linux/tools/testing/selftests/kvm/x86/hyperv_evmcs.c
Sean Christopherson 67730e6c53 KVM: selftests: Use canonical $(ARCH) paths for KVM selftests directories
Use the kernel's canonical $(ARCH) paths instead of the raw target triple
for KVM selftests directories.  KVM selftests are quite nearly the only
place in the entire kernel that using the target triple for directories,
tools/testing/selftests/drivers/s390x being the lone holdout.

Using the kernel's preferred nomenclature eliminates the minor, but
annoying, friction of having to translate to KVM's selftests directories,
e.g. for pattern matching, opening files, running selftests, etc.

Opportunsitically delete file comments that reference the full path of the
file, as they are obviously prone to becoming stale, and serve no known
purpose.

Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Acked-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Acked-by: Andrew Jones <ajones@ventanamicro.com>
Link: https://lore.kernel.org/r/20241128005547.4077116-16-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18 14:15:04 -08:00

307 lines
8.6 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2018, Red Hat, Inc.
*
* Tests for Enlightened VMCS, including nested guest state.
*/
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
#include <linux/bitmap.h>
#include "test_util.h"
#include "kvm_util.h"
#include "hyperv.h"
#include "vmx.h"
static int ud_count;
static void guest_ud_handler(struct ex_regs *regs)
{
ud_count++;
regs->rip += 3; /* VMLAUNCH */
}
static void guest_nmi_handler(struct ex_regs *regs)
{
}
static inline void rdmsr_from_l2(uint32_t msr)
{
/* Currently, L1 doesn't preserve GPRs during vmexits. */
__asm__ __volatile__ ("rdmsr" : : "c"(msr) :
"rax", "rbx", "rdx", "rsi", "rdi", "r8", "r9",
"r10", "r11", "r12", "r13", "r14", "r15");
}
/* Exit to L1 from L2 with RDMSR instruction */
void l2_guest_code(void)
{
u64 unused;
GUEST_SYNC(7);
GUEST_SYNC(8);
/* Forced exit to L1 upon restore */
GUEST_SYNC(9);
vmcall();
/* MSR-Bitmap tests */
rdmsr_from_l2(MSR_FS_BASE); /* intercepted */
rdmsr_from_l2(MSR_FS_BASE); /* intercepted */
rdmsr_from_l2(MSR_GS_BASE); /* not intercepted */
vmcall();
rdmsr_from_l2(MSR_GS_BASE); /* intercepted */
/* L2 TLB flush tests */
hyperv_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE | HV_HYPERCALL_FAST_BIT, 0x0,
HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES | HV_FLUSH_ALL_PROCESSORS);
rdmsr_from_l2(MSR_FS_BASE);
/*
* Note: hypercall status (RAX) is not preserved correctly by L1 after
* synthetic vmexit, use unchecked version.
*/
__hyperv_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE | HV_HYPERCALL_FAST_BIT, 0x0,
HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES | HV_FLUSH_ALL_PROCESSORS,
&unused);
/* Done, exit to L1 and never come back. */
vmcall();
}
void guest_code(struct vmx_pages *vmx_pages, struct hyperv_test_pages *hv_pages,
vm_vaddr_t hv_hcall_page_gpa)
{
#define L2_GUEST_STACK_SIZE 64
unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE];
wrmsr(HV_X64_MSR_GUEST_OS_ID, HYPERV_LINUX_OS_ID);
