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kvm: selftests: actually use all of lib/vmx.c
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The allocation of the VMXON and VMCS is currently done twice, in
lib/vmx.c and in vmx_tsc_adjust_test.c.  Reorganize the code to
provide a cleaner and easier to use API to the tests.  lib/vmx.c
now does the complete setup of the VMX data structures, but does not
create the VM or set CPUID.  This has to be done by the caller.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Paolo Bonzini committed Aug 6, 2018
1 parent 2305339 commit 87ccb7d
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Showing 3 changed files with 72 additions and 89 deletions.
21 changes: 17 additions & 4 deletions tools/testing/selftests/kvm/include/vmx.h
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Original file line number Diff line number Diff line change
Expand Up @@ -486,9 +486,22 @@ static inline uint32_t vmcs_revision(void)
return rdmsr(MSR_IA32_VMX_BASIC);
}

void prepare_for_vmx_operation(void);
void prepare_vmcs(void *guest_rip, void *guest_rsp);
struct kvm_vm *vm_create_default_vmx(uint32_t vcpuid,
vmx_guest_code_t guest_code);
struct vmx_pages {
void *vmxon_hva;
uint64_t vmxon_gpa;
void *vmxon;

void *vmcs_hva;
uint64_t vmcs_gpa;
void *vmcs;

void *msr_hva;
uint64_t msr_gpa;
void *msr;
};

struct vmx_pages *vcpu_alloc_vmx(struct kvm_vm *vm, vm_vaddr_t *p_vmx_gva);
bool prepare_for_vmx_operation(struct vmx_pages *vmx);
void prepare_vmcs(struct vmx_pages *vmx, void *guest_rip, void *guest_rsp);

#endif /* !SELFTEST_KVM_VMX_H */
71 changes: 42 additions & 29 deletions tools/testing/selftests/kvm/lib/vmx.c
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Original file line number Diff line number Diff line change
Expand Up @@ -13,47 +13,43 @@
#include "x86.h"
#include "vmx.h"

/* Create a default VM for VMX tests.
/* Allocate memory regions for nested VMX tests.
*
* Input Args:
* vcpuid - The id of the single VCPU to add to the VM.
* guest_code - The vCPU's entry point
* vm - The VM to allocate guest-virtual addresses in.
*
* Output Args: None
* Output Args:
* p_vmx_gva - The guest virtual address for the struct vmx_pages.
*
* Return:
* Pointer to opaque structure that describes the created VM.
* Pointer to structure with the addresses of the VMX areas.
*/
struct kvm_vm *
vm_create_default_vmx(uint32_t vcpuid, vmx_guest_code_t guest_code)
struct vmx_pages *
vcpu_alloc_vmx(struct kvm_vm *vm, vm_vaddr_t *p_vmx_gva)
{
struct kvm_cpuid2 *cpuid;
struct kvm_vm *vm;
vm_vaddr_t vmxon_vaddr;
vm_paddr_t vmxon_paddr;
vm_vaddr_t vmcs_vaddr;
vm_paddr_t vmcs_paddr;

vm = vm_create_default(vcpuid, (void *) guest_code);

/* Enable nesting in CPUID */
vcpu_set_cpuid(vm, vcpuid, kvm_get_supported_cpuid());
vm_vaddr_t vmx_gva = vm_vaddr_alloc(vm, getpagesize(), 0x10000, 0, 0);
struct vmx_pages *vmx = addr_gva2hva(vm, vmx_gva);

/* Setup of a region of guest memory for the vmxon region. */
vmxon_vaddr = vm_vaddr_alloc(vm, getpagesize(), 0, 0, 0);
vmxon_paddr = addr_gva2gpa(vm, vmxon_vaddr);
vmx->vmxon = (void *)vm_vaddr_alloc(vm, getpagesize(), 0x10000, 0, 0);
vmx->vmxon_hva = addr_gva2hva(vm, (uintptr_t)vmx->vmxon);
vmx->vmxon_gpa = addr_gva2gpa(vm, (uintptr_t)vmx->vmxon);

