Database Develop

[HOWTO] Changing Filesystem to F2FS on the Sprint S4

This guide is for the Sprint Galaxy S4 only and as of now it is only compatible with two kernels: KToonsez S4 Kernel 4.4 AOSP (4/17 or later) and PoKernel 1.7 F2FS ONLY Build. This guide CANNOT be used on Touchwiz or Android 4.3 yet. I will update it when and if that becomes possible
*Disclaimer: You are doing this to your phone under your own consent. This is an experimental procedure and may not work on some hardware revisions or on devices where certain conditions are not met. You assume all the risk by flashing any of the software below or changing your filesystems. I am not responsible if your phone does not work based on the method I am describing below. Modify at your own risk.
This guide had to be updated in order to correct misinformation. The guide will follow KT's instructions explicitly until it gets to the formatting of the system partition
***If you want to format your /system partition to F2FS please read that section first as it requires steps to be taken from your currently working AOSP rom!***
First, go this link download the file:TWRP-KT.ALL-IN-1.zip
http://goo.gl/HLz4al
Formatting Data and Cache to F2FS
NOTE: Follow these steps EXACTLY, do NOT add or remove any steps, period!!!!
1. Backup everything from your internal SD to your PC or external SD, since the entire internal SD is going to get wiped out with format!!!!!!!!!!
2. Download the files from the folder that you got these instructions from (Ignore the OLD WAY folder) and SAVE TO THE EXTERNAL SD!!!
3. ONLY DO THIS STEP IF YOU ARE ON AN OLD VERSION OF MY TWRP. Flash TWRP-KT.ALL-IN-1.zip (this is what gives us the ability to format using F2FS)
4. Reboot recovery
5. Go to "Settings" and check the box to force F2FS for data and cache (you can also check the box to include /system partition if you want to convert your ROM's zip to use that too)
6. Go to "Wipe->Advanced" option and wipe the "Cache" partiton
7. Go to "Wipe->Format Data" option (THIS WIPES YOUR ENTIRE INTERNAL SD CARD, all files and folders, all gone so make a backup to your external SD or PC!!!!!!!!!!!!!)
8. This step you have 2 choices:
A. Flash your ROM/gapps to start completely fresh
B. Go to restore option and ONLY restore your "Data" (you can also restore /system if you are doing the f2fs conversion on /system partition too)
9. ONLY DO THIS STEP IF YOU INSTALLED A NEW ROM. Flash my newest kernel (needs to be a kernel dated 05.05.2014 or newer)
10. DONE!!!!!!!!!!!!!
11. KTweaker has a new option under "Tools" screen to "Get Partition info" to double check your work.
Formatting System Partition with F2FS (Required: KT SGS4 Kernel 4/28 or later!)
Steps:
1.) Before doing any F2FS conversion with the above instructions, use your currently working AOSP ROM to grab the AOSP 4.4 Kernel from HERE (4/28 or later only!) and save it to your external memory card
2.) Once it is saved reboot to recovery and install it (Flashing a kernel in TWRP is Install -> Folder where kernel is -> Click KT 4/28 kernel -> Swipe to install -> Clear cache/dalvik -> Main menu -> click advanced -> Fix Permissions -> Reboot to system)
3.) After you are back in your working AOSP ROM with KT 4/28 kernel installed, download the AOSP rom you want to use and save it to your external sd card (You can leave the filename as it is, the program will rename it for you)
4.) Open KTweaker and click "Tools" and at the very bottom choose "F2FS: Convert ROM ZIP"
5.) It will ask you to locate the file, ask if you're sure, and then it will do the conversion; upon completion the zip file that was created will have "-F2FS.zip" at the end of it
6.) Now you can follow the steps above, but when you get to step 9A you will use the "-F2FS.zip" file instead of the standard ROM file
This procedure is necessary because KTweaker changes your favorite ROM to pass the command mkfs.f2fs so that your system partition is formatted to F2FS before the files are installed. I did this myself to verify and it works a treat. One crucial step to remember though is that after you install your F2FS converted ROM you absolutely must install KT's kernel so your phone will boot.
Returning to EXT4
NOTE: Follow these steps EXACTLY, do NOT add or remove any steps, period!!!!
1. Backup everything from your internal SD to your PC or external SD, since the entire internal SD is going to get wiped out with format!!!!!!!!!!