wrmsr(HV_X64_MSR_HYPERCALL, hv_hcall_page_gpa);
x2apic_enable();
GUEST_SYNC(1);
GUEST_SYNC(2);
enable_vp_assist(hv_pages->vp_assist_gpa, hv_pages->vp_assist);
evmcs_enable();
GUEST_ASSERT(prepare_for_vmx_operation(vmx_pages));
GUEST_SYNC(3);
GUEST_ASSERT(load_evmcs(hv_pages));
GUEST_ASSERT(vmptrstz() == hv_pages->enlightened_vmcs_gpa);
GUEST_SYNC(4);
GUEST_ASSERT(vmptrstz() == hv_pages->enlightened_vmcs_gpa);
prepare_vmcs(vmx_pages, l2_guest_code,
&l2_guest_stack[L2_GUEST_STACK_SIZE]);
GUEST_SYNC(5);
GUEST_ASSERT(vmptrstz() == hv_pages->enlightened_vmcs_gpa);
current_evmcs->revision_id = -1u;
GUEST_ASSERT(vmlaunch());
current_evmcs->revision_id = EVMCS_VERSION;
GUEST_SYNC(6);
vmwrite(PIN_BASED_VM_EXEC_CONTROL, vmreadz(PIN_BASED_VM_EXEC_CONTROL) |
PIN_BASED_NMI_EXITING);
/* L2 TLB flush setup */
current_evmcs->partition_assist_page = hv_pages->partition_assist_gpa;
current_evmcs->hv_enlightenments_control.nested_flush_hypercall = 1;
current_evmcs->hv_vm_id = 1;
current_evmcs->hv_vp_id = 1;
current_vp_assist->nested_control.features.directhypercall = 1;
*(u32 *)(hv_pages->partition_assist) = 0;
GUEST_ASSERT(!vmlaunch());
GUEST_ASSERT_EQ(vmreadz(VM_EXIT_REASON), EXIT_REASON_EXCEPTION_NMI);
GUEST_ASSERT_EQ((vmreadz(VM_EXIT_INTR_INFO) & 0xff), NMI_VECTOR);
GUEST_ASSERT(vmptrstz() == hv_pages->enlightened_vmcs_gpa);
/*
* NMI forces L2->L1 exit, resuming L2 and hope that EVMCS is
* up-to-date (RIP points where it should and not at the beginning
* of l2_guest_code(). GUEST_SYNC(9) checkes that.
*/
GUEST_ASSERT(!vmresume());
GUEST_SYNC(10);
GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL);
current_evmcs->guest_rip += 3; /* vmcall */
/* Intercept RDMSR 0xc0000100 */
vmwrite(CPU_BASED_VM_EXEC_CONTROL, vmreadz(CPU_BASED_VM_EXEC_CONTROL) |
CPU_BASED_USE_MSR_BITMAPS);
__set_bit(MSR_FS_BASE & 0x1fff, vmx_pages->msr + 0x400);
GUEST_ASSERT(!vmresume());
GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_MSR_READ);
current_evmcs->guest_rip += 2; /* rdmsr */
/* Enable enlightened MSR bitmap */
current_evmcs->hv_enlightenments_control.msr_bitmap = 1;
GUEST_ASSERT(!vmresume());
GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_MSR_READ);
current_evmcs->guest_rip += 2; /* rdmsr */
/* Intercept RDMSR 0xc0000101 without telling KVM about it */
__set_bit(MSR_GS_BASE & 0x1fff, vmx_pages->msr + 0x400);
/* Make sure HV_VMX_ENLIGHTENED_CLEAN_FIELD_MSR_BITMAP is set */
current_evmcs->hv_clean_fields |= HV_VMX_ENLIGHTENED_CLEAN_FIELD_MSR_BITMAP;
GUEST_ASSERT(!vmresume());
/* Make sure we don't see EXIT_REASON_MSR_READ here so eMSR bitmap works */
GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL);
current_evmcs->guest_rip += 3; /* vmcall */
/* Now tell KVM we've changed MSR-Bitmap */
current_evmcs->hv_clean_fields &= ~HV_VMX_ENLIGHTENED_CLEAN_FIELD_MSR_BITMAP;
GUEST_ASSERT(!vmresume());
GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_MSR_READ);
current_evmcs->guest_rip += 2; /* rdmsr */
/*
* L2 TLB flush test. First VMCALL should be handled directly by L0,
* no VMCALL exit expected.