/* Setup of a region of guest memory for a vmcs. */
vmcs_vaddr = vm_vaddr_alloc(vm, getpagesize(), 0, 0, 0);
vmcs_paddr = addr_gva2gpa(vm, vmcs_vaddr);
vmx->vmcs = (void *)vm_vaddr_alloc(vm, getpagesize(), 0x10000, 0, 0);
vmx->vmcs_hva = addr_gva2hva(vm, (uintptr_t)vmx->vmcs);
vmx->vmcs_gpa = addr_gva2gpa(vm, (uintptr_t)vmx->vmcs);

vcpu_args_set(vm, vcpuid, 4, vmxon_vaddr, vmxon_paddr, vmcs_vaddr,
vmcs_paddr);
/* Setup of a region of guest memory for the MSR bitmap. */
vmx->msr = (void *)vm_vaddr_alloc(vm, getpagesize(), 0x10000, 0, 0);
vmx->msr_hva = addr_gva2hva(vm, (uintptr_t)vmx->msr);
vmx->msr_gpa = addr_gva2gpa(vm, (uintptr_t)vmx->msr);

return vm;
*p_vmx_gva = vmx_gva;
return vmx;
}

void prepare_for_vmx_operation(void)
bool prepare_for_vmx_operation(struct vmx_pages *vmx)
{
uint64_t feature_control;
uint64_t required;
Expand Down Expand Up @@ -88,12 +84,27 @@ void prepare_for_vmx_operation(void)
feature_control = rdmsr(MSR_IA32_FEATURE_CONTROL);
if ((feature_control & required) != required)
wrmsr(MSR_IA32_FEATURE_CONTROL, feature_control | required);

/* Enter VMX root operation. */
*(uint32_t *)(vmx->vmxon) = vmcs_revision();
if (vmxon(vmx->vmxon_gpa))
return false;

/* Load a VMCS. */
*(uint32_t *)(vmx->vmcs) = vmcs_revision();
if (vmclear(vmx->vmcs_gpa))
return false;

if (vmptrld(vmx->vmcs_gpa))
return false;

return true;
}

/*
* Initialize the control fields to the most basic settings possible.
*/
static inline void init_vmcs_control_fields(void)
static inline void init_vmcs_control_fields(struct vmx_pages *vmx)
{
vmwrite(VIRTUAL_PROCESSOR_ID, 0);
vmwrite(POSTED_INTR_NV, 0);
Expand All @@ -119,6 +130,8 @@ static inline void init_vmcs_control_fields(void)
vmwrite(CR4_GUEST_HOST_MASK, 0);
vmwrite(CR0_READ_SHADOW, get_cr0());
vmwrite(CR4_READ_SHADOW, get_cr4());

vmwrite(MSR_BITMAP, vmx->msr_gpa);
}

/*
Expand Down Expand Up @@ -235,9 +248,9 @@ static inline void init_vmcs_guest_state(void *rip, void *rsp)
vmwrite(GUEST_SYSENTER_EIP, vmreadz(HOST_IA32_SYSENTER_EIP));
}

void prepare_vmcs(void *guest_rip, void *guest_rsp)
void prepare_vmcs(struct vmx_pages *vmx, void *guest_rip, void *guest_rsp)
{
init_vmcs_control_fields();
init_vmcs_control_fields(vmx);
init_vmcs_host_state();
init_vmcs_guest_state(guest_rip, guest_rsp);
}
69 changes: 13 additions & 56 deletions tools/testing/selftests/kvm/vmx_tsc_adjust_test.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -46,11 +46,6 @@ enum {
PORT_DONE,
};

struct vmx_page {
vm_vaddr_t virt;
vm_paddr_t phys;
};

enum {
VMXON_PAGE = 0,
VMCS_PAGE,
Expand All @@ -67,9 +62,6 @@ struct kvm_single_msr {
/* The virtual machine object. */
static struct kvm_vm *vm;

/* Array of vmx_page descriptors that is shared with the guest. */
struct vmx_page *vmx_pages;

#define exit_to_l0(_port, _arg) do_exit_to_l0(_port, (unsigned long) (_arg))
static void do_exit_to_l0(uint16_t port, unsigned long arg)
{
Expand Down Expand Up @@ -105,7 +97,7 @@ static void l2_guest_code(void)
__asm__ __volatile__("vmcall");
}

static void l1_guest_code(struct vmx_page *vmx_pages)
static void l1_guest_code(struct vmx_pages *vmx_pages)
{
#define L2_GUEST_STACK_SIZE 64
unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE];
Expand All @@ -116,23 +108,14 @@ static void l1_guest_code(struct vmx_page *vmx_pages)
wrmsr(MSR_IA32_TSC, rdtsc() - TSC_ADJUST_VALUE);
check_ia32_tsc_adjust(-1 * TSC_ADJUST_VALUE);

prepare_for_vmx_operation();