2. Download the files from the folder that you got these instructions from (Ignore the OLD WAY folder) and SAVE TO THE EXTERNAL SD!!!
3. ONLY DO THIS STEP IF YOU ARE ON AN OLD VERSION OF MY TWRP. Flash TWRP-KT.ALL-IN-1.zip (this is what gives us the ability to format using F2FS)
4. Reboot recovery
5. Go to "Settings" and uncheck the box to force F2FS for data and cache (If you checked the box to include /system partition uncheck it first)
6. Go to "Wipe->Advanced" option and wipe the "Cache" partiton
7. Go to "Wipe->Format Data" option (THIS WIPES YOUR ENTIRE INTERNAL SD CARD, all files and folders, all gone so make a backup to your external SD or PC!!!!!!!!!!!!!)
8. This step you have 2 choices:
A. Flash your ROM/gapps to start completely fresh
B. Go to restore option and ONLY restore your "Data" (you can also restore /system if you are doing the f2fs conversion on /system partition too)
9. ONLY DO THIS STEP IF YOU INSTALLED A NEW ROM. Flash my newest kernel (needs to be a kernel dated 05.05.2014 or newer)
10. DONE!!!!!!!!!!!!!
11. KTweaker has a new option under "Tools" screen to "Get Partition info" to double check your work.
FAQ
Q: Why can't I use this on Touchwiz?
A: It has been developed for the most recent Linux kernel 3.8 and has been implemented in kernels built for 4.4.x OSP builds. This isn't to say it cannot be used on Touchwiz, it is a filesystem and as long as there is a kernel that offers support for reading it installed on your device it should theoretically work on your hardware. However, this can be proven/disproven by the devs here and I will update this answer if it cannot be implemented in a backwards fashion.
Q: Are there advantages to using F2FS?
A: It is built and intended for use on flash filesystems which our devices run exclusively. So since it was developed for flash memory there will be a benefit to using it as it matures. However, this does not imply that benchmarks will increase or your whole phone will become more responsive, its intent is to have files be accessed and written more efficiently. It is supposedly also built for the long-term user who does not constantly reformat their devices because it is supposed to handle large amounts of old files and cleaning more effectively that EXT4. Source: https://www.kernel.org/doc/Documentation/filesystems/f2fs.txt
Q: Will this trip Knox?
A: No more than installing a custom recovery would. So if you already had a custom recovery (Read: TWRP, PhilZ, CWM) in place you are safe following this guide. For now of course; I do not know if there will be another iteration of Samsung software that locks down the device futher.
Q: Can I clear Cache and Dalvik to troubleshoot after changing my filesystem?
A: I tried this myself and the answer is yes. As long as you are using the F2FS custom recovery made by KToonsez you can wipe Cache and Dalvik from recovery and it will rebuild your system. Something I did notice is that first boot will stay on the splash screen longer with F2FS than with EXT4. I saw it hang on the splash screen of my Liquid rom for an extra minute before actually booting and showing cache rebuild. **Your Mileage May Vary**
Q: Why isn't the System Partition formatted into F2FS?
A: This can be done now with KTweaker. See section above.
Q: What ROMs can I use with this filesystem?
A: Any 4.4.x rom (most are 4.4.2 now) that is compatible with either KToonsez S4 AOSP kernel or Pokernel 1.7 F2FS Only.
Q: In Advanced Wipe, Preload has been added to the options of things to wipe. Should I?
A: Ktoonsez answer found HERE was that he has never wiped preload. So I suggest against it unless you know what you are doing.
Thanks
Linux, Google, and Samsung (all this neat stuff comes from those communities)
TWRP Team for their custom recovery and its updates
Ktoonsez for his awesome kernel and the modified recoveries
CPA Poke for his awesome kernel that has F2FS support baked in
LuigiBull23 for edits and reminding me to add content
XDA for giving us a place to host experimental phone procedures
The XDA Devs for all the work they do for us with their time
The XDA community for providing feedback and making this a great place to hang out
If I forgot anyone specifically please let me know and I will update this section or any section
Enjoy and let us know how it works on your device!

