[PATCH v1 08/13] KVM: selftests: Fix prefault_mem logic

James Houghton
2024-12-04T19:14:23Z

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@google.com>
---
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