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Luckily there's still postmarketOS what accomplishes the same thing by replacing android on android phones with an Alpine Linux install.
It doesn't achieve the same thing. Linux on DeX had full driver support because it was running on top of Android. postmarketOS has to play catch up.
driver support for what hardware on the device specifically? Is it not open-source? aka can it not be backported?
Linux on DeX didn't have to worry about drivers at all, because it was running in a container on an Android system. Like how your USB mouse will work on an operating system that only has PS/2 support in a virtual machine.
Android's driver APIs and userland implementation are nonstandard. They have their own libc (bionic) and their own linker. Vendors supply binary blobs for many drivers (RIL, graphics, etc.).

These drivers need a series of compatibility shims to work with "normal Linux," on both sides of the driver API.

The Kernel <-> Driver interface needs to be backported to Android's non-mainline HAL, usually using Halium. The driver <-> userspace API needs to be implemented, for example by xf86-video-hwcomposer or libhybris-libwayland-egl. Finally, the blob needs a libc shim to work with normal libc (libhybris itself).

https://wiki.postmarketos.org/wiki/Hybris

I like to point out that most devices don't use hybris on postmarketOS
Until pmOS can make a call, it doesn't.

I love the postmarketOS initiative but right now it's very much a bare-bones project. The installation process is troublesome, hardware support is very limited and desktop environments work partially if at all. Phosh development is looking good but it's certainly not finished.

As of now, I would certainly not advertise it as a Dex replacement.

The same thing?

I did some reading and it looks like the devices it runs on are ancient.

Linux on Dex ran on a Note 9 which has either 6 or 8gb of RAM.

With HDMI output it's possible to run visual studio code and it's very usable.

Even possible to run a Dev server.

And whilst I'm doing this using a monitor, keyboard and mouse, Android is still available on the device and I can use Spotify, send text messages and make phone calls.

Postmarket OS looks like at best a dual boot setup, running on ancient hardware and very alpha.

This actually is/was really good.

On my note 9 I can open a shell. Or with HDMI get a Ubuntu desktop.

Any ideas what Google changed in Android 10 to break compatibility?

> Any ideas what Google changed in Android 10 to break compatibility?

Samsung's desire to continue developing the feature

Most likely Samsung got tired to keep their fork, as regular Android doesn't expose Linux in such way that DeX is possible.

For regular Android, the fact that Linux is being used is mostly transparent for userspace.

Could have to do with the fact that Google implemented new SELinux policies preventing the running of binaries from an app's data directory. Any binaries you run on Android 10 or later must be bundled in the apk and are read only on the device.

I think Termux uses proot to get around this, so it still works (for now). If this is indeed the reason, Samsung probably just said "fuck this shit".

Expect Google to push out a Fuchsia-based Android whose kernel won't allow the proot hack sometime in the next few years. Like it or not, the closed ecosystem of iOS provides more value to end users, and Google wants to bring those benefits to Android.

> Could have to do with the fact that Google implemented new SELinux policies preventing the running of binaries from an app's data directory. Any binaries you run on Android 10 or later must be bundled in the apk and are read only on the device.

Does this mean the title should read something like "Due to Android 10 update, Linux on DeX will now require a jailbreak whereas it did not before"?

Like Samsung is going to ever admit that jailbreaks exist. They'd sooner cancel the app and uninstall it from everyone's device.
More likely is that they decided it was too much an effort for too little gain.

Samsung always appeared to do little to discourage "opening up" their devices, unlike for example HTC and other Qualcomm based ones.