Great guide my friend!

delete

Thanx great guide
Sent from my SPH-L720 using XDA Premium 4 mobile app

Great guide OP! Always nice to have a thread to link to.
I'm sure it's been talked about but your posts doesn't mention the ramdisk files. They're listed but not talked about. Now I'm somewhat limited myself in understanding everything there is to know about these things but are those files to do with eventually formatting the system partition to f2fs?
May be worth putting a little note in there regarding those files... You know how some folks go flash crazy once in recovery lol
Sent from my SCH-I545 using Tapatalk

Mistertac said:
Great guide OP! Always nice to have a thread to link to.
I'm sure it's been talked about but your posts doesn't mention the ramdisk files. They're listed but not talked about. Now I'm somewhat limited myself in understanding everything there is to know about these things but are those files to do with eventually formatting the system partition to f2fs?
May be worth putting a little note in there regarding those files... You know how some folks go flash crazy once in recovery lol
Sent from my SCH-I545 using Tapatalk
Click to expand...
Click to collapse
Hello again.. Lol
The ramdisk mod is now obsolete as it's already included in the kernel zip, which will automatically determine whether you're still on EXT4 or F2FS and make the required changes to the ramdisk accordingly. So no need to flash anything but the kernel as usual after following the steps.

OK yea I figured it was either to do with what I said or to do with the kernel obviously. Just figured I'd ask anyways
Sent from my SCH-I545 using Tapatalk

I'll be the first to admit that I wasn't entirely sure what the ramdisk files were for. I knew they might have been for advanced users considering they were offered, but not listed in the instructions. I didn't know for sure and I didn't want to use the word "obsolete" because, well, I was so wrong before
I am glad LuigiBull23 jumped in and answered that for us. I'll get it added into the the guide so future users know what they are or are not used for. Keep the questions coming, I love learning about this stuff!

I'll be the first to admit that I wasn't entirely sure what the ramdisk files were for. I knew they might have been for advanced users considering they were offered, but not listed in the instructions. I didn't know for sure and I didn't want to use the word "obsolete" because, well, I was so wrong before
I am glad LuigiBull23 jumped in and answered that for us. I'll get it added into the the guide so future users know what they are or are not used for. Keep the questions coming, I love learning about this stuff!
Click to expand...
Click to collapse
I understand. A lot of people were and still are confused about these files..
In short, during the testing phases of F2FS, KT compiled a separate zip for changes to the ramdisk that in turn would reflect the EXT4/F2FS mount points as a means to avoid possible bootloops and such. It was indeed a success and as a result was included in his kernel.
Now, upon flashing the kernel it is able to determine which partitions are formatted as EXT4 or F2FS and mod the ramdisk accordingly. He only left the files on his server in case he ever needed them again. So they are most definitely OBSOLETE. You certainly wouldn't have gone wrong using the term in this case.

Updated the guide for KT's new all-in-one TWRP recovery that will allow you to switch back and forth between F2FS and EXT4. I used his exact instructions from his guide in all areas except for the system formatting section which I wrote. If you are using his custom TWRP recovery go ahead and grab the new one so you can use it in the future!

F2FS with CM11 Nightly
When I used KTweaker to convert my latest CM 11 nightly, it came back and said that it was done but could not find all the lines to modify. Is this ok?

mwilder817 said:
When I used KTweaker to convert my latest CM 11 nightly, it came back and said that it was done but could not find all the lines to modify. Is this ok?
Click to expand...
Click to collapse
I know it has been forever since you posted this and I apologize for the late answer, but I imagine that if you received that error you got a bad download of CM11. I've personally converted the snapshot and several nightlies of CM11 and they all passed nicely.
So for anyone getting this, if you get a similar error message: Re-download the ROM you are converting

to bad its still not possible with touchwiz, love to use f2fs on a stock rom for my sgs4-lte.
is it possible in the near future that we can use f2fs on those devices with a Samsung stock rom, using another kernel is no problem.
or is this hard to tell ?

Hello, I've been trying to use this to change my filesystem because I'm coming from CM12 and I'm trying to flash a GPE rom on my S4. But after flashing I am rebooting straight to recovery. Also I'm using the latest TWRP.

RealMikeyTaylor said:
Hello, I've been trying to use this to change my filesystem because I'm coming from CM12 and I'm trying to flash a GPE rom on my S4. But after flashing I am rebooting straight to recovery. Also I'm using the latest TWRP.
Click to expand...
Click to collapse
Make sure you are using a version of TWRP that support F2FS. I don't think the standard issue TWRP does. @AntaresOne has one that does support F2FS and is based on the latest version (2.8.3.0). That's the one I use. Of course, I'm hooked on his CM12 ROM as well. He does really good work!!

mwilder817 said:
Make sure you are using a version of TWRP that support F2FS. I don't think the standard issue TWRP does. @AntaresOne has one that does support F2FS and is based on the latest version (2.8.3.0). That's the one I use. Of course, I'm hooked on his CM12 ROM as well. He does really good work!!
Click to expand...
Click to collapse
But doesn't it have to be in EXT4 for it to work for a GPE ROM?

