Laptop: Busted, won’t boot

My new(-ish now) laptop has mostly performed great over the just-over-a-year I’ve had it, and surprisingly I hadn’t managed to ratfuck my Linux installation in that time. Well, no time like the present, because on Monday I ran pacman -Syu tcpdump, it installed a pile of packages including a kernel update, I thought nothing of it and shut the machine down. Yesterday when I went to use it, and I was faced with a dreaded message: Please enter the recovery key for disk BLAH BLAH BLAH

Whoops.

I figured that something had failed to sign, but it took me a bit to figure out. First of all, I couldn’t get into the recovery immediately, because I was typing the key wrong. Note to future self: the hyphens in the recovery key are part of it, they’re not optional for aesthetic purposes.

But I managed to boot from a USB key after turning secureboot off, but then I was unable to decrypt and mount the disk, so I figured it was maybe because my USB key was too old (from ~2025) so I made a new one. It was at that point I figured out the hyphen thing, got into it, and no, it looks like everything worked correctly?

I started thinking about what the hell could have happened, noting that it was exactly 451 days since I installed it and maybe something expired. I checked sbctl verify and everything is signed, everything should be happy, but in the end re-enrolling a new key into luks and the TPM worked:

systemd-cryptenroll --tpm2-device=auto --tpm2-pcrs=7 /dev/sdX

I rebooted, flipped secureboot back on, and it’s straight into it without needing the key, happy days. But what caused it?

I was racking my brain trying to work it out when Avi came through today with the release notes I didn’t read:

Starting with package version 42-1, the mkinitcpio systemd hook now includes systemd-pcrosseparator.service (as intended by systemd v261).

This affects the measurements of PCR values 0-7, 9 and 12-14. If you configured the systemd hook and unlock LUKS partitions, that depend on these values, you need to re-enroll the TPM2 in use.

I checked my pacman.log and sure enough, I upgraded mkinitcpio to that exact version right before the shit hit the fan, so problem solved I guess? Operator error.

Whoops.

Horsham, VIC, Australia

Author:

fwaggle

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Horsham, VIC, Australia

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Can recycling bin: Success

It’s been not quite three years since Victoria released their “container deposit scheme” (California viewers would recognize it as functionally equivalent to the CRV, only a good bit more generous to the consumer as it’s not completely captured by private interests yet). We end up with a few cans, and were keeping them in garbage bags in the garage, which we’d then transfer into the car, and feed into the machines which read each can, make sure it’s had a deposit, and then pay you for it.

This is a pain in the arse, to the point where it had crossed my mind to simply give the cans to someone else so I did not have to deal with them. But in speaking to the person cleaning the machines, they mentioned if you have a lot, there’s another place you can take them where the machine is automated - you just empty your bags onto a rack and the machine sorts them all for you. So the next time we had a car full of cans (some months later) we went to have a look, and yes, as advertised, it’s much easier.

We did still have the issue of bags full of cans in the garage, and the potential for drips in the car… but it crossed my mind: what if I just went to Bunnings and bought a wheely bin, and put it out with the other bins, and then dragged that to the redemption place when it was full? They can’t be that expensive I reasoned, and sure enough they were actually cheaper than I thought - A$139 for a 240L bin that’s fairly reasonable quality.

So we bought one, put the cans we had in it, and went “that’s very nice”. Until last weekend when we noticed it was starting to get a bit full - not desparately so, so we waited until this weekend.

I put the trailer on the car, pulled the bin up into the trailer (far easier than I thought, 240L of un-crushed aluminum cans weighs less than you’d think - the cans cannot be crushed so that the robot can read the QR code on each can), lashed it down and closed with some ratchet straps and off we went.

The place was hopping, so I had to wait a few minutes before it was my turn at the robot, but once it was, it was as advertised: lift the bin up onto the rack, up-end it, and walk out. 240L of uncrushed cans is about A$30 worth at 10c/can.

Hose out the bin when we got home and that’s that. Honestly the worst part of the whole thing is connecting the trailer (we put it around the back of the house, which means pulling it around several obstacles to attach it to the car), but I can mitigate that by scheduling things better to try coincide it with a tip run or something.

Horsham, VIC, Australia

Author:

fwaggle

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Horsham, VIC, Australia

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MacOS: Monitor woes fixed?

A long time ago, $WORK decided to migrate away from BYOD, and I sold my beloved 2015 Macbook Pro (I literally could not afford to keep it, it was worth nearly a thousand bucks, I had no use for it, and it was about to very quickly tank in value due to MacOS support falling off for it). It was replaced with an original M1 Macbook Pro, whereupon I discovered the joys [pejorative] of DisplayLink.

I hated DisplayLink so much that I ended up getting rid of my dual monitors and switching to a single 4K screen just to avoid it. However a single 4K monitor doesn’t really lend itself well to my racoon-in-a-dumpster workflow, so earlier this year after upgrading me to a fancy M4 Pro Macbook Pro (say that three times fast), $WORK bought me two things: a Thunderbolt 5 (not DisplayLink) dock and a second monitor.

