1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 #ifndef SELFTEST_KVM_FLDS_EMULATION_H 3 #define SELFTEST_KVM_FLDS_EMULATION_H 4 5 #include "kvm_util.h" 6 7 #define FLDS_MEM_EAX ".byte 0xd9, 0x00" 8 9 /* 10 * flds is an instruction that the KVM instruction emulator is known not to 11 * support. This can be used in guest code along with a mechanism to force 12 * KVM to emulate the instruction (e.g. by providing an MMIO address) to 13 * exercise emulation failures. 14 */ 15 static inline void flds(uint64_t address) 16 { 17 __asm__ __volatile__(FLDS_MEM_EAX :: "a"(address)); 18 } 19 20 static inline void handle_flds_emulation_failure_exit(struct kvm_vcpu *vcpu) 21 { 22 struct kvm_run *run = vcpu->run; 23 struct kvm_regs regs; 24 uint8_t *insn_bytes; 25 uint64_t flags; 26 27 TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_INTERNAL_ERROR); 28 29 TEST_ASSERT(run->emulation_failure.suberror == KVM_INTERNAL_ERROR_EMULATION, 30 "Unexpected suberror: %u", 31 run->emulation_failure.suberror); 32 33 flags = run->emulation_failure.flags; 34 TEST_ASSERT(run->emulation_failure.ndata >= 3 && 35 flags & KVM_INTERNAL_ERROR_EMULATION_FLAG_INSTRUCTION_BYTES, 36 "run->emulation_failure is missing instruction bytes"); 37 38 TEST_ASSERT(run->emulation_failure.insn_size >= 2, 39 "Expected a 2-byte opcode for 'flds', got %d bytes", 40 run->emulation_failure.insn_size); 41 42 insn_bytes = run->emulation_failure.insn_bytes; 43 TEST_ASSERT(insn_bytes[0] == 0xd9 && insn_bytes[1] == 0, 44 "Expected 'flds [eax]', opcode '0xd9 0x00', got opcode 0x%02x 0x%02x", 45 insn_bytes[0], insn_bytes[1]); 46 47 vcpu_regs_get(vcpu, ®s); 48 regs.rip += 2; 49 vcpu_regs_set(vcpu, ®s); 50 } 51 52 #endif /* !SELFTEST_KVM_FLDS_EMULATION_H */ 53