I beg to differ. The US Notes and other flagships are not unlockable. I believe the only option was to get the Puerto Rican version which had US frequencies but the Exynos chips.
The US models use Qualcomm chips and are close to completely different models. That's why I mentioned Qualcomm, as the issues tended to be related to those, and I suspect the use of Qualcomm chips might be related to them having such annoying process for unlocking - and the greedy US carriers requiring that.
No, it means that we should probably stop believe completely unsubstantiated claims based on the sole fact that its trendy to hate on Google.
"Like it or not, the closed ecosystem of iOS provides more value to end users"

Is there any "official" proof for this statement? To me closed ecosystem of iOs (and semi closed Android for that matter) look truly pathetic comparatively to what I have on Windows/Linux desktop

There SELinux change & its impact on Termux is discussed in quite a detail here: https://github.com/termux/termux-app/issues/1072
Huh? What does that have to do with this? I was countering the point about closed system "being better" for users. Not the technical merits of control
That is an interesting discussion.

Summary: the conundrum Google finds themselves in is they want all code run by the user in plain sight: signed by the developer and inspectable by their anti malware tools. It's not difficult to see why they want this.

The stand out counter example is Browsers downloading and running javascript, which is unseen by them, unsigned and worst of all for them utterly impossible to prevent entirely. So in Termux's case it's always going to be near impossible to block interpreted languages like python from running.

The interesting special case is what they called mmap(PROT_EXEC), possibly better called mmap(PROT_EXEC|PROT_WRITE). In other words, the ability to write and execute create code on the fly. JIT's can't work well without it, so without it Javascript is always going to run like a dog. But with it is is always possible to load an ELF binary yourself in user space, bypassing the kernel entirely. Termux could always replace the libc exec() with something that did it that way.

So it looks to me like this is all just re-arranging the deck chairs. Ultimately Google can't use technical measures to prevent any malicious app from running any code they damned well please. Their attempts to accomplish the impossible won't help the malware problem, but does make like difficult for innocent apps like termux.

As others have said this have said, this has nothing to do with Samsung killing Linux on Dex. Unlike Termux, they have to power to turn it all off.

Your ability to tweak, customize and rice your setup is not what standard users want.

They want it to just work and be secure. iOS has this figured out hands down.

"They want it to just work and be secure". - Says you, not "they". "Them" standard users do not even know what secure is.

As for "just work" - nothing "just works" in the software business. It is snake oil

You've somehow managed to be even more dismissive than my own earlier comment. It's not a healthy way to view this industry.
"Not healthy way" - this is interesting. I think that the industry is in a business of making money. They do not give rat's a$$ about what is best for customer. What they do instead is they try to "educate" said customer to swallow their hook, line and sinker. Apple is very successful in this business.
> Like it or not, the closed ecosystem of iOS provides more value to end users, and Google wants to bring those benefits to Android.

I doubt this is true for everyone.

The closed ecosystem brings more leverage to Apple and a different value proposition for the users - not better or worse, different.

If you're happy with the freedom the OS vendor gives you, then the sandbox is a win because it eliminates a possible vector of harm. If you're not happy with the set of solutions, and want to put together your own, then you need a way out of the playpen. Different, not better or worse.

>> Like it or not, the closed ecosystem of iOS provides more value to end users

Am I correct to assume that you mean direct updates, and/or security (from hackers, states, and, in a sense, hardware vendors themselves)?

Wow, this sounds awful. Thanks for warning me not to upgrade to Android 10.
Purposefully not updating software on a networked machine is rarely the clever answer. Switching from Android to something else might be, depending on what the something else is.
I'm not being clever, I'm just being practical. Feel free to throw suggestions for how I can run Linux binaries on my phone and I'll happily consider them.
That's really hard to do in the general case, since I know nothing about your phone or how locked down it is (other than that it presumably runs Android 9). Honestly, support is spotty and it's usually easier to purposefully buy a device that's well supported for some method than it is to start with whatever device you have in your pocket and go from there. That said, you might get lucky and find a method for your device by searching the XDA Developers Forum for it. On that forum you can also find multiple bootloader projects that each support different devices to varying degrees.
SailfishOS comes to mind. But it's not on par with Android (yet, or ever), however it's Linux, the real thing.

I learned about it in the AskNoahShow ep.144 titled "SailfishOS" [1], you might wanna check it out.

