On 4/8/20 8:01 PM, Wainer dos Santos Moschetta wrote:
On 4/8/20 10:31 PM, Krish Sadhukhan wrote:
On 4/8/20 3:08 PM, Wainer dos Santos Moschetta wrote:
This patch introduces the mem_slot_test test which checks
an 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@xxxxxxxxxx>
---
tools/testing/selftests/kvm/.gitignore | 1 +
tools/testing/selftests/kvm/Makefile | 3 +
tools/testing/selftests/kvm/mem_slot_test.c | 76
+++++++++++++++++++++
3 files changed, 80 insertions(+)
create mode 100644 tools/testing/selftests/kvm/mem_slot_test.c
diff --git a/tools/testing/selftests/kvm/.gitignore
b/tools/testing/selftests/kvm/.gitignore
index 16877c3daabf..127d27188427 100644
--- a/tools/testing/selftests/kvm/.gitignore
+++ b/tools/testing/selftests/kvm/.gitignore
@@ -21,4 +21,5 @@
/demand_paging_test
/dirty_log_test
/kvm_create_max_vcpus
+/mem_slot_test
/steal_time
diff --git a/tools/testing/selftests/kvm/Makefile
b/tools/testing/selftests/kvm/Makefile
index 712a2ddd2a27..338b6cdce1a0 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -32,12 +32,14 @@ TEST_GEN_PROGS_x86_64 += clear_dirty_log_test
TEST_GEN_PROGS_x86_64 += demand_paging_test
TEST_GEN_PROGS_x86_64 += dirty_log_test
TEST_GEN_PROGS_x86_64 += kvm_create_max_vcpus
+TEST_GEN_PROGS_x86_64 += mem_slot_test
TEST_GEN_PROGS_x86_64 += steal_time
TEST_GEN_PROGS_aarch64 += clear_dirty_log_test
TEST_GEN_PROGS_aarch64 += demand_paging_test
TEST_GEN_PROGS_aarch64 += dirty_log_test
TEST_GEN_PROGS_aarch64 += kvm_create_max_vcpus
+TEST_GEN_PROGS_aarch64 += mem_slot_test
TEST_GEN_PROGS_aarch64 += steal_time
TEST_GEN_PROGS_s390x = s390x/memop
@@ -46,6 +48,7 @@ TEST_GEN_PROGS_s390x += s390x/sync_regs_test
TEST_GEN_PROGS_s390x += demand_paging_test
TEST_GEN_PROGS_s390x += dirty_log_test
TEST_GEN_PROGS_s390x += kvm_create_max_vcpus
+TEST_GEN_PROGS_s390x += mem_slot_test
TEST_GEN_PROGS += $(TEST_GEN_PROGS_$(UNAME_M))
LIBKVM += $(LIBKVM_$(UNAME_M))
diff --git a/tools/testing/selftests/kvm/mem_slot_test.c
b/tools/testing/selftests/kvm/mem_slot_test.c
new file mode 100644
index 000000000000..7c1009f0bc07
--- /dev/null
+++ b/tools/testing/selftests/kvm/mem_slot_test.c
@@ -0,0 +1,76 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * mem_slot_test
+ *
+ * Copyright (C) 2020, Red Hat, Inc.
+ *
+ * Test suite for memory region operations.
+ */
+#define _GNU_SOURCE /* for program_invocation_short_name */
+#include <linux/kvm.h>
+#include <sys/mman.h>
+
+#include "test_util.h"
+#include "kvm_util.h"
+
+/*
+ * 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_slots(void)
+{
+ int ret;
+ struct kvm_vm *vm;
+ uint32_t max_mem_slots;
+ uint32_t slot;
+ uint64_t guest_addr;
+ uint64_t mem_reg_npages;
+ uint64_t mem_reg_size;
+ 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);
+
+ /*
+ * Uses 1MB sized/aligned memory region since this is the minimal
+ * required on s390x.
+ */
+ mem_reg_size = 0x100000;
+ mem_reg_npages = vm_calc_num_guest_pages(VM_MODE_DEFAULT,
mem_reg_size);
+
+ guest_addr = 0x0;
Nit: Can't this be initialized where it's defined above ?
I don't have a strong preference. Is it generally initialized on
definition on kvm (selftests or not) code?
Some places do it where the variable is defined. For example, in smm_test.c,
vm_vaddr_t vmx_pages_gva = 0;
It reduces an extra line.
+
+ /* Check it can be added memory slots up to the maximum allowed */
+ pr_info("Adding slots 0..%i, each memory region with %ldK size\n",
+ (max_mem_slots - 1), mem_reg_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_reg_size;
+ }
+
+ /* Check it cannot be added memory slots beyond the limit */
+ mem = mmap(NULL, mem_reg_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_reg_size, (uint64_t) mem});
+ TEST_ASSERT(ret == -1 && errno == EINVAL,
+ "Adding one more memory slot should fail with EINVAL");
Why not add a test here for adding memory at an existing slot ?
Good question.
I'm working on another test which should check it cannot be added
overlapping slots. I will send it in a separate patch series,
depending on the fate of this one. :)
More precisely, those are the cases I will cover on this new test:
0x100000 0x300000
0x0 0x200000 0x400000
slot0 | |---2MB--| (SUCCESS)
slot1 |---2MB--| (FAIL)
slot2 |---2MB--| (SUCCESS)
slot3 |---2MB--| (FAIL)
slot4 |---2MB--| (FAIL)
slot5 |---2MB--| (SUCCESS)
Thanks!
Wainer
OK.
Reviewed-by: Krish Sadhukhan <krish.sadhukhan@xxxxxxxxxx>
+
+ munmap(mem, mem_reg_size);
+ kvm_vm_free(vm);
+}
+
+int main(int argc, char *argv[])
+{
+ test_add_max_slots();
+ return 0;
+}