RealMikeyTaylor said:
But doesn't it have to be in EXT4 for it to work for a GPE ROM?
Click to expand...
Click to collapse
You are probably right. I haven't tried the GPE ROM yet.
Sent from my SPH-L720 using XDA Free mobile app

RealMikeyTaylor said:
But doesn't it have to be in EXT4 for it to work for a GPE ROM?
Click to expand...
Click to collapse
Yup gpe uses ext4 on all partitions because it uses tw framework

Galaxy S8 boot loop after trying to install an older version of Magisk

First, I should point out that I'm just a user, not a developer or hacker. I'm posting this because I don't know where else to ask for help.
This will most likely look like the post of an idiot. But, oh, well, I did manage to mess up my phone, which means I am an idiot. So here it goes: I had 16.0 installed and I tried to install 14.0 from TWRP recovery mode. Basically, Magisk hide wasn't working very well so I wanted to see if it worked with an older version. Now my phone is stuck in a boot loop. It just shows "Samsung Galaxy S8 powered by Android" then restarts. I can boot into TWRP and connect the phone to the PC to access the storage this way, but I can't boot into the OS. Is there any way I can fix this, preferably without losing my data?
I tried flashing the official uninstaller, but I get the message "Update process ended with ERROR: 1"
Here's what the log says about the uninstaller:
Mounting /system, /vendor
-Device platform: arm64
cp: can't stat '/dev/tmp/install/arm64/.': No such file or directory
! Cannot find /data/adb/magisk
Updater process ended with ERROR: 1
I:Install took 1 second(s).
Error installing zip file '/sdcard/Download/Magisk-uninstaller-20180429.zip'
Updating partition details...
I: Data backup size is 32943MB, free: 2620MB.
I:Unable to mount '/usb-otg'
I:Actual block device: '', current file system: 'vfat'
...done
I:Set page: 'flash_done'
I: operation_end - status=1
I looked at the contents of the zip on my computer, and it doesn't have an arm64 folder. So the uninstaller doesn't work on arm64 phones?
Update: I managed to uninstall Magisk using a compatible uninstaller, but the phone still doesn't boot into the OS.
Update 2: if I have to flash the stock ROM, I'm planning to do the next thing: back up my data partition to an external hard drive with TWRP. After I flash the ROM and wipe everything, I want to reinstall TWRP and restore that backup. Would this cause any issues?

Yes, there's an issue on 64-bit devices with the latest available uninstaller. Use the next to last, here: https://github.com/topjohnwu/Magisk/releases/download/v16.3/Magisk-uninstaller-20180328.zip

Thanks. I've just left home and I'll be away for two days. I didn't take the S8 with me, so I won't be able to try any more fixes until Sunday. But I'll check then and update my post if there are any more issues.

Didgeridoohan said:
Yes, there's an issue on 64-bit devices with the latest available uninstaller. Use the next to last, here:
Click to expand...
Click to collapse
I managed to uninstall Magisk with that zip, but the phone still doesn't boot into Android.

vladone97 said:
I managed to uninstall Magisk with that zip, but the phone still doesn't boot into Android.
Click to expand...
Click to collapse
In that case, restoring the stock boot image manually might work. If not, a complete restoration of your device's stock setup might be necessary.
Your device's forum is likely the best place to get further help.

Didgeridoohan said:
In that case, restoring the stock boot image manually might work. If not, a complete restoration of your device's stock setup might be necessary.
Your device's forum is likely the best place to get further help.
Click to expand...
Click to collapse
I tried flashing the stock boot image and it still doesn't work. Stock restoration it is then.

Didgeridoohan said:
In that case, restoring the stock boot image manually might work. If not, a complete restoration of your device's stock setup might be necessary.
Your device's forum is likely the best place to get further help.
Click to expand...
Click to collapse
One more question, though: I backed up my data partition to an external hard drive with TWRP. After I flash the stock ROM and wipe my data, I want to reinstall TWRP and restore that backup. Would this work or would it cause problems?

vladone97 said:
One more question, though: I backed up my data partition to an external hard drive with TWRP. After I flash the stock ROM and wipe my data, I want to reinstall TWRP and restore that backup. Would this work or would it cause problems?
Click to expand...
Click to collapse
If you get your device up and running after the wipe and reinstall, you could always try restoring the backup. If it works, it works, and if it doesn't you can just wipe /data again.

