@@ -420,4 +420,6 @@ uint64_t vm_get_single_stat(struct kvm_vm *vm, const char *stat_name);
uint32_t guest_get_vcpuid(void);
+void vm_disable_nx_huge_pages(struct kvm_vm *vm);
+
#endif /* SELFTEST_KVM_UTIL_BASE_H */
@@ -2760,3 +2760,10 @@ uint64_t vm_get_single_stat(struct kvm_vm *vm, const char *stat_name)
return value;
}
+void vm_disable_nx_huge_pages(struct kvm_vm *vm)
+{
+ struct kvm_enable_cap cap = { 0 };
+
+ cap.cap = KVM_CAP_VM_DISABLE_NX_HUGE_PAGES;
+ vm_enable_cap(vm, &cap);
+}
@@ -56,12 +56,39 @@ static void check_split_count(struct kvm_vm *vm, int expected_splits)
expected_splits, actual_splits);
}
+static void help(void)
+{
+ puts("");
+ printf("usage: nx_huge_pages_test.sh [-x]\n");
+ puts("");
+ printf(" -x: Allow executable huge pages on the VM.\n");
+ puts("");
+ exit(0);
+}
+
int main(int argc, char **argv)
{
struct kvm_vm *vm;
+ bool disable_nx = false;
+ int opt;
+
+ while ((opt = getopt(argc, argv, "x")) != -1) {
+ switch (opt) {
+ case 'x':
+ disable_nx = true;
+ break;
+ case 'h':
+ default:
+ help();
+ break;
+ }
+ }
vm = vm_create(VM_MODE_DEFAULT, DEFAULT_GUEST_PHY_PAGES, O_RDWR);
+ if (disable_nx)
+ vm_disable_nx_huge_pages(vm);
+
vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS_HUGETLB,
HPAGE_PADDR_START, HPAGE_SLOT,
HPAGE_SLOT_NPAGES, 0);
@@ -81,25 +108,25 @@ int main(int argc, char **argv)
* at 2M.
*/
run_guest_code(vm, guest_code0);
- check_2m_page_count(vm, 2);
- check_split_count(vm, 2);
+ check_2m_page_count(vm, disable_nx ? 4 : 2);
+ check_split_count(vm, disable_nx ? 0 : 2);
/*
* guest_code1 is in the same huge page as data1, so it will cause
* that huge page to be remapped at 4k.
*/
run_guest_code(vm, guest_code1);
- check_2m_page_count(vm, 1);
- check_split_count(vm, 3);
+ check_2m_page_count(vm, disable_nx ? 4 : 1);
+ check_split_count(vm, disable_nx ? 0 : 3);
/* Run guest_code0 again to check that is has no effect. */
run_guest_code(vm, guest_code0);
- check_2m_page_count(vm, 1);
- check_split_count(vm, 3);
+ check_2m_page_count(vm, disable_nx ? 4 : 1);
+ check_split_count(vm, disable_nx ? 0 : 3);
/* Give recovery thread time to run */
sleep(3);
- check_2m_page_count(vm, 1);
+ check_2m_page_count(vm, disable_nx ? 4 : 1);
check_split_count(vm, 0);
/*
@@ -107,13 +134,13 @@ int main(int argc, char **argv)
* again to check that pages are mapped at 2M again.
*/
run_guest_code(vm, guest_code0);
- check_2m_page_count(vm, 2);
- check_split_count(vm, 2);
+ check_2m_page_count(vm, disable_nx ? 4 : 2);
+ check_split_count(vm, disable_nx ? 0 : 2);
/* Pages are once again split from running guest_code1. */
run_guest_code(vm, guest_code1);
- check_2m_page_count(vm, 1);
- check_split_count(vm, 3);
+ check_2m_page_count(vm, disable_nx ? 4 : 1);
+ check_split_count(vm, disable_nx ? 0 : 3);
kvm_vm_free(vm);
@@ -14,7 +14,7 @@ echo 1 > /sys/module/kvm/parameters/nx_huge_pages_recovery_ratio
echo 2 > /sys/module/kvm/parameters/nx_huge_pages_recovery_period_ms
echo 200 > /sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages
-./nx_huge_pages_test
+./nx_huge_pages_test "${@}"
RET=$?
echo $NX_HUGE_PAGES > /sys/module/kvm/parameters/nx_huge_pages
Add an argument to the NX huge pages test to test disabling the feature on a VM using the new capability. Signed-off-by: Ben Gardon <bgardon@google.com> --- .../selftests/kvm/include/kvm_util_base.h | 2 + tools/testing/selftests/kvm/lib/kvm_util.c | 7 +++ .../selftests/kvm/x86_64/nx_huge_pages_test.c | 49 ++++++++++++++----- .../kvm/x86_64/nx_huge_pages_test.sh | 2 +- 4 files changed, 48 insertions(+), 12 deletions(-)