that’s not true in general. The only critical point is relocking the bootloader. As repeatedly mentioned here in the forum, you should always check fastboot flashing get_unlock_abilitybefore relocking the bootloader.
If the answer is 1, it should be possible to relock the bootloader.
If the answer is 0, you should not relock the bootloader.
AFAIK this happens when the the previously installed OS has a security patch that is newer than the OS currently installed.
But I also don’t understand why Fairphone doesn’t communicate this problem more openly or finally fix it. It is not at all ecologically justifiable how many devices have been bricked and rendered unusable due to this problem.
The only thing I have done is make a Paypal complaint (i have paid with paypal).
I have asked them to refund, or give a tool or howto to fix this.
Maybe this will speed up a solution.
Why should this speed up a bug fix?It will not change that your phone is bricked and that it con only be repaired in France. I guess you knew playing around with flashing other systems would void your warranty?
The problem is, at least from my limited understanding at this point, that …
… so the rollback index should be cleared when you switch between locked / unlocked and vice versa. I’ve talked to a Calyx dev in the past, they didn’t get a response out of Fairphone either, and they agreed that it’s broken.
Now, when you switch between ROMs, you should start with a blank slate regarding rollback protection, but you don’t. That leads to it getting triggered if you install the wrong version and lock the bootloader.
Combine that with Fairphone probably resetting OEM unlocking on first boot (I know for a fact CalyxOS does), because that’s the state your phone is in when you buy it and that’s what you should get after installing factory images.
Wrong image + Android booted before locking =
As I said, that’s from my limited understanding, so this might be completely wrong, but since after all this time no one at Fairphone has bothered to clear this up, that’s what I’m going with …
Oh, and in my opinion they shouldn’t charge more than shipping to get bricked phones fixed, it’s a proprietary component, it’s on them to solve the issue.
But unfortunately because the Google bootloader for the Qualcomm Snapdragon uses eFuses on the chip to store this rollback index, it’s physically not possible to reset it, ever. The bootloader causes permanent damage to the CPU whenever an update is installed, by irreversibly blowing those fuses. Fairphone should never have used such a chip that bricks itself, or they should have used a bootloader that doesn’t blow / read them in the first place.
Really it’s up to ME which version of software I want to use on MY phone that I bought. It’s not a rented phone.
It would be great if they could make the phone “unbrickable” by allowing to boot from SD card to install an OS, like the Pinephone / Librem 5 does. Or indeed like any PC/Laptop does.
Only then could they truly say that they are saving phones from landfill.
The AvB specifications I linked above are directly by Google, and they specifically mention that the rollback index should be cleared.
Would be strange for Google to offer a bootloader that violates their own directive …
If you don’t lock your bootloader, none of this matters and you can install as many different operating systems as you want without bricking your phone.
The rollback index only comes into effect once the bootloader is locked.
The rollback protection on the Google Pixel 6, Pixel 6 Pro, and the Pixel 6a is materialized through electronic fuses (eFuses). An eFuse is like a write-once flash. Once you flip those bits by writing something into them, there’s no going back. After “blowing” an eFuse, it’ll stay written with that value forever.
That’s reassuring if this is true. However, what initially worried me was Murena’s website here: https://doc.e.foundation/devices/FP4/install
(see “caution” section in red, and examples)
This section is after you have unlocked the bootloader. There is no mention of re-locking it in the steps up to that point. Yet they still warn that if the anti-rollback is triggered, you will brick your phone.
Well, if that’s the case, that really sucks, but it certainly would explain why it’s not working as it’s supposed to
I’m gonna give Fairphone the benefit of the doubt here, never attribute to malice … etc., but if they don’t explain it / fix it, the outcome is basically the same.
You will, if you trigger it (and OEM unlocking is deactivated), but it’s not active unless you lock the bootloader and if you check fastboot flashing get_unlock_ability before locking it, you can usually unlock it again even if you triggered it.
Beware, that’s the case for the FP4, other phones might even check the rollback index in an unlocked state, it’s up to the manufacturer to decide.
Interesting to see them used in that context. As I understand the article, the eFuse “only” prevents going back to Android 12 when you updated you Pixel phone already to Android 13 once. It doesn’t sound like it affects the rollback protection in general. I personally haven’t tried to go back to Android 12, but I would assume that we had heard already of some cases if this would be impossible.
The variable mentioned in the article isn’t even set in my case (iodéOS with Android 13): (bootloader) version-bootloader:
But as “The Snapdragon processors have a OTP fuse bank region referred to as eFuses (QFPROM) which can be used to store disk encryption keys.”, it doesn’t sound like they would run out of space for single bits quickly. I haven’t found any statements regarding the size, though (searched not too deeply).
I just want to mention that the fact that this whole eFuse thing even exists is unacceptable imo.
It’s “yours to open, yours to keep” and it’s also my goddamn right to install any crappy old Android version I want on it without my phone - that I bought and I am responsible for - destroying itself. If I get hacked then thats my problem, but it’s not Google’s (or anyone else’s) job to patronise me about what I do with my devices.
What you can do is down to the device, and given the complexity of the chips and how they are made for a global audience it’s unrealistic to think you can do what you like.
A ridiculous example is : given the value and cost It still doesn’t toast bread but then my oil filled radiator doesn’t either.
However my old parabolic one bar heater can, be used to boil water and make toast, I can even use the mirror suntan
It seems that had I had toasting in mind I would not have bought a radiator, but I did, well actually I didn’t ~ I use a wood stove for heating and cooking in the winter and solar in the summer, neither of which provide me with toast…
So maybe some mods can be done to the phone or maybe trade in in for one that you can install A4 on.
There are no rights, just privileges and there are limits to what the user has.
I paid for this thing. More than that: I bought a “Fairphone”. The whole “raisin d’etre” of fairphone is to avoid landfill, but if they sell phones which brick themselves, it completely defeats that.
It’s a bit like buying what you thought was a freehold house, only to find out it’s leasehold, and you are beholden to some landlord. And if you paint the walls the wrong colour, they will evict you, and not even refund your money.
Just because it’s a “complicated chip” shouldn’t mean that it has a self-destruct mechanism on it controlled by some third-party… I’m sure you’ve tripped BitLocker on Windows once or twice because you installed a different RAM module or SSD. But your CPU doesn’t fry itself when you do that, it just erases the data (or rather, the encryption keys), which is what you told it to do when you enabled BitLocker. But if someone (say, Apple) sold a PC that rendered itself useless if the wrong software was installed, they would be taken to court. Especially if they had advertised it as “good for the planet” or something…
Yes that’s why I don’t use solicitors for such, I read the detail for weeks.
Don’t misinterpret my arguments for me thinking the FP is a good phone in terms of user experience, I wouldn’t recommend it to anyone.
But I made a choice to support Fair (wages etc.) and there’s no going back on that.
Then why do they make replaceable modules ? I thought the main point was about repairability, and that “fairtrade” was a secondary “value”.
Our core value of longevity is designed directly into our smartphones. We created the Fairphone 3 to last – both in its original design and in making the repair as easy as possible. This made it the only smartphone in the world to be awarded a perfect iFixit score for repairability.
I guess they didn’t create the Fairphone 4 to last…
There’s honesty for you.
I’m sure there are other ways of supporting wages for poor Cambodians/Guyanans/etc than paying them a better wage to go down a mineshaft, though…
The company set out to source fairer traded minerals and then decided a phone would be a good place to use them and promote the idea start and that lead to wages . . .
There’s honesty for you. 