Didgeridoohan said:
If you get your device up and running after the wipe and reinstall, you could always try restoring the backup. If it works, it works, and if it doesn't you can just wipe /data again.
Click to expand...
Click to collapse
Is there any other partition I should back up? That is, aside from the internal storage, which I've already taken care of.

vladone97 said:
Is there any other partition I should back up? That is, aside from the internal storage, which I've already taken care of.
Click to expand...
Click to collapse
Not if you're flashing back to stock anyways. Sounds like something is borked anyways so restoring anything might cause problems (including data). I would just start over. It's just data. Apps can be re installed. Contacts re sync.
I would start fresh, make sure it boots, make a full backup, then try restoring only data. Remember that /data may contain some of your old magisk stuff that may have added to the problem. So do that at your own risk. What data could be worth all that hassle?
Try to think of it like, if that phone got smashed, and you got a free replacement tomorrow. You'd survive right? Even without that data?
And definitely don't try to flash a magisk version that old over one that new one again.

vladone97 said:
Is there any other partition I should back up? That is, aside from the internal storage, which I've already taken care of.
Click to expand...
Click to collapse
Good advice by @madbat99.
Personally I only ever keep TWRP backups of the devices I test stuff on. But then I do a full backup of the device to have an easy way to get back to the setup I want.
On my everyday device I only keep a backup of the internal storage and messages (Signal). It's so easy to restore apps and other stuff anyway, so I don't really bother...

Didgeridoohan said:
Good advice by @madbat99.
Personally I only ever keep TWRP backups of the devices I test stuff on. But then I do a full backup of the device to have an easy way to get back to the setup I want.
On my everyday device I only keep a backup of the internal storage and messages (Signal). It's so easy to restore apps and other stuff anyway, so I don't really bother...
Click to expand...
Click to collapse
I did all that, but Magisk 19.1 still doesn't work. Some older versions work though. I tried Magisk 18.0, 18.0, 19.0 and 19.1. Only 18.0 and 18.1 worked. So I'm assuming there's a problem with the newer versions of Magisk?

System storage taking up huge space

Is this normal?

10-12GB nothing unusual as far as I'm aware

reg66 said:
10-12GB nothing unusual as far as I'm aware
Click to expand...
Click to collapse
Thanks for the response. Can you tell me what are the things included in the system storage? Thanks in advance.

No! is the short answer! But comparing my mi pad 4, mi 9 and even old banger of a galaxy S4 has a system of 6+GB. I'm currently using Ros and that's using nearly 13+GB.
I don't know what or why, but for example, when you install Windows 7 or 10, the file or disc size might 3-4GB but once decompressed, installed with all packages etc, the installation easily takes a LOT more than that - can't remember off hand tho exactly how much! I'd guess at 20oddGB at least, but could easily be off on that one.
Why don't you google it!

You might want to try using the built in cleaner in the security app. It can wipe app and system cache that can easily take 3-5 gigs of memory and also delete unneeded packages (the original zip files) used for system updates.
Cleaner apps that you download from the Play Store are useless since they don't have root access but the built-in cleaner on the MI 9 is a system app so it doesn't need root access. It is genuinely useful but it can also delete stuff you want to keep (like your music artwork) so I always look at what it plans to clean before running it.

zydalili said:
Is this normal?
Click to expand...
Click to collapse
Yes

zydalili said:
Is this normal?
Click to expand...
Click to collapse
Yes the system will take alot of space.
But you can reduce its size by removing all but one of you redundant local backups. Next clear your cache and remove any potential encrypted data that you are not using. Sometimes you can end up with a batch of unused encrypted data if moving from a the beta EU weekly to Global stable or from Mi-Globe custom to either EU weekly or global stable.
If rooted you can keep this from happening by flashing DM No verity after flashing something new via TWRP or by flashing the boot.image from the rom that the encrypted date is originally from. One certain way to remove it is to do a factory reset or formating user data if you have an unlocked bootloader and installed TWRP.
If you are still on stock and you still have a locked bootloader, you can just use the internal cleaning program or a program such as SD Maid which is an awesome program and very much worth buying the pro version

