On Wed, 25 Apr 2018, Mikulas Patocka wrote: > You need to enable it on boot. Enabling it when the kernel starts to > execute userspace code is already too late (because you would miss > kvmalloc calls in the kernel boot path). > Is your motivation that since kvmalloc() never falls back to vmalloc() on boot because fragmentation is not be an issue at boot that we should catch bugs where it would matter if it had fallen back? If we are worrying about falling back to vmalloc before even initscripts have run I think we have bigger problems.