diff options
| -rw-r--r-- | tools/testing/selftests/kvm/.gitignore | 1 | ||||
| -rw-r--r-- | tools/testing/selftests/kvm/Makefile | 1 | ||||
| -rw-r--r-- | tools/testing/selftests/kvm/include/x86_64/processor.h | 4 | ||||
| -rw-r--r-- | tools/testing/selftests/kvm/lib/x86_64/processor.c | 92 | ||||
| -rw-r--r-- | tools/testing/selftests/kvm/x86_64/emulator_error_test.c | 219 |
5 files changed, 317 insertions, 0 deletions
diff --git a/tools/testing/selftests/kvm/.gitignore b/tools/testing/selftests/kvm/.gitignore index 14c550d64d3c..d5bc9bf3b528 100644 --- a/tools/testing/selftests/kvm/.gitignore +++ b/tools/testing/selftests/kvm/.gitignore @@ -8,6 +8,7 @@ /x86_64/cr4_cpuid_sync_test /x86_64/debug_regs /x86_64/evmcs_test +/x86_64/emulator_error_test /x86_64/get_cpuid_test /x86_64/get_msr_index_features /x86_64/kvm_pv_test diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile index 279051fb901c..bc65c57ae40d 100644 --- a/tools/testing/selftests/kvm/Makefile +++ b/tools/testing/selftests/kvm/Makefile @@ -41,6 +41,7 @@ LIBKVM_s390x = lib/s390x/processor.c lib/s390x/ucall.c lib/s390x/diag318_test_ha TEST_GEN_PROGS_x86_64 = x86_64/cr4_cpuid_sync_test TEST_GEN_PROGS_x86_64 += x86_64/get_msr_index_features TEST_GEN_PROGS_x86_64 += x86_64/evmcs_test +TEST_GEN_PROGS_x86_64 += x86_64/emulator_error_test TEST_GEN_PROGS_x86_64 += x86_64/get_cpuid_test TEST_GEN_PROGS_x86_64 += x86_64/hyperv_clock TEST_GEN_PROGS_x86_64 += x86_64/hyperv_cpuid diff --git a/tools/testing/selftests/kvm/include/x86_64/processor.h b/tools/testing/selftests/kvm/include/x86_64/processor.h index 914b0d16929c..6d27a5435971 100644 --- a/tools/testing/selftests/kvm/include/x86_64/processor.h +++ b/tools/testing/selftests/kvm/include/x86_64/processor.h @@ -399,6 +399,10 @@ void vcpu_init_descriptor_tables(struct kvm_vm *vm, uint32_t vcpuid); void vm_handle_exception(struct kvm_vm *vm, int vector, void (*handler)(struct ex_regs *)); +uint64_t vm_get_page_table_entry(struct kvm_vm *vm, int vcpuid, uint64_t vaddr); +void vm_set_page_table_entry(struct kvm_vm *vm, int vcpuid, uint64_t vaddr, + uint64_t pte); + /* * set_cpuid() - overwrites a matching cpuid entry with the provided value. * matches based on ent->function && ent->index. returns true diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c index 5e0e3a131dad..3114b18454d5 100644 --- a/tools/testing/selftests/kvm/lib/x86_64/processor.c +++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c @@ -282,6 +282,98 @@ void virt_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr) __virt_pg_map(vm, vaddr, paddr, X86_PAGE_SIZE_4K); } +static struct pageTableEntry *_vm_get_page_table_entry(struct kvm_vm *vm, int vcpuid, + uint64_t vaddr) +{ + uint16_t index[4]; + struct pageUpperEntry *pml4e, *pdpe, *pde; + struct pageTableEntry *pte; + struct kvm_cpuid_entry2 *entry; + struct kvm_sregs sregs; + int max_phy_addr; + /* Set the bottom 52 bits. */ + uint64_t rsvd_mask = 0x000fffffffffffff; + + entry = kvm_get_supported_cpuid_index(0x80000008, 0); + max_phy_addr = entry->eax & 0x000000ff; + /* Clear the bottom bits of the reserved mask. */ + rsvd_mask = (rsvd_mask >> max_phy_addr) << max_phy_addr; + + /* + * SDM vol 3, fig 4-11 "Formats of CR3 and Paging-Structure Entries + * with 4-Level Paging and 5-Level Paging". + * If IA32_EFER.NXE = 0 and the P flag of a paging-structure entry is 1, + * the XD flag (bit 63) is reserved. + */ + vcpu_sregs_get(vm, vcpuid, &sregs); + if ((sregs.efer & EFER_NX) == 0) { + rsvd_mask |= (1ull << 63); + } + + TEST_ASSERT(vm->mode == VM_MODE_PXXV48_4K, "Attempt to use " + "unknown or unsupported guest mode, mode: 0x%x", vm->mode); + TEST_ASSERT(sparsebit_is_set(vm->vpages_valid, + (vaddr >> vm->page_shift)), + "Invalid virtual address, vaddr: 0x%lx", + vaddr); + /* + * Based on the mode check above there are 48 bits in the vaddr, so + * shift 16 to sign extend the last bit (bit-47), + */ + TEST_ASSERT(vaddr == (((int64_t)vaddr << 16) >> 16), + "Canonical check failed. The virtual address is invalid."); + + index[0] = (vaddr >> 12) & 0x1ffu; + index[1] = (vaddr >> 21) & 0x1ffu; + index[2] = (vaddr >> 30) & 0x1ffu; + index[3] = (vaddr >> 39) & 0x1ffu; + + pml4e = addr_gpa2hva(vm, vm->pgd); + TEST_ASSERT(pml4e[index[3]].present, + "Expected pml4e to be present for gva: 0x%08lx", vaddr); + TEST_ASSERT((*(uint64_t*)(&pml4e[index[3]]) & + (rsvd_mask | (1ull << 7))) == 0, + "Unexpected reserved bits set."); + + pdpe = addr_gpa2hva(vm, pml4e[index[3]].pfn * vm->page_size); + TEST_ASSERT(pdpe[index[2]].present, + "Expected pdpe to be present for gva: 0x%08lx", vaddr); + TEST_ASSERT(pdpe[index[2]].page_size == 0, + "Expected pdpe to map a pde not a 1-GByte page."); + TEST_ASSERT((*(uint64_t*)(&pdpe[index[2]]) & rsvd_mask) == 0, + "Unexpected reserved bits set."); + + pde = addr_gpa2hva(vm, pdpe[index[2]].pfn * vm->page_size); + TEST_ASSERT(pde[index[1]].present, + "Expected pde to be present for gva: 0x%08lx", vaddr); + TEST_ASSERT(pde[index[1]].page_size == 0, + "Expected pde to map a pte not a 2-MByte page."); + TEST_ASSERT((*(uint64_t*)(&pde[index[1]]) & rsvd_mask) == 0, + "Unexpected reserved bits set."); + + pte = addr_gpa2hva(vm, pde[index[1]].pfn * vm->page_size); + TEST_ASSERT(pte[index[0]].present, + "Expected pte to be present for gva: 0x%08lx", vaddr); + + return &pte[index[0]]; +} + +uint64_t vm_get_page_table_entry(struct kvm_vm *vm, int vcpuid, uint64_t vaddr) +{ + struct pageTableEntry *pte = _vm_get_page_table_entry(vm, vcpuid, vaddr); + + return *(uint64_t *)pte; +} + +void vm_set_page_table_entry(struct kvm_vm *vm, int vcpuid, uint64_t vaddr, + uint64_t pte) +{ + struct pageTableEntry *new_pte = _vm_get_page_table_entry(vm, vcpuid, + vaddr); + + *(uint64_t *)new_pte = pte; +} + void virt_dump(FILE *stream, struct kvm_vm *vm, uint8_t indent) { struct pageUpperEntry *pml4e, *pml4e_start; diff --git a/tools/testing/selftests/kvm/x86_64/emulator_error_test.c b/tools/testing/selftests/kvm/x86_64/emulator_error_test.c