A recent Linux kernel commit (6.11) addresses key aspects of SD card compatibility and support, most namely adding support for Ultra High-Speed II SD cards (UHS-II) and Ultra Capacity SD cards (dubbed SDUC) [h/t Phoronix]. UHS-II SD cards support speeds up to 312 MB/s, while SDUC cards have a theoretical maximum capacity of 128 TB and can support yet faster UHS-III and SD Express speeds.
Regarding SDUC cards and capacity, we saw 4 TB SDUC cards back in April, and since then, an 8 TB SDUC card has also been announced. That is expected to increase over time, hence the 128 TB ceiling.
