The previous logic didn't handle the case where memory was partitioned AND we were using a single userfaultfd. It would only prefault the first vCPU's memory and not the rest. Signed-off-by: James Houghton <jthoughton@xxxxxxxxxx> --- tools/testing/selftests/kvm/demand_paging_test.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/kvm/demand_paging_test.c b/tools/testing/selftests/kvm/demand_paging_test.c index 0202b78f8680..315f5c9037b4 100644 --- a/tools/testing/selftests/kvm/demand_paging_test.c +++ b/tools/testing/selftests/kvm/demand_paging_test.c @@ -172,11 +172,13 @@ static void run_test(enum vm_guest_mode mode, void *arg) memset(guest_data_prototype, 0xAB, demand_paging_size); if (p->uffd_mode == UFFDIO_REGISTER_MODE_MINOR) { - num_uffds = p->single_uffd ? 1 : nr_vcpus; - for (i = 0; i < num_uffds; i++) { + for (i = 0; i < nr_vcpus; i++) { vcpu_args = &memstress_args.vcpu_args[i]; prefault_mem(addr_gpa2alias(vm, vcpu_args->gpa), vcpu_args->pages * memstress_args.guest_page_size); + if (!p->partition_vcpu_memory_access) + /* We prefaulted everything */ + break; } } -- 2.47.0.338.g60cca15819-goog