News: 0182830202

  ARM Give a man a fire and he's warm for a day, but set fire to him and he's warm for the rest of his life (Terry Pratchett, Jingo)

Linux Drops ISDN Subsystem and Other Old Network Drivers

(Saturday April 25, 2026 @05:26PM (EditorDavid) from the something-old-something-new dept.)


"Old code like amateur radio and NFC have long been a burden to core networking developers," reads the pull request.

And so Thursday Linus Torvald merged the pull request "to rid the Linux kernel of the old Integrated Services Digital Network (ISDN) subsystem," [1]reports Phoronix , "and various other old network drivers largely for PCMCIA era network adapters."

> This was the code suggested for removal given the recent influx of AI/LLM-generated bug reports against this dated code that likely has no active upstream users remaining... [W]ith the large language models and increased code fuzzing finding potential issues with these drivers for obsolete hardware, it's easier to just get rid of these drivers if no one is actively using the hardware from decades ago... [2]This merge lightens the kernel by 138,161 lines of code with ISDN gone and numerous old network adapters and also getting rid of legacy ATM device drivers as well as the amateur ham radio support. The main networking drivers removed affect the 3com 3c509 / 3c515 / 3c574 / 3c589, AMD Lance, AMD NMCLAN, SMSC SMC9194 / SMC91C92, Fujitsu FMVJ18X, and 8390 AX88190 / Ultra / WD80X3.

>

> Linux 7.1 also has [3]removed the long-obsolete bus mouse support as well as [4]beginning to phase out Intel 486 CPU support and [5]removing support for Russia's Baikal CPUs .



[1] https://www.phoronix.com/news/Linux-7.1-Removes-Old-Net

[2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=64edfa65062dc4509ba75978116b2f6d392346f5

[3] https://www.phoronix.com/news/Linux-7.1-Input

[4] https://www.phoronix.com/news/Linux-7.1-Phasing-Out-i486

[5] https://www.phoronix.com/news/Linux-Dropping-Baikal-CPUs



The Windows 11ing of Linux (Score:1)

by xack ( 5304745 )

Now all these obsolete devices have to be landfilled instead of being used in retro computing environments. Everything is being trashed due to AI. I've also heard of many indie websites shutting down due to only getting views from scrapers.

Re:The Windows 11ing of Linux (Score:4, Insightful)

by JoshuaZ ( 1134087 )

Aside from these devices all being very rare, how does this force any of them to be landfilled? It isn't like you won't be able to download or use an older version of Linux.

Re: (Score:2)

by HiThere ( 15173 )

Would it work to run a older distro virtually? I'm not sure, though I suspect it wouldn't.

Re:The Windows 11ing of Linux (Score:4, Funny)

by organgtool ( 966989 )

When Linux ends support for a device, the Linux Gnome sneaks into the building and destroys the unsupported hardware. Everybody knows this.

Re: The Windows 11ing of Linux (Score:4, Informative)

by FudRucker ( 866063 )

You can always download an older distro or build an older version of the Linux kernel and build it, it's just the new versions won't be having it, I think some repos still have Slackware-3.3 from way back in1997 if you want it

Re: (Score:3)

by serviscope_minor ( 664417 )

I mean it's only 7.1, not 7.0 it's being removed from. You could use ubuntu 2.04, at which point EOL would be some time around 2030, at which point it would become a little more difficult to run a 40 year old network card in a fully patched OS.

I mean that's ignoring the difficulties of trying to run an ISA card these days.

Re: (Score:2, Informative)

by Anonymous Coward

> I mean it's only 7.1, not 7.0 it's being removed from. You could use ubuntu 2.04, at which point EOL would be some time around 2030, at which point it would become a little more difficult to run a 40 year old network card in a fully patched OS.

> I mean that's ignoring the difficulties of trying to run an ISA card these days.

Fortunately ISA bus support is a hard requirement for pATA IDE disks.

