On Tue, May 29, 2018 at 09:40:09AM -0700, Dave Hansen wrote: > Split-lock-detection is a new hardware feature that generates > alignment-check (#AC) faults to help detect when badly-aligned atomic > instructions might impact whole-system performance. These patches are > primarily targeted at application-level issues, but we can also detect > the same issues in the kernel.
Which is nice, Thomas and me spend quite a while searching for a perf event that could tell us about unaligned LOCK insns a few months back and could not find anything useful. > There is a significant interaction > between this feature and firmware because firmware may or may not be > prepared for this feature to be enabled. And allowing firmware to muddle through, instead of drawing a hard line in the sand means we'll be stuck with crap firmware for at least another decade :/ Just say no.