It runs notably on open-source phones from Sony. You can bet that's my next toy!

[1]: https://podcast.asknoahshow.com/144

I bought a Sony Xperia XA2 Plus for this express purpose.

A couple of things:

fastboot oem unlock is a one way trip, it blows some kind of fuse and you can never relock the bootloader. While I give Sony lots of points for having a page showing where the UART is in their phones, they lose all of those points for deciding that unlocked devices can no longer get OTA updates, even when reflashed to a stock ROM.

Sailfish was really, really janky when I tried it, I couldn't even turn on developer mode without signing in to a Jolla account, then it hung for at least 5 minutes trying to enable the developer mode.

For the XA2 Ultra, there's also no LineageOS build.

Thanks a lot for the feedback, I'll definitely keep it in mind!

My idea and recommendation, taking a cue from Noah Chelliah (link above), is basically to have two smartphones — 1 dedicated to SailfishOS, and 1 "fallback" on Android for everything else. Then see from there.

I'm pretty sure the Xperia that GP mentioned is supported by both MultiROM and Sailfish, so if you're buying devices specifically for this purpose you should be able to dualboot both Sailfish your Android fallback on that one device (among others you could choose from).
Oh? This sounds awesome! I'm really not a phone person, barely use it —PC all the way!— so I'm pretty sure I'll be just fine with a dual boot. My intent with Sailfish is to replace the laptop actually, for all those times when it's just too much and I only need a quick terminal session.

Thanks for that.

I have been running Sailfish OS as my main smartphone since launch (November 2013) on various devices (Jolla 1, Jolla c, Xperia X) and while definitely not perfect I find it totally usable in this role.

And having a real Linux distro in your pocket is really really nice & only illustrates how stripped down are regular Android phones and tablets every time I interact with one.

This is music to my ears.

> illustrates how stripped down are regular Android phones and tablets

Oh don't get me started on that... I could probably write a short novel about it. But you know that already. Part of me feels disappointed that of all the Linux-y podcasts and blogs and comments I've been exposed to over the years, it took me this long to identify Sailfish as my probable salvation.

It may be worth looking into postmarketOS, although chances are your device won't be well supported from the start.
Your reply doesn't make sense since Samsung can simple relax its SELinux if this were actually the issue (they did this in the past, btw, to implement some features in the past). Remember that SELinux is simple a set of rules that can be overridden or removed, you just need privileged access, that you know, Samsung completely does in their devices.

More likely: Linux on DeX had much less adoption than Samsung thought it would have, so after Android 10 they simple decided it wasn't worth continuing development.

Wouldn't google disallow this? i.e. if you allow access, you can't brand it "Android".

OTOH your explanation is eminently plausible. A dual desktop/phone seemed like a cool idea to me several years ago, but people would rather just use their phones. Plus, people now use websites/services more than local applications - and services like dropbox have largely solved the rest of the files-anywhere problem.

> Wouldn't google disallow this? i.e. if you allow access, you can't brand it "Android".

Maybe if you're removing restrictions for all applications (this may make Android CTS to not pass). However I was mostly thinking of Samsung only giving elevated privileges for DeX, that is completely fine too (even some Google applications have those relaxed restrictions, i.e. Google Play).

In this later case I don't see Google disallowing this, because you're not effectively reducing Android security.

> even some Google applications have those relaxed restrictions, i.e. Google Play

Google doesn't allow those apps on Google Play (clarifying because it's confusing i.e. you can't get an alternative to google play from google play).

While DeX isn't downloaded from Google Play, so that restriction doesn't directly apply; I can well imagine google cracking down on it. Perhaps also on other Play alternatives.

But just my imagination - IDK.

I had to download it manually last May because the package was not available in the standard way (Beta closed? Can't remember).

But it works well on my Tab 5e. I used it a few times to work on the move. No need for an external monitor with a tablet. I guess I won't upgrade it to androidA 10 for as long as I can.