tsongming said:
Yes the system will take alot of space.
But you can reduce its size by removing all but one of you redundant local backups. Next clear your cache and remove any potential encrypted data that you are not using. Sometimes you can end up with a batch of unused encrypted data if moving from a the beta EU weekly to Global stable or from Mi-Globe custom to either EU weekly or global stable.
If rooted you can keep this from happening by flashing DM No verity after flashing something new via TWRP or by flashing the boot.image from the rom that the encrypted date is originally from. One certain way to remove it is to do a factory reset or formating user data if you have an unlocked bootloader and installed TWRP.
If you are still on stock and you still have a locked bootloader, you can just use the internal cleaning program or a program such as SD Maid which is an awesome program and very much worth buying the pro version
Click to expand...
Click to collapse
I see no way to delete the cache partition in recovery mode (standard) as is found on other brands. Is there an option hidden somewhere?

gerhard_wa said:
I see no way to delete the cache partition in recovery mode (standard) as is found on other brands. Is there an option hidden somewhere?
Click to expand...
Click to collapse
You need to be using twrp, I take it ur on Stock

reg66 said:
You need to be using twrp, I take it ur on Stock
Click to expand...
Click to collapse
Yes I´m on the standard EEA firmware and have no intention to either unlock the bootloader nor to flash twrp and a custom rom. Thanks for the info!

The “descriptive explanation” you gave still doesn´t make a reference on how to wipe the cache partition. The cleaning app of the system doesn´t fix it and neither do SD Maid. I have since discovered that it isn’t possible to do it without unlocked bootloader and twrp, and so I will leave it at that.

gerhard_wa said:
The “descriptive explanation” you gave still doesn´t make a reference on how to wipe the cache partition. The cleaning app of the system doesn´t fix it and neither do SD Maid. I have since discovered that it isn’t possible to do it without unlocked bootloader and twrp, and so I will leave it at that.
Click to expand...
Click to collapse
You are on stock, you are overthinking the extra space. If it's not because of redundant local back ups. Its just temporary cache files. I already recommended using SD Maid and I suggested what to do if you are on stock. Otherwise your experience would be much better with the bootloader unlocked and rooted. But as you have stated for some reason you don't want to do that.
Here's a very helpful tip: If someone takes their time to give you more than just a one sentence answer, use common courtesy and click thanks. It's the only motivation for someone to spend their time helping you resolve your issue.

Partition A
Partition B

guys, have a look at the last few posts, they smell better now, huh?
I`d say, be nice to each other, isn`t hard at all, we`re not dealing with money here, is just a lifeless gadget that you may sell it tomorrow, isn`t worth getting into "philosophical" debates
have fun and enjoy the forums!

Device sold, onto Mi 9 now... ?

badaas said:
Partition A
Partition B
Click to expand...
Click to collapse
No, Partition A only on Mi9. No seamless system update on this device.

Can you explain that more clearer on how to root. I formatted my 32gb sdcard as internal storage and it's system storage are 21gb.

Sus

[GUIDE] ROM flashing the easy way

We all know flashing ROMs got a lot more complicated with the advent of A/B partitions.
This is not my work, the aim here is only to highlight a process which simplifies the task.
Original post on the OnePlus 6 forum can be found here:
https://forum.xda-developers.com/oneplus-6/how-to/script-copy-oxygenos-base-partitions-to-t4097979
It makes use of a script which copies the flashed firmware to both slots without having to reboot recovery and do it a second time. Also by not having to reboot recovery you avoid the issue where internal storage becomes unreadable.
Credit for this goes to:
LineageOS @erfanoabdi @filipepferraz @Prakyy @drpradsms
Download by prakky (hit the thanks button on his post below):
https://androidfilehost.com/?fid=8889791610682890605
The following posts detail it's usage which you follow at your own risk.

Clean Flashing a new ROM
Disable lockscreen security
Boot TWRP 3.4+
1) Flash latest OOS
2) Flash ROM
3) Flash TWRP installer
4) Flash Finalize.zip
5) Format data; type 'yes' (backup as this wipes phone)
6) Boot System
Reboot recovery to flash additional zips.

Updating OOS base whilst on a custom ROM
Boot TWRP 3.4+
1) Flash latest OOS
2) Flash ROM
3) Flash TWRP installer
4) Flash Finalize.zip
5) Boot System
Reboot recovery to flash additional zips.

