diff options
Diffstat (limited to 'tools')
-rw-r--r-- | tools/testing/selftests/kvm/x86_64/fix_hypercall_test.c | 43 |
1 files changed, 16 insertions, 27 deletions
diff --git a/tools/testing/selftests/kvm/x86_64/fix_hypercall_test.c b/tools/testing/selftests/kvm/x86_64/fix_hypercall_test.c index 6864eb0d5d14..cebc84b26352 100644 --- a/tools/testing/selftests/kvm/x86_64/fix_hypercall_test.c +++ b/tools/testing/selftests/kvm/x86_64/fix_hypercall_test.c @@ -25,27 +25,16 @@ static void guest_ud_handler(struct ex_regs *regs) GUEST_DONE(); } -extern uint8_t svm_hypercall_insn[HYPERCALL_INSN_SIZE]; -static uint64_t svm_do_sched_yield(uint8_t apic_id) -{ - uint64_t ret; - - asm volatile("svm_hypercall_insn:\n\t" - "vmmcall\n\t" - : "=a"(ret) - : "a"((uint64_t)KVM_HC_SCHED_YIELD), "b"((uint64_t)apic_id) - : "memory"); +static const uint8_t vmx_vmcall[HYPERCALL_INSN_SIZE] = { 0x0f, 0x01, 0xc1 }; +static const uint8_t svm_vmmcall[HYPERCALL_INSN_SIZE] = { 0x0f, 0x01, 0xd9 }; - return ret; -} - -extern uint8_t vmx_hypercall_insn[HYPERCALL_INSN_SIZE]; -static uint64_t vmx_do_sched_yield(uint8_t apic_id) +extern uint8_t hypercall_insn[HYPERCALL_INSN_SIZE]; +static uint64_t do_sched_yield(uint8_t apic_id) { uint64_t ret; - asm volatile("vmx_hypercall_insn:\n\t" - "vmcall\n\t" + asm volatile("hypercall_insn:\n\t" + ".byte 0xcc,0xcc,0xcc\n\t" : "=a"(ret) : "a"((uint64_t)KVM_HC_SCHED_YIELD), "b"((uint64_t)apic_id) : "memory"); @@ -55,25 +44,25 @@ static uint64_t vmx_do_sched_yield(uint8_t apic_id) static void guest_main(void) { - uint8_t *native_hypercall_insn, *hypercall_insn; - uint8_t apic_id; - - apic_id = GET_APIC_ID_FIELD(xapic_read_reg(APIC_ID)); + const uint8_t *native_hypercall_insn; + const uint8_t *other_hypercall_insn; if (is_intel_cpu()) { - native_hypercall_insn = vmx_hypercall_insn; - hypercall_insn = svm_hypercall_insn; - svm_do_sched_yield(apic_id); + native_hypercall_insn = vmx_vmcall; + other_hypercall_insn = svm_vmmcall; } else if (is_amd_cpu()) { - native_hypercall_insn = svm_hypercall_insn; - hypercall_insn = vmx_hypercall_insn; - vmx_do_sched_yield(apic_id); + native_hypercall_insn = svm_vmmcall; + other_hypercall_insn = vmx_vmcall; } else { GUEST_ASSERT(0); /* unreachable */ return; } + memcpy(hypercall_insn, other_hypercall_insn, HYPERCALL_INSN_SIZE); + + do_sched_yield(GET_APIC_ID_FIELD(xapic_read_reg(APIC_ID))); + /* * The hypercall didn't #UD (guest_ud_handler() signals "done" if a #UD * occurs). Verify that a #UD is NOT expected and that KVM patched in |