A closed ecosystem certainly provides more value to the person that controls the ecosystem, but that's never in an end-user's best interests. Google wants to bring that "benefit" in so they can monetize it, like Apple does. This is not for or about the users, it's for corporate profits, nothing more.
Many likely Samsung saw no business value on doing it further, no different than other failed attempts.

They are well know in the Android developer community for their AOSP customisations (down to the API level and having a Samsung Android SDK).

https://developer.samsung.com/samsung-dex

Shortly after i signed up for this beta with the Note 9 I got a survey email from Samsung asking me questions about monetizing this feature.

Given the lackluster development of it (like one or two releases, that was it) I suspect they discovered there wasn't enough money in it to justify the further development.

Pretty disappointing.

I was going to get a Samsung tab s4 because of DeX. Oh well, glad I waited...
Note that Linux on dex was an experiment that never made it out of beta.

dex itself will continue to live on.

dex has no particular interest, considering Android will have its own desktop mode. It was linux that interested me
Yeah, I was looking at the Note 10 for Linux on DeX. I first saw it at a Samsung developer conference and it made me consider Samsung a progressive company. Not sure I would use it regularly, but it would have been really fun to play with.
Does this mean the Dex gadget itself is completely gone, or just 'Linux on Dex'?
Only linux on dex, dex itself will continue.
The gadget part has not been needed for at least a year.
Linux containers on Android devices have a long history of failure. I wonder if there's a technical reason why they keep going under, or if it's strictly a lack of interest from end-users who want a Linux desktop environment on their phones.
No GPU acceleration was a big issue when I tried it.
Just a bunch of geeks want such environments, and it keeps getting proven by market failures that while they are vocal about it, few put their money into the devices when the opportunity arises.

A vicious cycle since OpenMoko.

Android is really a Java like based OS, with a native SDK for games, real time audio and integrating native libraries.

Those that want CLI and interactive dev environments on the go have plenty of options written in Java.

Purism to the rescue! Https://puri.sm/products/librem-5/ ..at least it's a start. Hopefully linux (FOSS) on mobile will eventually break through, it's sucks bigtime being dependent on a device from apple/google
A decent regular Linux distro running tablet with a Wacom digitizer (precise pen with pressure and tilt support) would be really nice with all the nice graphics tools we already have (Krita, Mypaint, Blender, Inkscape, etc.).

At the moment the only alternative (not counting thd horrendously expensive Windows running mobile studios sold by Wacom) is a couple high end Andrpid tablets and the Ipad Pro & their bunch of proprietary drawing apps.

Yeah. I'm hoping the Librem 5 works out well enough for Purism, that they do the same thing for tablets. :)
Pine64 is working on the PineTab in addition to the PinePhone. https://www.pine64.org/pinetab/
Interesting! But according to the specs I don't see any mention of pen support, which is quite a shame due to all the possibilities precise pointing enables on a tablet.

Oh well might still get it in case the price is right for other use cases. :)

Too bad, it was a good idea to allow “one device for everything.”

I sometimes plug my iPad Pro into a USB-C interfaced large monitor and it is nice having lots of working space but this is not laptop or desktop replacement.

A guy I was hanging out with a hackathon this weekend was using a chromebook with crouton. An update broke his crouton intsallation and he had to find another editor and another way to spin up services, containers, etc.

If you're running a linux container on a machine with a bootloader you don't control, the manufacturer can pull your card at any time for no reason. I refuse to live that way if I have a choice, even if it means crappy hardware. :p