new file mode 100644 index 000000000000..f070ff0224fa --- /dev/null +++ b/tools/testing/selftests/kvm/x86_64/emulator_error_test.c @@ -0,0 +1,219 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2020, Google LLC. + * + * Tests for KVM_CAP_EXIT_ON_EMULATION_FAILURE capability. + */ + +#define _GNU_SOURCE /* for program_invocation_short_name */ + +#include "test_util.h" +#include "kvm_util.h" +#include "vmx.h" + +#define VCPU_ID 1 +#define PAGE_SIZE 4096 +#define MAXPHYADDR 36 + +#define MEM_REGION_GVA 0x0000123456789000 +#define MEM_REGION_GPA 0x0000000700000000 +#define MEM_REGION_SLOT 10 +#define MEM_REGION_SIZE PAGE_SIZE + +static void guest_code(void) +{ + __asm__ __volatile__("flds (%[addr])" + :: [addr]"r"(MEM_REGION_GVA)); + + GUEST_DONE(); +} + +static void run_guest(struct kvm_vm *vm) +{ + int rc; + + rc = _vcpu_run(vm, VCPU_ID); + TEST_ASSERT(rc == 0, "vcpu_run failed: %d\n", rc); +} + +/* + * Accessors to get R/M, REG, and Mod bits described in the SDM vol 2, + * figure 2-2 "Table Interpretation of ModR/M Byte (C8H)". + */ +#define GET_RM(insn_byte) (insn_byte & 0x7) +#define GET_REG(insn_byte) ((insn_byte & 0x38) >> 3) +#define GET_MOD(insn_byte) ((insn_byte & 0xc) >> 6) + +/* Ensure we are dealing with a simple 2-byte flds instruction. */ +static bool is_flds(uint8_t *insn_bytes, uint8_t insn_size) +{ + return insn_size >= 2 && + insn_bytes[0] == 0xd9 && + GET_REG(insn_bytes[1]) == 0x0 && + GET_MOD(insn_bytes[1]) == 0x0 && + /* Ensure there is no SIB byte. */ + GET_RM(insn_bytes[1]) != 0x4 && + /* Ensure there is no displacement byte. */ + GET_RM(insn_bytes[1]) != 0x5; +} + +static void process_exit_on_emulation_error(struct kvm_vm *vm) +{ + struct kvm_run *run = vcpu_state(vm, VCPU_ID); + struct kvm_regs regs; + uint8_t *insn_bytes; + uint8_t insn_size; + uint64_t flags; + + TEST_ASSERT(run->exit_reason == KVM_EXIT_INTERNAL_ERROR, + "Unexpected exit reason: %u (%s)", + run->exit_reason, + exit_reason_str(run->exit_reason)); + + TEST_ASSERT(run->emulation_failure.suberror == KVM_INTERNAL_ERROR_EMULATION, + "Unexpected suberror: %u", + run->emulation_failure.suberror); + + if (run->emulation_failure.ndata >= 1) { + flags = run->emulation_failure.flags; + if ((flags & KVM_INTERNAL_ERROR_EMULATION_FLAG_INSTRUCTION_BYTES) && + run->emulation_failure.ndata >= 3) { + insn_size = run->emulation_failure.insn_size; + insn_bytes = run->emulation_failure.insn_bytes; + + TEST_ASSERT(insn_size <= 15 && insn_size > 0, + "Unexpected instruction size: %u", + insn_size); + + TEST_ASSERT(is_flds(insn_bytes, insn_size), + "Unexpected instruction. Expected 'flds' (0xd9 /0)"); + + /* + * If is_flds() succeeded then the instruction bytes + * contained an flds instruction that is 2-bytes in + * length (ie: no prefix, no SIB, no displacement). + */ + vcpu_regs_get(vm, VCPU_ID, ®s); + regs.rip += 2; + vcpu_regs_set(vm, VCPU_ID, ®s); + } + } +} + +static void do_guest_assert(struct kvm_vm *vm, struct ucall *uc) +{ + TEST_FAIL("%s at %s:%ld", (const char *)uc->args[0], __FILE__, + uc->args[1]); +} + +static void check_for_guest_assert(struct kvm_vm *vm) +{ + struct kvm_run *run = vcpu_state(vm, VCPU_ID); + struct ucall uc; + + if (run->exit_reason == KVM_EXIT_IO && + get_ucall(vm, VCPU_ID, &uc) == UCALL_ABORT) { + do_guest_assert(vm, &uc); + } +} + +static void process_ucall_done(struct kvm_vm *vm) +{ + struct kvm_run *run = vcpu_state(vm, VCPU_ID); + struct ucall uc; + + check_for_guest_assert(vm); + + TEST_ASSERT(run->exit_reason == KVM_EXIT_IO, + "Unexpected exit reason: %u (%s)", + run->exit_reason, + exit_reason_str(run->exit_reason)); + + TEST_ASSERT(get_ucall(vm, VCPU_ID, &uc) == UCALL_DONE, + "Unexpected ucall command: %lu, expected UCALL_DONE (%d)", + uc.cmd, UCALL_DONE); +} + +static uint64_t process_ucall(struct kvm_vm *vm) +{ + struct kvm_run *run = vcpu_state(vm, VCPU_ID); + struct ucall uc; + + TEST_ASSERT(run->exit_reason == KVM_EXIT_IO, + "Unexpected exit reason: %u (%s)", + run->exit_reason, + exit_reason_str(run->exit_reason)); + + switch (get_ucall(vm, VCPU_ID, &uc)) { + case UCALL_SYNC: + break; + case UCALL_ABORT: + do_guest_assert(vm, &uc); + break; + case UCALL_DONE: + process_ucall_done(vm); + break; + default: + TEST_ASSERT(false, "Unexpected ucall"); + } + + return uc.cmd; +} + +int main(int argc, char *argv[]) +{ + struct kvm_enable_cap emul_failure_cap = { + .cap = KVM_CAP_EXIT_ON_EMULATION_FAILURE, + .args[0] = 1, + }; + struct kvm_cpuid_entry2 *entry; + struct kvm_cpuid2 *cpuid; + struct kvm_vm *vm; + uint64_t gpa, pte; + uint64_t *hva; + int rc; + + /* Tell stdout not to buffer its content */ + setbuf(stdout, NULL); + + vm = vm_create_default(VCPU_ID, 0, guest_code); + + if (!kvm_check_cap(KVM_CAP_SMALLER_MAXPHYADDR)) { + printf("module parameter 'allow_smaller_maxphyaddr' is not set. Skipping test.\n"); + return 0; + } + + cpuid = kvm_get_supported_cpuid(); + + entry = kvm_get_supported_cpuid_index(0x80000008, 0); + entry->eax = (entry->eax & 0xffffff00) | MAXPHYADDR; + set_cpuid(cpuid, entry); + + vcpu_set_cpuid(vm, VCPU_ID, cpuid); + + rc = kvm_check_cap(KVM_CAP_EXIT_ON_EMULATION_FAILURE); + TEST_ASSERT(rc, "KVM_CAP_EXIT_ON_EMULATION_FAILURE is unavailable"); + vm_enable_cap(vm, &emul_failure_cap); + + vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, + MEM_REGION_GPA, MEM_REGION_SLOT, + MEM_REGION_SIZE / PAGE_SIZE, 0); + gpa = vm_phy_pages_alloc(vm, MEM_REGION_SIZE / PAGE_SIZE, + MEM_REGION_GPA, MEM_REGION_SLOT); + TEST_ASSERT(gpa == MEM_REGION_GPA, "Failed vm_phy_pages_alloc\n"); + virt_map(vm, MEM_REGION_GVA, MEM_REGION_GPA, 1); + hva = addr_gpa2hva(vm, MEM_REGION_GPA); + memset(hva, 0, PAGE_SIZE); + pte = vm_get_page_table_entry(vm, VCPU_ID, MEM_REGION_GVA); + vm_set_page_table_entry(vm, VCPU_ID, MEM_REGION_GVA, pte | (1ull << 36)); + + run_guest(vm); + process_exit_on_emulation_error(vm); + run_guest(vm); + + TEST_ASSERT(process_ucall(vm) == UCALL_DONE, "Expected UCALL_DONE"); + + kvm_vm_free(vm); + + return 0; +} |