up and insert usb: Download mode

Am i dead in the water? if i type: "fastboot getvar unlocked" i get bootloader locked
[LG V20 Guides, News, & Discussion] redsky0:
I appear to have bricked my H990DS and as far as I can tell I followed all the steps and everything ran properly. This is coming from complete stock.

I saved an image of my cmd from step 1/3. Flashing TWRP I waited over a minute each time, but for each time I executed the command it said that it successfully completed in around a second (don't have a screencap but it didn't flag any errors).

I start up and after the LG logo the jingle plays but the image looks like a scrambled mess of pixels (see image linked). Where it doesn't crash (blue screen in link below), I can raise / lower volume and it seems to respond properly (but the screen is scrambled).

I can enter Factory Data reset -> Yes -> Yes, it works fine there but once I hit second Yes it scrambles the screen image again. Even (as above)

When I try to enter download mode, I see it show "download mode" but it then instantly scrambles the screen. Running LGUP, it sees unknown device, but I can't proceed once I select it. If I already have LGUP running, it will see the model and then give an error when I select it (see image linked).

http://imgur.com/a/6Ae4D

Any ideas?

As said I am almost certain I followed all instructions to the dot and nothing flagged an error or did anything unexpected according to the instructions.

---

EDIT - So I can get into fastboot without issue. Here is a screencap of me flashing TWRP, apparently with no issue. Also fastboot output which has lock state as "locked" which I assume is the issue?

http://imgur.com/a/r6Qa0

Anything else that I can do to restore? Thanks.
[LG V20 Guides, News, & Discussion] ahlok_hk:
You may try to follow my instruction here:

https://xdaforums.com/showpost.php?p=72716640&postcount=613

Go to fastboot mode and follow from step (P)
[LG V20 Guides, News, & Discussion] redsky0:
THANK YOU!

It seems the trick was not executing to reboot, instead pulling out the battery and IMMEDIATELY going through the Yes -> Yes restore to factory settings.

Edit -

Also through TWRP had to:

Wipe -> Format Data

Wipe -> Advanced / Cache / Dalvik

To get past Secure Boot lockout (the 30/30 tries password LG imposes).
[LG V20 Guides, News, & Discussion] kingnose:
Yep, the first issue you saw happened to me too (the images you posted), and it was because TWRP wasn't flashed properly (yes, it does finish in a second, but it's funky). Wipe -> Format Data removes the device encryption.
[LG V20 Guides, News, & Discussion] redsky0:
I think it's not the time taken that's the issue, it's something that the phone does on boot if you don't immediately enter TWRP through volume down + power button and instead let it boot up normally. From there you can't get into TWRP and have to flash from fastboot again.

I have PMed the OP to change the instructions to remove the reboot command and to instead yank the battery and then directly boot with volume down + power to avoid this issue.