Note you can get (very) old ThinkPads for a pittance which will be a much better platform for running Linux. Many actually prefer the T420/X220 for its keyboard and the performance is not as bad as one would think from the eight years passed since its release. As https://www.hardocp.com/article/2017/01/13/kaby_lake_7700k_v... attests from Sandy Bridge (2011 ThinkPad) to Kaby Lake (2017 ThinkPad) IPC only grew by 20%, the big changes were in efficiency allowing the move from 35W CPUs to 15W CPUs. Also, if you are just slightly handy, you could use the T430/X230 with the old keyboard hacked onto them. If you are even more handy, you could install a converter board and a full HD screen. If you are doing this to a T430s with an i7 CPU without an nVidia GPU you even get Thunderbolt, Thunderbolt 1 for sure but still, a converter allows you to attach TB3 devices. A T430s hacked so is basically the poor man's ThinkPad 25 which is the pinnacle of laptops. (Not counting the T480-ThinkPad 25 Frankenpad which is nuts.)
I am typing this on $150 refurbished x230, I also have a t440s with a retrofitted IPS screen, and t450 touchpad.

shhhhh..... stop telling the other hackers, they will buy them all! XD

So the t450 touchpad is compatible with the t440s? Tell me it has real buttons and doesn't tilt the pad to click!
The 520/420 is also easily upgradeable - in my T520 running Fedora, I have:

- switched the i5 CPU for i7-2860QM, doupling thread count while mostly keeping per thread performance

- maxed RAM to 16 GB

- put in SATA3 SSD to the 3.5 inch position

- put in a high capacity 3.5 inch spinning hard drive to ultrabay instead of DVD drive

- put in a small m2 SSD to the SATA2 m2 slot because why not

This is still my main computer, driving two full HD monitors from its docking station.

- you mean a SATA3 SSD to the 2.5 position - a high capacity 2.5 inch spinning hard drive in the ultrabay - an mSATA SSD in the mPCIe slot it's not m.2

I had a similar setup in my T420/T420s (I moved to the T420s when the first full HD boards didn't work well for the T420 and then came the sudden thaw in the keyboard winter, the ThinkPad 25).

W520 was the best old ThinkPad - still old-school keyboard, Full HD, 32GB RAM, 2x HDD/SSD.
I love my x220 i7, 16GB RAM, 500GB Samgung EVO Pro... The thing flys..
I find T480 quite decent, compared to alternatives at least (Dell XPS, MacBook Pro)
I posted https://www.reddit.com/r/thinkpad/comments/dd2i3y/can_we_tal... a few weeks ago:

> You can get still in warranty, good spec machines below 600 USD on eBay from reputable sellers, returns accepted. Extending the warranty for 1-2 more years is 50-100 USD. So, for all intents and purposes it's new. This machine is not worse than the T490, in fact it's better in some aspects like two memory slots and two batteries. It costs like half the T490 and just as good!

Discussion mentioned Europe but eBay has a nice global shipping program so you can just buy from ebay.com but also ebay.co.uk has similar prices...

Heh, I just bought an x200 for the same reason. I was able to retrofit Bluetooth, Wifi, the Hard drive to a new SSD, flash libreboot, and put in 8 GB or RAM. Debian + XFCE is amazingly fast on it

Oddly enough, I am having an issue with the keyboard though. I unplugged it and when I replugged it in, keys stopped working. Repeating that process made a lot more keys stop working as well. I have a feeling that's just because the ribbon cable was old though, so I am replacing the whole thing.

Fuck chromebooks, I once had to make a jumper out of aluminum foil to replace the bootloader on one (not all are that bad, I know). If the aluminum jumper gets dislodged during the process, you brick the machine. I still recommend chromebooks for people who just need a web-browser and are okay with Google seeing all, but I'm never again buying one for myself without finding model-specific bootloader replacement instructions and making sure that they don't require a McGuyvered jumper cable.
yep, I also put coreboot on my acer c710, becuase crouton pissed me off. I don't think mine had to rely on the jumper not falling out though -- yikes.
I have an HP x2 Chromebook. The chromeos-imposed limitations are infuriating: no on-screen keyboard access for Linux apps, no side-loaded Android apps without a wipe+dev mode, etc. However, the form factor (tablet, magnetically attached keyboard, excellent battery life, stylus, etc.) make this an acceptable trade-off for me.
Check out the Galaxy Tab S6 - it has a very nice magnetically attached keyboard acting as a decent cover.