Also fortunate for GP, they won't notice any difference between their driver supported ISDN card that isn't plugged in to anything, and their soon to be unsupported ISDN card still not plugged in to anything.

You haven't been able to get ISDN or POTS service in the USA for almost a decade now.

Most other nations don't either.

Even the few nations in the EU that might still have ISDN service and an ISP to call with it, that would be moot as ol

Re: (Score:1)

by Hurricane Floyd ( 891704 )

It is zero actually.

Re: (Score:2)

by eneville ( 745111 )

> instead of being used in retro computing environments

Would you want 7.x running on retro hardware? An environment like is is probably going to be setup in a 'classic' way and unlikely to be running bleeding edge.

Re: (Score:1)

by Hurricane Floyd ( 891704 )

You have no idea what you are even talking about.

Re: (Score:2)

by apparently ( 756613 )

> Now all these obsolete devices have to be landfilled instead of being used in retro computing environments. Everything is being trashed due to AI. I've also heard of many indie websites shutting down due to only getting views from scrapers.

You don't know wtf you're talking about. Why would these devices be upgrading to this kernel? And in the situation that they NEEDED to upgrade to this kernel, why wouldn't they just...compile a version of this kernel with the device drivers added back in?

Again, you don't know wtf you're talking about.

no one is using a 3c509 yea no don't believe that (Score:2)

by ghinckley68 ( 590599 )

this and the ne2000 were littlery the gold standard to get a isa based machine on a network.

Re: (Score:2)

by organgtool ( 966989 )

A prize in litterery.

Re:no one is using a 3c509 yea no don't believe th (Score:5, Funny)

by demon driver ( 1046738 )

Right. Not even 35 years old, the 3C509. I remember it like it were yesterday how we wrapped coax cable around that three-storey house with rented flats to get us four people connected. Probably need to go back to OS/2 if Linux drops support!

Re: (Score:3)

by svx ( 764251 )

...and when your buddy killed you in Quake, you could pull out your terminator and take the whole network down

Re: (Score:1)

by Anonymous Coward

Yeah, in 1995.

There's likely next to zero people who have a legitimate use case for running an NE2000 or 3c509 on a machine that is actually capable of running a modern Linux kernel.

Re: (Score:3)

by karmawarrior ( 311177 )

A real NE2000 or 3c509? Sure, probably not.

But an emulated one is extremely likely. Their ubiquitousness made them primary targets for cloning in both hardware and software, especially with virtualization. I have to say I'm pretty surprised they'd discontinue support for them on that basis alone.

And if the argument is "LOL old code! Code rot! genAI bug submissions overload!" then remember we're also talking about extremely simple devices by today's standards, with very little of the layered abstracted archi

Re:no one is using a 3c509 yea no don't believe th (Score:4, Insightful)

by serviscope_minor ( 664417 )

A lot of these devices just need one grizzled old hacker to maintain them (as in the plural, one programmer, multiple legacy devices.)

And are you?

Re: no one is using a 3c509 yea no don't believe t (Score:2)

by Tomahawk ( 1343 )

"A lot of these devices just need one grizzled old hacker to maintain them", and the number of people maintaining them is..... zero!

Re: (Score:2)

by Kernel Kurtz ( 182424 )

> A lot of these devices just need one grizzled old hacker to maintain them (as in the plural, one programmer, multiple legacy devices.)

A grizzled old hacker who actually needs these devices themselves. Otherwise your grizzled hacking skills are still better used elsewhere.

Re: (Score:2)

by thegarbz ( 1787294 )

> this and the ne2000 were littlery the gold standard to get a isa based machine on a network.

You missed the context. No one is using this on a hyper modern OS running the latest and greatest kernel. SystemD doesn't even have a systemd-isad module.

Re: (Score:1)

by warp_kez ( 711090 )

And the 21140 based PCI for 10/100 whose drivers were twitchy depending on the OEM.