*/
GUEST_ASSERT(!vmresume());
GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_MSR_READ);
current_evmcs->guest_rip += 2; /* rdmsr */
/* Enable synthetic vmexit */
*(u32 *)(hv_pages->partition_assist) = 1;
GUEST_ASSERT(!vmresume());
GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == HV_VMX_SYNTHETIC_EXIT_REASON_TRAP_AFTER_FLUSH);
GUEST_ASSERT(!vmresume());
GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL);
GUEST_SYNC(11);
/* Try enlightened vmptrld with an incorrect GPA */
evmcs_vmptrld(0xdeadbeef, hv_pages->enlightened_vmcs);
GUEST_ASSERT(vmlaunch());
GUEST_ASSERT(ud_count == 1);
GUEST_DONE();
}
void inject_nmi(struct kvm_vcpu *vcpu)
{
struct kvm_vcpu_events events;
vcpu_events_get(vcpu, &events);
events.nmi.pending = 1;
events.flags |= KVM_VCPUEVENT_VALID_NMI_PENDING;
vcpu_events_set(vcpu, &events);
}
static struct kvm_vcpu *save_restore_vm(struct kvm_vm *vm,
struct kvm_vcpu *vcpu)
{
struct kvm_regs regs1, regs2;
struct kvm_x86_state *state;
state = vcpu_save_state(vcpu);
memset(&regs1, 0, sizeof(regs1));
vcpu_regs_get(vcpu, &regs1);
kvm_vm_release(vm);
/* Restore state in a new VM. */
vcpu = vm_recreate_with_one_vcpu(vm);
vcpu_set_hv_cpuid(vcpu);
vcpu_enable_evmcs(vcpu);
vcpu_load_state(vcpu, state);
kvm_x86_state_cleanup(state);
memset(&regs2, 0, sizeof(regs2));
vcpu_regs_get(vcpu, &regs2);
TEST_ASSERT(!memcmp(&regs1, &regs2, sizeof(regs2)),
"Unexpected register values after vcpu_load_state; rdi: %lx rsi: %lx",
(ulong) regs2.rdi, (ulong) regs2.rsi);
return vcpu;
}
int main(int argc, char *argv[])
{
vm_vaddr_t vmx_pages_gva = 0, hv_pages_gva = 0;
vm_vaddr_t hcall_page;
struct kvm_vcpu *vcpu;
struct kvm_vm *vm;
struct ucall uc;
int stage;
TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_VMX));
TEST_REQUIRE(kvm_has_cap(KVM_CAP_NESTED_STATE));
TEST_REQUIRE(kvm_has_cap(KVM_CAP_HYPERV_ENLIGHTENED_VMCS));
TEST_REQUIRE(kvm_hv_cpu_has(HV_X64_NESTED_DIRECT_FLUSH));
vm = vm_create_with_one_vcpu(&vcpu, guest_code);
hcall_page = vm_vaddr_alloc_pages(vm, 1);
memset(addr_gva2hva(vm, hcall_page), 0x0, getpagesize());
vcpu_set_hv_cpuid(vcpu);
vcpu_enable_evmcs(vcpu);
vcpu_alloc_vmx(vm, &vmx_pages_gva);
vcpu_alloc_hyperv_test_pages(vm, &hv_pages_gva);
vcpu_args_set(vcpu, 3, vmx_pages_gva, hv_pages_gva, addr_gva2gpa(vm, hcall_page));
vcpu_set_msr(vcpu, HV_X64_MSR_VP_INDEX, vcpu->id);
vm_install_exception_handler(vm, UD_VECTOR, guest_ud_handler);
vm_install_exception_handler(vm, NMI_VECTOR, guest_nmi_handler);
pr_info("Running L1 which uses EVMCS to run L2\n");
for (stage = 1;; stage++) {
vcpu_run(vcpu);
TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_IO);
switch (get_ucall(vcpu, &uc)) {
case UCALL_ABORT:
REPORT_GUEST_ASSERT(uc);
/* NOT REACHED */
case UCALL_SYNC:
break;
case UCALL_DONE:
goto done;
default:
TEST_FAIL("Unknown ucall %lu", uc.cmd);
}
/* UCALL_SYNC is handled here. */
TEST_ASSERT(!strcmp((const char *)uc.args[0], "hello") &&
uc.args[1] == stage, "Stage %d: Unexpected register values vmexit, got %lx",
stage, (ulong)uc.args[1]);
vcpu = save_restore_vm(vm, vcpu);
/* Force immediate L2->L1 exit before resuming */
if (stage == 8) {
pr_info("Injecting NMI into L1 before L2 had a chance to run after restore\n");
inject_nmi(vcpu);
}
/*
* Do KVM_GET_NESTED_STATE/KVM_SET_NESTED_STATE for a freshly
* restored VM (before the first KVM_RUN) to check that
* KVM_STATE_NESTED_EVMCS is not lost.
*/
if (stage == 9) {
pr_info("Trying extra KVM_GET_NESTED_STATE/KVM_SET_NESTED_STATE cycle\n");
vcpu = save_restore_vm(vm, vcpu);
}
}
done:
kvm_vm_free(vm);
}