Last week Linus Torvalds personally cleaned up the x86 memory copy code for Linux 6.4, Phoronix reports — and this week “he’s merged more of his own code as he took issue with some of the code merged by Intel engineers as part of their Linear Address Masking enabling.”
Back during the Linux 6.2 days at the end of last year, Linus rejected the Intel LAM code at the time for various technical issues. Intel then reworked it for Linux 6.4. This time around Linus merged Intel LAM into Linux 6.4 as this new CPU feature for letting user-space store metadata within some bits of pointers without masking it out before use. Intel LAM — like Arm TBI — can be of use to virtual machines, profiling / sanitizers / tagging, and other applications. But this time around there were some less than ideal code that he personally took to sprucing