[$] Securely suspending LUKS-encrypted disks

When a laptop is asleep, its memory is not unreadable. The righttooling can attach to the computer's memory bus and read out its contents, andcold-boot attacks can theoretically read values from memory for a short timeafter the computer loses power. Thatis really an unavoidable fact about the hardware, but some users would stilllike to ensure that, even if this happens, their long-term encryption keys, such asthe key for full-disk encryption, remain unreadable. In June2026, IngoBlechschmidtdiscovered that Linux kernel versions after 6.9 (released inMay2024)were not erasing disk-encryption keys when a laptop was put to sleep, evenwhen configured to do so. He quickly identified a potential fix, which has beenmerged, but it was not a comprehensive solution.