From 909e0abaac0f3331e2016d4b9b19001a390d6019 Mon Sep 17 00:00:00 2001
From: Wainer dos Santos Moschetta <wainersm@redhat.com>
Date: Fri, 10 Apr 2020 16:17:07 -0700
Subject: [PATCH] selftests: kvm: Add testcase for creating max number of
memslots
This patch introduces test_add_max_memory_regions(), which checks
that a VM can have added memory slots up to the limit defined in
KVM_CAP_NR_MEMSLOTS. Then attempt to add one more slot to
verify it fails as expected.
Signed-off-by: Wainer dos Santos Moschetta <wainersm@redhat.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20200410231707.7128-11-sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
.../selftests/kvm/set_memory_region_test.c | 65 +++++++++++++++++--
1 file changed, 61 insertions(+), 4 deletions(-)
diff --git a/tools/testing/selftests/kvm/set_memory_region_test.c b/tools/testing/selftests/kvm/set_memory_region_test.c
index ac4945fa1c89b..260e638826dcc 100644
--- a/tools/testing/selftests/kvm/set_memory_region_test.c
+++ b/tools/testing/selftests/kvm/set_memory_region_test.c
@@ -9,6 +9,7 @@
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
+#include <sys/mman.h>
#include <linux/compiler.h>
@@ -18,14 +19,18 @@
#define VCPU_ID 0
+/*
+ * s390x needs at least 1MB alignment, and the x86_64 MOVE/DELETE tests need a
+ * 2MB sized and aligned region so that the initial region corresponds to
+ * exactly one large page.
+ */
+#define MEM_REGION_SIZE 0x200000
+
#ifdef __x86_64__
/*
- * Somewhat arbitrary location and slot, intended to not overlap anything. The
- * location and size are specifically 2mb sized/aligned so that the initial
- * region corresponds to exactly one large page.
+ * Somewhat arbitrary location and slot, intended to not overlap anything.
*/
#define MEM_REGION_GPA 0xc0000000
-#define MEM_REGION_SIZE 0x200000
#define MEM_REGION_SLOT 10
static const uint64_t MMIO_VAL = 0xbeefull;
@@ -312,6 +317,54 @@ static void test_zero_memory_regions(void)
}
#endif /* __x86_64__ */
+/*
+ * Test it can be added memory slots up to KVM_CAP_NR_MEMSLOTS, then any
+ * tentative to add further slots should fail.
+ */
+static void test_add_max_memory_regions(void)
+{
+ int ret;
+ struct kvm_vm *vm;
+ uint32_t max_mem_slots;
+ uint32_t slot;
+ uint64_t guest_addr = 0x0;
+ uint64_t mem_reg_npages;
+ void *mem;
+
+ max_mem_slots = kvm_check_cap(KVM_CAP_NR_MEMSLOTS);
+ TEST_ASSERT(max_mem_slots > 0,
+ "KVM_CAP_NR_MEMSLOTS should be greater than 0");
+ pr_info("Allowed number of memory slots: %i\n", max_mem_slots);
+
+ vm = vm_create(VM_MODE_DEFAULT, 0, O_RDWR);
+
+ mem_reg_npages = vm_calc_num_guest_pages(VM_MODE_DEFAULT, MEM_REGION_SIZE);
+
+ /* Check it can be added memory slots up to the maximum allowed */
+ pr_info("Adding slots 0..%i, each memory region with %dK size\n",
+ (max_mem_slots - 1), MEM_REGION_SIZE >> 10);
+ for (slot = 0; slot < max_mem_slots; slot++) {
+ vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS,
+ guest_addr, slot, mem_reg_npages,
+ 0);
+ guest_addr += MEM_REGION_SIZE;
+ }
+
+ /* Check it cannot be added memory slots beyond the limit */
+ mem = mmap(NULL, MEM_REGION_SIZE, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ TEST_ASSERT(mem != MAP_FAILED, "Failed to mmap() host");
+
+ ret = ioctl(vm_get_fd(vm), KVM_SET_USER_MEMORY_REGION,
+ &(struct kvm_userspace_memory_region) {slot, 0, guest_addr,
+ MEM_REGION_SIZE, (uint64_t) mem});
+ TEST_ASSERT(ret == -1 && errno == EINVAL,
+ "Adding one more memory slot should fail with EINVAL");
+
+ munmap(mem, MEM_REGION_SIZE);
+ kvm_vm_free(vm);
+}
+
int main(int argc, char *argv[])
{
#ifdef __x86_64__
@@ -327,7 +380,11 @@ int main(int argc, char *argv[])
* KVM_RUN fails with ENOEXEC or EFAULT.
*/
test_zero_memory_regions();
+#endif
+
+ test_add_max_memory_regions();
+#ifdef __x86_64__
if (argc > 1)
loops = atoi(argv[1]);
else
--
2.39.5