Updating a custom ROM (nothing fancy here)
Boot TWRP 3.4+
1) Flash ROM
2) Flash TWRP installer
3) Boot System
Reboot recovery to flash additional zips.

Reverting to OOS
WARNING I've yet to test this!
Boot TWRP 3.4+
1) Flash latest OOS
2) Flash Finalize.zip
3) Format data; type 'yes' (backup as this wipes phone)
4) Boot System
Note: this will revert you to stock recovery as well.

Tip:
Chain install the zips by selecting 'Add more Zips' after selecting the first zip.
Only 'Swipe to confirm Flash' once all zips have been queued.
I recommend numbering the zips in the order they need flashed.

Note: this issue is now resolved as of 09/08/20 as per https://forum.xda-developers.com/oneplus-6t/how-to/guide-rom-flashing-easy-t4143701/post83241857
As a side note and given that I show an OmniROM zip in the previous screenshots here's a fix required for flashing OmniROM.
I use Mixplorer to do the following.
1) Open the OmniROM weekly zip
2) Navigate to folder shown
3) Open metadata
4) Edit oneplus6t to OnePlus6T
5) Save metadata
OmniROM will now flash successfully in TWRP.

Nice post! Don't mean to be rude but is kinda redundant as my thread already existed: https://forum.xda-developers.com/oneplus-6/how-to/script-copy-oxygenos-base-partitions-to-t4097979

Prakyy said:
Nice post! Don't mean to be rude but is kinda redundant as my thread already existed: https://forum.xda-developers.com/oneplus-6/how-to/script-copy-oxygenos-base-partitions-to-t4097979
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Didn't know your post existed. Only learnt about the method on Pixen OS thread which uses it and gives you credit as did I. A lot of people only look in their own phone forum. If you don't mind I'll leave this thread open. However if you aren't happy I'll ask a mod to close it.

Deleted. Think maybe I'm getting altimeters. ?

Prakyy said:
Nice post! Don't mean to be rude but is kinda redundant as my thread already existed: https://forum.xda-developers.com/oneplus-6/how-to/script-copy-oxygenos-base-partitions-to-t4097979
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Edited first post to make it clearer this is your work.

mitchst2 said:
Didn't know your post existed. Only learnt about the method on Pixen OS thread which uses it and gives you credit as did I. A lot of people only look in their own phone forum. If you don't mind I'll leave this thread open. However if you aren't happy I'll ask a mod to close it.
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You can keep it open ofc I don't mind.
However, yes, many people only see in their device's forums but since this script will work w/ any A/B device, is there a forum I could post in so that all device owners can see it??

Prakyy said:
You can keep it open ofc I don't mind.
However, yes, many people only see in their device's forums but since this script will work w/ any A/B device, is there a forum I could post in so that all device owners can see it??
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Good question.
Is 'Android Development and Hacking / General' the right place? There are some all device guides with a lot of views in there.
https://forum.xda-developers.com/android/general

mitchst2 said:
As a side note and given that I show an OmniROM zip in the previous screenshots here's a fix required for flashing OmniROM.
I use Mixplorer to do the following.
1) Open the OmniROM weekly zip
2) Navigate to folder shown
3) Open metadata
4) Edit oneplus6t to OnePlus6T
5) Save metadata
OmniROM will now flash successfully in TWRP.
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As of 09/08/20 build and this commit all is well with OMNI and TWRP again. No need to edit the ROM zip anymore.

Is there a proper way to switch from one custom rom to another without formatting the data? Encryption and A/B made the custom rom game so crazy and time taking now. Or maybe I lost track of things. I could always take a backup of storage on laptop but the backups are very huge, mostly 80gb+ and takes forever while backing up whatsapp databases with images thumbnails and all.

brajesh.sharma87 said:
Is there a proper way to switch from one custom rom to another without formatting the data? Encryption and A/B made the custom rom game so crazy and time taking now. Or maybe I lost track of things. I could always take a backup of storage on laptop but the backups are very huge, mostly 80gb+ and takes forever while backing up whatsapp databases with images thumbnails and all.
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No when switching ROM formatting data will be necessary. Not used it myself but others recommend Migrate to restore apps and data.

