https://bugs.kde.org/show_bug.cgi?id=126348
--- Comment #6 from Vince Weaver <vincent.wea...@maine.edu> --- a further note, had to re-verify some of this because it's been a while since I dealt with the kernel side. The CR4 value is context switched, so when rdpmc is auto-enabled it is only done so for the process using perf_event. Also running perf_event_open() isn't enough to enable it, you also have to mmap() the fd returned by perf_event_open(). Only then will the PCE bit in CR4 be set. Linux was actually buggy with this code for a while and the PCE bit state could get out-of-sync related to mmap() status, but that was eventually fixed. -- You are receiving this mail because: You are watching all bug changes.