/* Enter VMX root operation. */
*(uint32_t *)vmx_pages[VMXON_PAGE].virt = vmcs_revision();
GUEST_ASSERT(!vmxon(vmx_pages[VMXON_PAGE].phys));

/* Load a VMCS. */
*(uint32_t *)vmx_pages[VMCS_PAGE].virt = vmcs_revision();
GUEST_ASSERT(!vmclear(vmx_pages[VMCS_PAGE].phys));
GUEST_ASSERT(!vmptrld(vmx_pages[VMCS_PAGE].phys));
GUEST_ASSERT(prepare_for_vmx_operation(vmx_pages));

/* Prepare the VMCS for L2 execution. */
prepare_vmcs(l2_guest_code, &l2_guest_stack[L2_GUEST_STACK_SIZE]);
prepare_vmcs(vmx_pages, l2_guest_code,
&l2_guest_stack[L2_GUEST_STACK_SIZE]);
control = vmreadz(CPU_BASED_VM_EXEC_CONTROL);
control |= CPU_BASED_USE_MSR_BITMAPS | CPU_BASED_USE_TSC_OFFSETING;
vmwrite(CPU_BASED_VM_EXEC_CONTROL, control);
vmwrite(MSR_BITMAP, vmx_pages[MSR_BITMAP_PAGE].phys);
vmwrite(TSC_OFFSET, TSC_OFFSET_VALUE);

/* Jump into L2. First, test failure to load guest CR3. */
Expand All @@ -152,33 +135,6 @@ static void l1_guest_code(struct vmx_page *vmx_pages)
exit_to_l0(PORT_DONE, 0);
}

static void allocate_vmx_page(struct vmx_page *page)
{
vm_vaddr_t virt;

virt = vm_vaddr_alloc(vm, PAGE_SIZE, 0, 0, 0);
memset(addr_gva2hva(vm, virt), 0, PAGE_SIZE);

page->virt = virt;
page->phys = addr_gva2gpa(vm, virt);
}

static vm_vaddr_t allocate_vmx_pages(void)
{
vm_vaddr_t vmx_pages_vaddr;
int i;

vmx_pages_vaddr = vm_vaddr_alloc(
vm, sizeof(struct vmx_page) * NUM_VMX_PAGES, 0, 0, 0);

vmx_pages = (void *) addr_gva2hva(vm, vmx_pages_vaddr);

for (i = 0; i < NUM_VMX_PAGES; i++)
allocate_vmx_page(&vmx_pages[i]);

return vmx_pages_vaddr;
}

void report(int64_t val)
{
printf("IA32_TSC_ADJUST is %ld (%lld * TSC_ADJUST_VALUE + %lld).\n",
Expand All @@ -187,31 +143,32 @@ void report(int64_t val)

int main(int argc, char *argv[])
{
vm_vaddr_t vmx_pages_vaddr;
struct vmx_pages *vmx_pages;
vm_vaddr_t vmx_pages_gva;
struct kvm_cpuid_entry2 *entry = kvm_get_supported_cpuid_entry(1);

if (!(entry->ecx & CPUID_VMX)) {
fprintf(stderr, "nested VMX not enabled, skipping test\n");
exit(KSFT_SKIP);
}

vm = vm_create_default_vmx(VCPU_ID, (void *) l1_guest_code);
vm = vm_create_default(VCPU_ID, (void *) l1_guest_code);
vcpu_set_cpuid(vm, VCPU_ID, kvm_get_supported_cpuid());

/* Allocate VMX pages and shared descriptors (vmx_pages). */
vmx_pages_vaddr = allocate_vmx_pages();
vcpu_args_set(vm, VCPU_ID, 1, vmx_pages_vaddr);
vmx_pages = vcpu_alloc_vmx(vm, &vmx_pages_gva);
vcpu_args_set(vm, VCPU_ID, 1, vmx_pages_gva);

for (;;) {
volatile struct kvm_run *run = vcpu_state(vm, VCPU_ID);
struct kvm_regs regs;

vcpu_run(vm, VCPU_ID);
vcpu_regs_get(vm, VCPU_ID, &regs);
TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
"Got exit_reason other than KVM_EXIT_IO: %u (%s),\n",
"Got exit_reason other than KVM_EXIT_IO: %u (%s), rip=%lx\n",
run->exit_reason,
exit_reason_str(run->exit_reason));

vcpu_regs_get(vm, VCPU_ID, &regs);
exit_reason_str(run->exit_reason), regs.rip);

switch (run->io.port) {
case PORT_ABORT:
Expand Down

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