And while this is one of the devices affected by the Linux on DeX depreciation, it still has regular DeX (basically a desktop shell for Android apps) and quite a few community maintained open source Linux chroots (such as Termux or UserLand) provide decent development environments.

Though there are some worrying developments recently kinda mirroring your worries due to Googles draconian security policy changes possibly making projects like this harder: https://github.com/termux/termux-app/issues/1072

Chromebooks now support a Linux installation officially in the form of Crostini. It runs securely in a VM and work is done to make your linux apps and sharing as first party options in Chrome OS. Crouton was never an officially released and supported product by Chrome OS. Crostini is.
Some flagship Chromebooks do, not all of them.

So if one is paying flagship prices, then why not just buy a regular laptop from a Linux vendor?

First of all it's not just flagship devices, here you go - https://chromium.googlesource.com/chromiumos/docs/+/master/c...

Also all Chromebooks produced 2019 and onwards will support Crostini. Flagship or not flagship. https://www.extremetech.com/computing/291185-all-chromebooks...

Chromebooks' update model, speed and security are way ahead of any Linux vendor. Security is the pride of this product. And the hardware quality is great too. What you buy is your prerogative but the ability to run both Android apps and also a Linux install makes Chromebooks a good value.

That just sounds like Google marketing.

First of all, speed is hardly a feature when compared with laptops on the same price range.

Specially when taking into consideration the VMs being executed, namely browser instances, gVisor and the Crostini hypervisor.

Then just like on Android devices, Chromebooks have a limited duration of updates, namely 6 years since device market release.

Hardware quality is debatable when I need to pay MacBook class prices for getting such quality.

You can get a Crostini supported device for around 400 Dollars. These are not MacBook class prices.

Chromebook's security story is far ahead. You can do your own research and you'll find ample links proving the same.

Yes I can, but that is hardly the quality and speed you are advocating versus what regular Linux laptops offer on that price range.

My Windows and Linux laptops are kept up to date since ever, with hardware encryption turned on.

Disk encryption protects you from somebody who steals your switched-off laptop.

This discussion is about the permissions that applications get. Desktop Linuxes don't have such an permission system in place - "just run as root" with ultimate trust in the application is quite common. Sandboxing isn't a thing either.

Sandboxing is surely a thing, you just have to configure it.
And that is where things fail. Expect all users to setup sandboxing on their own ? Don't make a mistake ? And "disk encryption" is not a catch all solution to security. Otherwise every OS would be secure.
Just like Chromebooks are a market failure outside the US school system, because a large target of the world population requires more than a browser manager OS on their laptops.

Amount of Chromebooks on sale across European electronic consumer stores, less than 1%.

The 1% is left for when they occasionally pop up under "deal of the day", when the shop decides to test waters and is more than happy when it finally goes away after a couple of weeks on display.

Nice, don't reply to the point on security and shift goal posts. So you admit that "disk encryption" doesn't work ? Year of the Linux Desktop wohoooo. Also did you see Windows announcement about a cloud based OS :) sounds familiar ? But sure hate a Google product. It's the fad these days.
I did answer, but you weren't paying attention.

GNU/Linux security is better than ChromeOS because the updates are guaranteed for longer than six years, if one buys a laptop from someone like System76, or plenty of small Linux shops, it can be properly configured with encryption, LinuxSE, Flatpak/Snap/whatever.

Windows is a proper OS and its cloud offerings are not new.

Have a look at all the ancient Linux routers everywhere. They have all kinds of nasty security issues up to RCE. Linux and open source doesn't solve anything by itself. It must be brought to the customer -- without interaction.

Security must be the default. Automatic updates, sane default configuration. And a user interface that supports security.

There are “wall into a store” devices at far less than MacBook/XPS/X1 prices that have good performance, stellar battery life, good displays, and run the web’s default browser alongside Android apps and almost all Linux apps (direct USB access and audio is tricky, but the Android development kit is directly supported).

