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1/* SPDX-License-Identifier: GPL-2.0-only */2#ifndef SELFTEST_KVM_FLDS_EMULATION_H3#define SELFTEST_KVM_FLDS_EMULATION_H4 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 to11 * support. This can be used in guest code along with a mechanism to force12 * KVM to emulate the instruction (e.g. by providing an MMIO address) to13 * exercise emulation failures.14 */15static inline void flds(uint64_t address)16{17 __asm__ __volatile__(FLDS_MEM_EAX :: "a"(address));18}19 20static 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