On Mon, Nov 27, 2017 at 08:57:32PM +0100, Michal Hocko wrote: > On Mon 27-11-17 19:32:18, Michal Hocko wrote: > > On Mon 27-11-17 09:25:16, Andi Kleen wrote: > [...] > > > The reason the limit was there originally because it allows a DoS > > > attack against the kernel by filling all unswappable memory up with VMAs. > > > > We can reduce the effect by accounting vmas to memory cgroups. > > As it turned out we already do. > vm_area_cachep = KMEM_CACHE(vm_area_struct, SLAB_PANIC|SLAB_ACCOUNT); That only helps if you have memory cgroups enabled. It would be a regression to break the accounting on all the systems that don't. -Andi -- 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>