It’s true that after some number of years, you switch the hardware to a different OS, including a 3rd party supported ChromeOS system or a variety of Linux distributions.

I’m not saying it’s for everyone, but I will say that it’s at least in the same class of consideration as “you could buy an old Thinkpad, and replace at least the hard drive, keyboard, display, and battery to get something similarly usable”.

Be nice if phones had a standard BIOS and allowed a competitive selection of operatings systems. Worked well for PC's in the end and Linux being one of many alternatives testaments that.
> Be nice if phones had a standard BIOS and allowed a competitive selection of operatings systems. Worked well for PC's in the end and Linux being one of many alternatives testaments that.

It worked out well for the PC platform. Not so much for IBM, though.

That made me go look for a long term stock chart. It's really kind of interesting:

https://www.macrotrends.net/stocks/charts/IBM/ibm/stock-pric...

...it would seem IBM is still in a (very volatile) huge uptrend that started in the early 90s.

Now that I think of it, you could say that if the PC platform worked out well for Linux then Linux ended up working out well for IBM.

Hence the failed PS2 attempt to retake the PC market.
There's a spec from ARM for that: https://github.com/ARM-software/ebbr

It's meant for embedded devices, but there's no reason it wouldn't fit on phones. Now, with u-boot going in roughly the same direction, and with incoming phones focusing on liberty, it might actually be possible.

Honestly, it makes me wonder if that whole program was really just part of their negotiation for the (recently announced) partnership with Microsoft to integrate Android and Windows. I can imagine them playing hard ball and telling MS that if they don't team up then their alternative will be to build out an entirely new OS based on this. Which honestly would have been quite an interesting play.
It would be cool with a (hardware) switch that you can use to go back and forth via Android and Linux? Or boot Linux and run Android ontop?
I actually had something similar setup on my previous phone - triplebooted SailfishOS and two LineageOS installs.

Only issue is I never got things like the camera working in my port of SailfishOS, and some Android apps I used wouldn't work when the phone was rooted, which is why I had one rooted Android install and one unrooted. Also, in order to switch you had to reboot into recovery and flash a zip changing which partition to boot from.

Worked relatively well though.

There was a fork of one of the bootloaders (littlekernel?) allowing multiboot way back when. There's also at least one EFI bootloader which would in theory allow an easy/nice boot menu - reflashing to switch sounds extremely painful.
Might be because of No more exec from data folder on targetAPI >= Android Q https://github.com/termux/termux-app/issues/1072
Not really, Samsung is well known for having their own customisations to AOSP.

Your link is just the latest example how Android is not really Linux.

Project Treble drivers, NDK constraints, white listed syscalls are all examples how userspace just gets to see a selective POSIX like OS.

I've always imagined for a while that eventually our phones will become our day to day "Grunt" for dumb workstations. I was hoping Linux on DeX would be the start of this. Samsung DeX by itself is still pretty cool, If I am just doing admin work / SSH it actually works pretty nicely with MS Office and <favouriteSSHProgram> on a full HD monitor with Bluetooth keyboard and mouse.

I will probably just use this in future for when I am travelling and have to do the occasional document / email etc

This is very unfortunate, even through the writing was on the wall already for a while [1]

I used LoD often. It was just perfect for on-the-go javascript hacking. In fact at least 200+ commits to the Kea project [2] were written with Linux on Dex.

The only issue I had was that with larger projects [3] when running in the Mate desktop environment, I quickly ran out of inodes... and there was no way to increment them. I had to turn off many things in vscode (file watcher) and my projects (recompile on change) to have an usable system.

Time to look for alternatives. In the worst case I can just connect to a VNC server somewhere (LoD also used VNC), but that requires constant internet access and has issues of its own. LoD was just perfect for quick code writing in airplanes, etc.

[1] https://www.sammobile.com/interviews/dex-product-manager-new...

[2] https://kea.js.org/

[3] https://github.com/mariusandra/insights