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Saint Meltdown, Who Melted the Wall Between User and Kernel
Patron of over-optimistic processors and sysadmins who watched performance drop after the patch.
Life
Revealed to the world on 3 January 2018 together with his brother Spectre, with a logo and a website as befits a modern saint. He taught that a processor, to go fast, reads ahead even what it shouldn't, and that the secret stays imprinted in the cache. To exorcise him, operating systems had to separate kernel memory from program memory, in a rite called KPTI.
Prayer
O Saint Meltdown, who read kernel memory without permission, teach our processors that speculation is no sin only as long as it leaves no trace. Amen.
How to celebrate
Celebrated by updating microcode and kernel, and looking resignedly at the next day's benchmarks.
Slow and steady wins the race; speculate, and you leave a trace.