But I remember those techs! (Score:5, Funny)

by JoshuaZ ( 1134087 )

Bus mouses were not that common, but we're a thing when I was growing up. But the phasing out of the 486 support is really what I have to object to. It was cutting edge when I was young, so if it is now so rare and obsolete that support isn't justified then I must be old and that can't be right. I don't care for Linux's refusal to indulge my denial of the passage of time.

used this like 30 years ago (Score:1)

by Matthieu Araman ( 823 )

I remember using a isdn card on linux about 30 years ago. It was very useful at the time

. But not sure there is any network left that could use it nowadays....and if no users can test fixes, then it is better to remove these drivers

Re: (Score:2)

by _merlin ( 160982 )

I miss ISDN. Only 20 years ago, all Japanese payphones still had ISDN ports. I wrote software to handle downloading updates over ISDN while cooperating with point-of-sale systems that also needed to use the ISDN lines. All these moments will be lost in time like tears in rain.

Re: (Score:2)

by karmawarrior ( 311177 )

I must admit to being a little surprised but also suspecting my reason for surprise is wrong. ISDN was always essentially the core digital phone system exposed as much as possible to the subscriber. So it's always been relevant as long as we had a digital (uhm, direct digital might be a better term) phone system.

But I suspect almost all phone companies have switched to Voice-over-IP now. It's not even practical to get POTS phone service in this region, I know, we tried to get it for my elderly in-laws a few

Re: (Score:2)

by PPH ( 736903 )

What about all the people around here (Seattle area) who lose POTS service every time a meth addict cuts down the phone cables for the copper?

Re: (Score:2)

by sarren1901 ( 5415506 )

As was just mentioned, it's all digital now so that's not really happening unless the cable company is hanging those same wires off the poles. Then you'll have Internet and your landline will go down. Of course, I haven't had a landline in 20+ years. The only people I know that have one are legacy cable subscription bundles and even those folks have individual cellphones as well. Maybe someone in the mid to late 80s (do those count as boomers or silent generation?).

Re: (Score:2)

by PPH ( 736903 )

> As was just mentioned, it's all digital now

And some people think it's all daises and everyone gets a pony. They need to come out here and visit the real world. We still get news stories every few months showing copper-pair cables cut down a few hundred feet at a time by our local addicts.

Nobody uses HAM-based packet radio? (Score:5, Interesting)

by jd ( 1658 )

That surprises me. Obviously, if it's true it's true, but with satellite Internet availability decided by politics, and Internet traffic regularly monitored, I'd have thought some people in remote communities would prefer alternatives. I've been known to be wrong on occasion, and if this happens to be such an occasion, then ok. It just seems... odd that people desperate to be seen as independent and off the regular grid would deliberately not use technology that would permit them to communicate long-distance on a grid they themselves had control over.

Re: Nobody uses HAM-based packet radio? (Score:2)

by FudRucker ( 866063 )

The most common digital I seen on hf ham is psk31 and sstv, psk31 is text only and with software on a PC it is about like IRC chatrooms you can find them on 14.070 mhz on the 20 meter band, and sstv is usually on 14.230 mhz and is usually just sending an image or photo over the air and it can be decoded and displayed with software too

Re: Nobody uses HAM-based packet radio? (Score:2)

by FudRucker ( 866063 )

It is easier than that now, audio out on the radio to audio in on the computer, fire up your favorite decoding software and it listens & decodes the digital on the fly with fldigi which is pretty good except fldigi doesn't do sstv, a qt based app qsstv will do sstv

Re: (Score:2)

by tannhaus ( 152710 )

Well, packet radio is still used. You have things like APRS which broadcasts location for location tracking, you have things like winlink so you can send emails over amateur radio, and you even have packet radio BBSs. But, the last one is the only one that would really use that kernel code and it's very uncommon. There's no reason it shouldn't be all userspace utilities.

Re: (Score:2)

by jd ( 1658 )

Open Source is not, and never has been, about the money.

