On Tue, Feb 11, 2014 at 12:43:35PM -0600, Christoph Lameter wrote: > On Tue, 11 Feb 2014, Pekka Enberg wrote: > > > So again, there's nothing in (A) that the memory allocator is > > concerned about. kmalloc() makes no guarantees whatsoever about the > > visibility of "r1" across CPUs. If you're saying that there's an > > implicit barrier between kmalloc() and kfree(), that's an unintended > > side-effect, not a design decision AFAICT. > > I am not sure that this side effect necessarily happens. The SLUB fastpath > does not disable interrupts and only uses a cmpxchg without lock > semantics. That tells me what I need to know. Users should definitely not try a "drive-by kfree()" of something that was concurrently allocated. ;-) Thanx, Paul -- 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=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>