https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=219399
--- Comment #213 from Nils Beyer <[email protected]> --- (In reply to Nils Beyer from comment #212) more statements: -------------------------------------------------------------------------------- I'm new to this myself (I work on the GPU SW side) but AFAICS there are at least three different CPU families (1 from AMD) over the last decade which require special treatment, basically making sure that no code gets executed near the end of canonical user address space. The top of user process address space is the dividing line between the least privileged code and the touch-it-and-die non-canonical address space. Over time it seems that more "safe area" is required - presumably because each new CPU generation pre-fetches further ahead than the last one. In a sense Linux (and Windows I believe) got lucky by reserving a full guard page while BSD allocated a smaller guard area. As a result BSD has had to bump the guard area (to a full page) while other OSes did not. -------------------------------------------------------------------------------- -- You are receiving this mail because: You are the assignee for the bug. _______________________________________________ [email protected] mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-bugs To unsubscribe, send any mail to "[email protected]"
