[Google Pixel 6 Pro] Lughnasadh:
When I say "These corruption issue seem to come out of nowhere...", I was specifically referring to what the user I was replying to was experiencing. They said all they did was remove the -w from the flash-all.bat file and updated. They then got into a bootloop with the corruption message. There does not appear to be any user error in this instance and it doesn't appear that Google messed up the April factory image thus their problem seemingly "came out of nowhere". In other words, it doesn't appear the user did anything wrong, yet still experienced a problem that would not normally be expected, thus "coming out of nowhere".

There have been plenty of instances in a variety of situations, including just updating via flash-all, updating via OTA delta, updating via OTA "Install to Inactive Slot", updating to certain Canary versions of Magisk, flashing kernels on certain versions of Magisk, etc., where people have still experienced the corrupt message post Canary 23016 (the version that fixed the initial problem of not being able to boot with a Magisk-patched boot image in December). Even when people have followed updated OPs and have been careful these issues have sometimes occurred. Just look through the threads. Of course, that's not to say that if you don't disable verity and verification you will have problems. There are plenty of instances, even the majority of instances, where people have not disabled those flags and have had no problems. However, there are plenty of examples where people still continue to get the corruption message to this day, for whatever reason, as evidence by the experience of the user I was replying to.

And of course not disabling Magisk mods before updating has been a problem for people. And of course sometimes people aren't careful when flashing. But this does not account for all the corruption errors people have experienced. As stated above, there have been a number of different scenarios where people have ran into the corruption message that have nothing to do with not being careful or not disabling Magisk mods.

Here's just a few quotes from the developer of the Kirisakura kernel posted well after Canary 23016 was released:

"Some users ran into the device is corrupted message for a quite a while now. It not only happens when flashing a kernel.zip, but in the end it seems related to a problem with verity/vbmeta and magisk. I think it´s related to keeping verity/verification enabled (not disabling the vbmeta flags via fastboot) and something just gets scrambled. Check the forums there are a few threads with plenty of cases."

"But given all the issues some people run into, when they end up with the device is corrupted message (seems also to happen when flashing/updating just factory images without the involvement of anything else, at least what I saw in the guide threads) there still seems to be something wonky."

"The issues some users are getting unfortunately have nothing to do with the kernel. It´s a mixture of google having some problems with the corruption thingy themselves as they revealed in the patchnotes (March 2022) and the other issues are due to magisk canary being experimental canary builds."

Also, if you glance through the Pixel 6 series threads where people have had the corruption message, almost invariably the people that do get this corruption message have not kept verity and verification disabled. The above kernel developer (as well as myself) continues to keep verity and verification disabled to this day because of the continuing problems that those who don't keep it disabled may run in to.

Furthermore, the corruption message does appear to relate to a dm-verity corruption.

dm-verity corruption​

Example RED eio screen:

Show a RED eio screen if a valid version of Android is found and the device is currently in the eio dm-verity mode

Boot Flow | Android Open Source Project

source.android.com

I'll also give you a couple of examples where disabling verity and verification have helped prevent getting the corruption message:

1. When Canary 24303 was released, many, if not all, people using a custom kernel and updated to this Canary version couldn't boot and got the corruption message. Almost invariably it was only those people who had verity and verification disabled that did not get the corruption message. Those who had verity and verification enabled did get the corruption message.

2. When Canary 24304 was released many people got bootloops and experienced the corruption message while having multiple modules installed, including audio mods. Again, almost invariably those who had verity and verification disabled did not get the corruption message.

The above problems were fixed in Canary 24305.

In fact, I know exactly why I personally keep verity and verification disabled. When people run into the corruption problem, often times the only way to make it disappear is to do a full wipe or clean flash. There have been other instances where people have been able to get rid of that message, such as reverting to an older monthly build, reverting to an older boot image and then updating that boot image, and on occasion just waiting for the next monthly build and then updating. How you got the corrupt message also appears to be relevant in the manner in which you make it disappear. But just going through the threads you'll see that in many, many instances the only way people could get rid of that corruption messages was to do a full wipe or clean flash.

Thus, the reason I personally keep verity and verification disabled is to prevent getting the corruption message in the first place, thus avoiding having to do the steps described above to get rid of the message. And I've described 2 of the situations above where having these flags disabled did in fact help to prevent getting the corruption message. If you go through the threads you'll also see that in almost every instance where people were getting the corruption message, those in the same situation who had the flags disabled did not get the corruption message.

And to my knowledge, I have not seen any issues from anyone I know who continue to keep these flags disabled. Maybe you know of instances where keeping these flags disabled have caused issues? If so, I would appreciate you pointing these out to me.

Again, I'm not saying that disabling those flags is needed, but it can help to prevent getting the corruption message and avoiding the steps described above to get rid of that message. So while you think you are saving me from "headaches down the road", I have actually prevented headaches for myself by keeping verity and verification disabled. To each their own...