On Sun 10-12-17 18:22:05, John Hubbard wrote: > On 12/10/2017 02:31 AM, Michal Hocko wrote: > > On Tue 05-12-17 19:14:34, john.hubbard@xxxxxxxxx wrote: > >> From: John Hubbard <jhubbard@xxxxxxxxxx> > >> > >> Previously, MAP_FIXED was "discouraged", due to portability > >> issues with the fixed address. In fact, there are other, more > >> serious issues. Also, alignment requirements were a bit vague. > >> So: > >> > >> -- Expand the documentation to discuss the hazards in > >> enough detail to allow avoiding them. > >> > >> -- Mention the upcoming MAP_FIXED_SAFE flag. > >> > >> -- Enhance the alignment requirement slightly. > >> > >> Some of the wording is lifted from Matthew Wilcox's review > >> (the "Portability issues" section). The alignment requirements > >> section uses Cyril Hrubis' wording, with light editing applied. > >> > >> Suggested-by: Matthew Wilcox <willy@xxxxxxxxxxxxx> > >> Suggested-by: Cyril Hrubis <chrubis@xxxxxxx> > >> Signed-off-by: John Hubbard <jhubbard@xxxxxxxxxx> > > > > Would you mind if I take this patch and resubmit it along with my > > MAP_FIXED_SAFE (or whatever name I will end up with) next week? > > > > Acked-by: Michal Hocko <mhocko@xxxxxxxx> > > Sure, that works for me. A tiny complication: I see that Michael > Kerrisk has already applied the much smaller v2 of this patch (the > one that "no longer discourages" the option, but that's all), as: > > ffa518803e14 mmap.2: MAP_FIXED is no longer discouraged > > so this one here will need to be adjusted slightly to merge > gracefully. Let me know if you want me to respin, or if you > want to handle the merge. Yes, please respin. -- Michal Hocko SUSE Labs