I was looking for a way to backup current rom using twrp, test a rom and then be back on the original rom with a twrp restore. If anyone finds a way to do this without format data, pls let me know.

brajesh.sharma87 said:
I was looking for a way to backup current rom using twrp, test a rom and then be back on the original rom with a twrp restore. If anyone finds a way to do this without format data, pls let me know.
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I just restored PiXeN from AOSPA on 6t device and had no issues and I did NOT format my data or do anything but let TWRP do it's restore then rebooted system.. Just backup your system, data and boot partitions and restore them then reboot system. I didn't encrypt my backup using a pw in recovery. I also use magisk canary latest and the themed TWRP recovery 3.4.0-v1 from EvoX rom that acuicultor compiles and morphine1 themes. I've not restored yet using any other TWRP so not sure what works and what doesn't as far as that goes but the themed recovery works for me.
**Formatting data is unavoidable when installing an AOSP custom rom coming from stock OOS rom.
Edit

flash713 said:
I just restored PiXeN from AOSPA on 6t device and had no issues and I did NOT format my data or do anything but let TWRP do it's restore then rebooted system.. Just backup your system, data and boot partitions and restore them then reboot system. I didn't encrypt my backup using a pw in recovery. I also use magisk canary latest and the themed TWRP recovery 3.4.0-v1 from EvoX rom that acuicultor compiles and morphine1 themes. I've not restored yet using any other TWRP so not sure what works and what doesn't as far as that goes but the themed recovery works for me.
**Formatting data is unavoidable when installing an AOSP custom rom coming from stock OOS rom.
Edit
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I had to mandatory format data when I wanted to move from evolution x to aospa.

brajesh.sharma87 said:
I had to mandatory format data when I wanted to move from evolution x to aospa.
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And I've also had to format data before as well but not lately. Could it be because I format both slots coming from OOS or because I use Canary Magisk or the recovery I use.. No idea but next time you are on EvoX backup system, data and boot and try and restore it using that recovery that comes with EvoX and see what happens. These last few weeks I've stayed on AOSiP and PixeN and I flashed Omni once I think but restoring from AOSPA to Pixen was flawless for me and also restoring Pixen to Pixen was also fine, which I do because I always mess around with sound mods.... I'm on AOSiP now and soon as I get more charge on my phone I'm going to try and restore to something I have a backup already made on one of my USB drives and I'll edit this post and report what the outcome is...

Internal storage encrypted despite all 3 methods. Please help!

Hi!
My only encounter with rooting was several years back when it used to be a simple affair (one click rooting app based on exploits like framaroot etc), so please bear with me.
I'm on Stock Oreo 8.1 (Patch 1 Aug 2019) Sanders 1804 (India) version. I've followed various guides and have been successful in flashing TWRP 3.4.0 (Official Sanders version) and Magisk 20.4. But everytime the phone is rebooted, TWRP can't mount internal storage and shows 0mb.
I tried all three methods I could find:
1. dm-verity zip flashing - Log said fstab not found. Searched and found that from Oreo, Android's encryption approach has been changed. I couldn't make much sense out of those, though.
2. Manually replacing the `forceencrypt` to `encryptable` then flash stock recovery and format data. Didn't work.
3. Formatting data right after TWRP is flashed. Didn't work either.
The maximum it works is for one time when I can connect the device to laptop to add some zips to it to flash. It doesn't make sense to wipe the data when it's the data only that we want to back!
My purpose is to make flashable zip (nandroid) to revert to if anything goes wrong. It was phone's wifi frequent disconnection (or connected but no internet) issue which forced me to try root. I'm not much interested in new ROMs and am fine with stock itself but need a backup of all apps with data etc. Also, I couldn't understand clearly the FAQ on TWRP website that says TWRP doesn't backup internal storage but backup data. As I don't use SdCard, the internal storage is mounted in /sdcard folder only
I'll really appreciate if someone can help me.
Thanks

Found solution from a helpful guy in a Telegram group.
1. Use ONLY attached zip/img files and follow exact same order.
2. Flash TWRP, reboot to recovery
3. In Wipe section, choose Format data, type YES and confirm. Reboot to recovery again.
4. Flash DM-Verity-ForceEncrypt.zip file. Flash Magisk.zip file. Reboot to recovery.
5. (Optional) Make a backup if you want or Reboot to system. Done!
https://drive.google.com/drive/folders/1h8wb78wLH5_VBmkhjpDjyPyDbUG9ZBV4?usp=sharing