Add coverate for running a guest with no memslots, and for deleting memslots while the guest is running. Enhance the test to use, and expect, a unique value for MMIO reads, e.g. to verify each stage of the test. Signed-off-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx> --- .../kvm/x86_64/set_memory_region_test.c | 122 ++++++++++++++++-- 1 file changed, 108 insertions(+), 14 deletions(-) diff --git a/tools/testing/selftests/kvm/x86_64/set_memory_region_test.c b/tools/testing/selftests/kvm/x86_64/set_memory_region_test.c index c6691cff4e19..44aed8ac932b 100644 --- a/tools/testing/selftests/kvm/x86_64/set_memory_region_test.c +++ b/tools/testing/selftests/kvm/x86_64/set_memory_region_test.c @@ -26,42 +26,109 @@ #define MEM_REGION_SIZE 0x200000 #define MEM_REGION_SLOT 10 -static void guest_code(void) +static const uint64_t MMIO_VAL = 0xbeefull; + +extern const uint64_t final_rip_start; +extern const uint64_t final_rip_end; + +static inline uint64_t guest_spin_on_val(uint64_t spin_val) { uint64_t val; do { val = READ_ONCE(*((uint64_t *)MEM_REGION_GPA)); - } while (!val); + } while (val == spin_val); + return val; +} - if (val != 1) - ucall(UCALL_ABORT, 1, val); +static void guest_code(void) +{ + uint64_t val; - GUEST_DONE(); + /* + * Spin until the memory region is moved to a misaligned address. This + * may or may not trigger MMIO, as the window where the memslot is + * invalid is quite small. + */ + val = guest_spin_on_val(0); + GUEST_ASSERT(val == 1 || val == MMIO_VAL); + + /* Spin until the memory region is realigned. */ + GUEST_ASSERT(guest_spin_on_val(MMIO_VAL) == 1); + + /* Spin until the memory region is deleted. */ + GUEST_ASSERT(guest_spin_on_val(1) == MMIO_VAL); + + /* Spin until the memory region is recreated. */ + GUEST_ASSERT(guest_spin_on_val(MMIO_VAL) == 0); + + /* Spin until the memory region is deleted. */ + GUEST_ASSERT(guest_spin_on_val(0) == MMIO_VAL); + + asm("1:\n\t" + ".pushsection .rodata\n\t" + ".global final_rip_start\n\t" + "final_rip_start: .quad 1b\n\t" + ".popsection"); + + /* Spin indefinitely (until the code memslot is deleted). */ + guest_spin_on_val(MMIO_VAL); + + asm("1:\n\t" + ".pushsection .rodata\n\t" + ".global final_rip_end\n\t" + "final_rip_end: .quad 1b\n\t" + ".popsection"); + + GUEST_ASSERT(0); } static void *vcpu_worker(void *data) { struct kvm_vm *vm = data; + struct kvm_regs regs; struct kvm_run *run; struct ucall uc; - uint64_t cmd; /* * Loop until the guest is done. Re-enter the guest on all MMIO exits, - * which will occur if the guest attempts to access a memslot while it - * is being moved. + * which will occur if the guest attempts to access a memslot after it + * has been deleted or while it is being moved . */ run = vcpu_state(vm, VCPU_ID); - do { + + memcpy(run->mmio.data, &MMIO_VAL, 8); + while (1) { vcpu_run(vm, VCPU_ID); - } while (run->exit_reason == KVM_EXIT_MMIO); + if (run->exit_reason != KVM_EXIT_MMIO) + break; - TEST_ASSERT(run->exit_reason == KVM_EXIT_IO, + TEST_ASSERT(!run->mmio.is_write, "Unexpected exit mmio write"); + TEST_ASSERT(run->mmio.len == 8, + "Unexpected exit mmio size = %u", run->mmio.len); + + TEST_ASSERT(run->mmio.phys_addr == MEM_REGION_GPA, + "Unexpected exit mmio address = 0x%llx", + run->mmio.phys_addr); + } + + if (run->exit_reason == KVM_EXIT_IO) { + (void)get_ucall(vm, VCPU_ID, &uc); + TEST_FAIL("%s at %s:%ld", + (const char *)uc.args[0], __FILE__, uc.args[1]); + } + + TEST_ASSERT(run->exit_reason == KVM_EXIT_SHUTDOWN || + run->exit_reason == KVM_INTERNAL_ERROR_EMULATION, "Unexpected exit reason = %d", run->exit_reason); - cmd = get_ucall(vm, VCPU_ID, &uc); - TEST_ASSERT(cmd == UCALL_DONE, "Unexpected val in guest = %lu", uc.args[0]); + vcpu_regs_get(vm, VCPU_ID, ®s); + + TEST_ASSERT(regs.rip >= final_rip_start && + regs.rip < final_rip_end, + "Bad rip, expected 0x%lx - 0x%lx, got 0x%llx\n", + final_rip_start, final_rip_end, regs.rip); + return NULL; } @@ -72,6 +139,13 @@ static void test_move_memory_region(void) uint64_t *hva; uint64_t gpa; + vm = vm_create(VM_MODE_DEFAULT, 0, O_RDWR); + vm_vcpu_add(vm, VCPU_ID); + /* Fails with ENOSPC because the MMU can't create pages (no slots). */ + TEST_ASSERT(_vcpu_run(vm, VCPU_ID) == -1 && errno == ENOSPC, + "Unexpected error code = %d", errno); + kvm_vm_free(vm); + vm = vm_create_default(VCPU_ID, 0, guest_code); vcpu_set_cpuid(vm, VCPU_ID, kvm_get_supported_cpuid()); @@ -105,7 +179,6 @@ static void test_move_memory_region(void) */ vm_mem_region_move(vm, MEM_REGION_SLOT, MEM_REGION_GPA - 4096); WRITE_ONCE(*hva, 2); - usleep(100000); /* @@ -116,6 +189,27 @@ static void test_move_memory_region(void) /* Restore the original base, the guest should see "1". */ vm_mem_region_move(vm, MEM_REGION_SLOT, MEM_REGION_GPA); + usleep(100000); + + /* Delete the memory region, the guest should not die. */ + vm_mem_region_delete(vm, MEM_REGION_SLOT); + usleep(100000); + + /* Recreate the memory region. The guest should see "0". */ + vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS_THP, + MEM_REGION_GPA, MEM_REGION_SLOT, + MEM_REGION_SIZE / getpagesize(), 0); + usleep(100000); + + /* Delete the region again so that there's only one memslot left. */ + vm_mem_region_delete(vm, MEM_REGION_SLOT); + usleep(100000); + + /* + * Delete the primary memslot. This should cause an emulation error or + * shutdown due to the page tables getting nuked. + */ + vm_mem_region_delete(vm, VM_PRIMARY_MEM_SLOT); pthread_join(vcpu_thread, NULL); -- 2.24.1