linux

undreds of devices, and then a couple of months later, thousands) launch, and had pretty much every conceivable issue thrown at us, from faulty USB hubs, broken modems (which would also kill the USB hub if they pulled too much power), and I'm sure I've forgotten a bunch of other issues. Plus, since the problem took a week to manifest, we couldn't really iterate on fixes quickly - after deploying a "potential fix", we'd have to wait a whole week to actually see if it worked. I can vividly remember the joy I had when I managed to get the issue to consistently happen only in the span of 2 hours instead of a week. I had no idea _why_, but at least I could now get serviceable feedback loops. Eventually, after trying to mess with every variable we could, and isolating this specific issue from the other ones, we somehow figured out that the issue was indeed a bug in the kernel, or at least in one of its drivers: https://github.com/raspberrypi/linux/issues/5088 . We had many serial ports and a pattern of opening and closing them which triggered the issue. Upgrading the kernel was impossible due to a specific vendor lock-in, and we had to fix live devices and ship hundreds of them in less than a month. In the end, we managed to build several layers on top of this unpatchable ever-growing USB-incapacitating bug: (i) we changed our serial port access patterns to significantly reduce the frequency of crashes; (ii) we adjusted boot parameters to make it much harder to trigger (aka "throw more memory at the memory leak"); (iii) we built a system that proactively detected the issue and triggered a USB reset in a very controlled fashion (this would sometimes kill the network of the device for a while, but we had no choice!); (iv) if, for some reason, all else failed, a watchdog would still reboot the system (but we really _really_ _reaaaally_ didn't want this to happen). In a way, even though these issues suck, it's when we are faced with them that we really grow. We need to grab our whole troubleshooting arsenal, do things that would otherwise feel "wrong" or "inelegant", and push through the issues. Just thinking back to that period, I'm engulfed by a mix of gratitude for how much I learned, and an uneasy sense of dread (what if next time I won't be able to figure it out)?

ts/8be08...>“ <https://www.jeffgeerling.com/comment/34061#comment-34061> Something broke. Without going through the obsd code it remains unknown. Unless there is reference to uart3 & uart4?

h has full hardware-accelerated desktop/server Ubuntu 22.04/24.04 LTS support. https://github.com/Joshua-Riek/ubuntu-rockchip The VPU used by video decoding has nothing to do with 3D/GPU. With `ffmpeg-rockchip` and `libv4l-rkmpp` you get 4k@60 hw decoding support in Chromium and MPV player, and 8k@60 hw decoding support in Kodi. https://github.com/nyanmisaka/ffmpeg-rockchip/wiki/Rendering Jellyfin also provides complete transcoding pipeline support on the RK3588 based SBCs. https://jellyfin.org/docs/general/administration/hardware-ac...

y nic like '/etc/systemd/network/10-eth10.link' and fill it like: [Match] MACAddress=75:1a:d3:80:85:59 [Link] Name=eth10 And then update your initramfs: update-initramfs -u And ready! :) > It is the most basic task for Linux computer... Well, it depends for whom. Also, you need adequate software and hardware. About wireless, the chipset in an RPi4 is designed for clients, not APs, and its capabilities on having multiple clients are quite limited: https://github.com/raspberrypi/linux/issues/3010 Routers like the Omnia Turris, Mikrotik, PC Engines... use specific mini PCIe cards that can be as expensive as a full Raspberry Pi 4, just for the wireless. https://www.discomp.eu/wireless-minipci-cards_c14501412.html