This led to much annoyance, because despite the fact that TB5 has more than enough bandwidth for two 4k60 monitors, and despite the fact it worked fine on my Asus laptop with fucking Linux installed, I simply could not get the dock to light up both screens.

It turns out this is an Apple driver limitation: they simply refuse to implement Multi-stream Transport. It’s never going to work. Every dock that does work in this configuration implements it via independent adaptors, rather than two outputs of the same virtual adaptor that my dock does (and I have to stress, this dock was not cheap, it’s a Lenovo one recommended by our IT department, I am glad I didn’t pay for it).

Apparently the solution is to just buy USB-C to HDMI adaptors, so I grudgingly went off down to Betta (because fuck Gerry Harvey) and bought one. This worked as advertised, both monitors came up, everything was fine.

Except I was still having the same trouble I’d had since I got the new dock: sporadically, the monitors would sleep for 5 to 10 seconds, most of the time they’d come back, sometimes one wouldn’t. Sometimes only one would sleep. Sometimes you’d have to unplug and replug something to get it to come back. Really fucking annoying.

Reader, I tried for a solid couple of months to fix this, to no avail. I tried lower resolutions (“oh there’s not enough bandwidth!”), I tried buying newer, fancier cables (“Oh Apple stuff is just picky about the cables you use, you simply must use decent cables”, I literally bought 8K rated cables), I tried everything.

I noted again, that my Linux laptop functioned fine - what the fuck is going on in the world right now?

Finally, after having it happen for the 8th time in two hours, I did yet another Google search. Unsure if it’s because the index rearranged itself or I just happened to Prompt It Right, but I came across an old Reddit thread about a different problem, with a solution that seemed worth having a crack at:

It worked all Wednesday, including through a meeting Wednesday night without an embarassing “going dark while my camera is still on” moment. And it’s worked all the way through to the weekend without skipping a beat.

Is it too much to hope it’s fixed?

Horsham, VIC, Australia

Author:

fwaggle

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Horsham, VIC, Australia

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Computer Case Cleanout

In a case of one-thing-leads-to-another Sabriena was cleaning around her and Duncan’s shared desk and decided to clean their computers. Not before time either, Duncan’s was positively caked with dust! We’re hoping that explains the performance issues he’s been having occasionally, but it remains to be seen whether that’s the reason.

I took the opportunity to replace the old, dumb, unmanaged netgear 5 port switch with a Unifi one that I had spare, and then we cracked them open. Blew a lot of dust-bunnies out of Duncan’s machine, wiped off the fans, cleaned the filters, and put it back together.

Sabriena’s on the other hand? Pretty spotless. Her filters were of course fairly dusty, but it’s actually quite incredible the difference between them. It must be stressed, the two machines are side by side, in a little pocket on a wooden shelf, approximately 5cm off the floor under their desk in the corner.

My guess is that her case is a Be Quiet, while his is a super-cool tacticool RGB thing from Asus TUF. I am suspecting that his, despite having what I thought was adequate filtration, focuses more on moving air around and looking pretty than dust management. Both cases should have positive air pressure through filtered fans, though hers has two 140mm fans and his has three 120mm fans, with now that I think of it, the bottom fan at the front of his machine would be closer to the carpet by about 40mm.

We’ll have to do more science in 6 months time!

Horsham, VIC, Australia

Author:

fwaggle

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Horsham, VIC, Australia

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Cable Management

I pulled the trigger on Kogan about two weeks ago for some metal cable trays, and they arrived earlier this week. So I pulled them out the box, assembled, and worked out where I wanted them. They’re okay. They were very cheap, so I can’t really complain, but they are fairly floppy. Still though, my laptop dock and several associated power supplies are all up out of the way, and I can stuff the ball of cables into them.

I have one more power strip that needs screwing up underneath the desk, but for the most part I’m not kicking wall-warts any more. It’s a lot easier to manage than velcro straps and hooks, which was the strategy when we did Sabriena and Duncan’s desk.

Update: 2026-07-22: Boy howdy did the “easier to manage” come into play way sooner than I expected. On Monday I noticed that my USB hub appears to have died, which meant I had to pull everything out and re-route some things under the desk to get all my audio devices connected. It was substantially easier to just lift down the hub and the USB KVM switch, plug things where they need to go, and tuck it all back up unto the shelf.

However after buying a new hub, I learned that apparently my hub has not died. It seems as though after a MacOS update (possibly, I cannot remember), my Mac has decided to not see any device downstream of the hub. It works fine on Windows. The replacement hub does not work either. I have no idea how to fix this, my solution ended up being I just put the webcam directly into the dock for the mac… I never use it on my desktop anyway.

Horsham, VIC, Australia

Author:

fwaggle

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Horsham, VIC, Australia

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