On Fri, Mar 11, 2016 at 12:47 PM, Andrey Ryabinin <ryabinin.a.a@xxxxxxxxx> wrote: > 2016-03-09 14:05 GMT+03:00 Alexander Potapenko <glider@xxxxxxxxxx>: > >> +struct kasan_track { >> + u64 cpu : 6; /* for NR_CPUS = 64 */ > > What about NR_CPUS > 64 ? After a discussion with Dmitry we've decided to drop |cpu| and |when| at all, as they do not actually help debugging. This way we'll make kasan_track only 8 bytes (4 bytes for PID, 4 bytes for stack handle). Then the meta structures will be smaller and have nice alignment: struct kasan_track { u32 pid; depot_stack_handle_t stack; }; struct kasan_alloc_meta { struct kasan_track track; u32 state : 2; /* enum kasan_state */ u32 alloc_size : 30; u32 reserved; /* we can use it to store an additional stack handle, e.g. for debugging RCU */ }; struct kasan_free_meta { /* This field is used while the object is in the quarantine. * Otherwise it might be used for the allocator freelist. */ void **quarantine_link; struct kasan_track track; }; >> + u64 pid : 16; /* 65536 processes */ >> + u64 when : 42; /* ~140 years */ >> +}; >> + -- Alexander Potapenko Software Engineer Google Germany GmbH Erika-Mann-Straße, 33 80636 München Geschäftsführer: Matthew Scott Sucherman, Paul Terence Manicle Registergericht und -nummer: Hamburg, HRB 86891 Sitz der Gesellschaft: Hamburg -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href