Re: (Score:3)

by Burdell ( 228580 )

Apparently nobody is using the Linux kernel's drivers for it, these days it's done purely in user-space with no need for kernel drivers.

Re: (Score:2)

by AmiMoJo ( 196126 )

I guess it's the same for NFC. It's all USB devices, even the internal NFC readers.

Such a missed opportunity. So much more could be done with NFC.

No more ISDN? (Score:1)

by Valgrus Thunderaxe ( 8769977 )

There goes 1/4 of Seattle from the internet.

Re: (Score:1)

by Narcocide ( 102829 )

+1 Underrated; Isn't most of downtown Seattle still stuck on ISDN due to a combination of legal and logistical restrictions, or is that not the case anymore?

An argument for user space driver interfaces? (Score:2)

by karmawarrior ( 311177 )

I feel like this wouldn't be a big issue (or at least one we're debating) if there were stable APIs for things like user space network card drivers. Mind you, I don't know how well that'd work with ISA devices.

Old Hardware (Score:1)

by Hurricane Floyd ( 891704 )

Quit whining about this making old hardware useless. Older releases of distros will remain available indefinitely. Old hardware can not run modern Linux to start with. And modern systems can not use this vintage hardware. There was absolutely no reason for the modern Linux kernel to drag this code with it until the end of time.

I remember ISDN (Score:4, Funny)

by MpVpRb ( 1423381 )

When I worked in IT in the 90s, I struggled with SPIDs and provisioning

I even wrote a set of lyrics about it, set to the music of YMCA by the Village People

Phone man, oh my modem's too slow

I need answers, and I'm ready to go

What's the distance to my local CO

Am I close enough to get it

Phone man, oh I need it today

I can't wait for the fiber coming my way

It's one hundred and twenty eight K

And it's good enough

So get me

ISDN

You know I'm talkin' bout

ISDN

It's the best you can get

But the word on the street

Says it's already obsolete

ISDN....

Poorly summarised (Score:3)

by ukoda ( 537183 )

> Old code like amateur radio and NFC

Is poorly stated as both are actively used. Yes amateur radio usage is well below it former peak usage as the motivation for using it has changed, but it is still popular with people who like to explore technology with the rise of SDRs driving interest. Likewise NFC is now has record use in daily life.

Instead of making it sound like support for amateur radio and NFC was being removed they should have said support for some long obsolete hardware was being removed.

ISDN: It Still Does Nothing (Score:2)

by ewhac ( 5844 )

(a/k/a Innovation Subscribers Don't Need)

It still amazes me that, as late as the 1990's, and well after 56kbit modems were prolific, ISDN was being offered up by the ILECs as "broadband," at metered rates that made Ma Bell's long distance charges look like spare change.

Happily, it wasn't too long before ISDN was put out of everyone's misery when DSL showed up. And now, finally, after fifty years of pissing about, fiber is finally being pulled to the premises.

If you really need ongoing ISDN support, y

Please spare 3c905 (Score:2)

by WaffleMonster ( 969671 )

I hope corrosive levels of delete happy mentality do not invade Linux Kernel development. It would suck to see Linux go in the direction of Wikipedia or LibreSSL.

Amateur Radio? (Score:2)

by Ol Olsoc ( 1175323 )

I'm curious what ham radio apps are affected that aren't available in much better form that run on modern equipment. And really, if you really wanted to run ancient applications on an ancient computer, there are ancient Linux distros. There's no law that says we have to be on the latest versions of Linux and its kernel.

The notes blatted skyward as they rose over the Canada geese, feathered
rumps mooning the day, webbed appendages frantically pedaling unseen
bicycles in their search for sustenance, driven by cruel Nature's maxim,
'Ya wanna eat, ya gotta work,' and at last I knew Pittsburgh.
-- Winning sentence, 1987 Bulwer-Lytton bad fiction contest.