29.01.2015, 22:57, "Andrew Shewmaker" <[email protected]>: > On Thu, Jan 29, 2015 at 04:06:03PM +0300, Roman Gushchin wrote: >> I noticed, that "allowed" can easily overflow by falling below 0, >> because (total_vm / 32) can be larger than "allowed". The problem >> occurs in OVERCOMMIT_NONE mode. >>
> Makes sense to me. Please fix mm/nommu.c also. Thanks! I sent a patch for nommu.c. > > If a caller passes in a big negative value for pages, > then vm_acct_memory() would decrement vm_committed_as, possibly > causing percpu_counter_read_positive(&vm_committed_as) and > __vm_enough_memory to return 0. Maybe that's okay? Callers > won't be passing in a negative pages anyway. Is there a reason > to let them, though? I think, it isn't a problem, since no one will commit negative values (I hope). R. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
