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KVM: selftests: Use exception fixup for #UD/#GP Hyper-V MSR/hcall tests

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Use exception fixup to verify VMCALL/RDMSR/WRMSR fault as expected in the
Hyper-V Features test.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220608224516.3788274-5-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Sean Christopherson 2022-06-08 22:45:15 +00:00 committed by Paolo Bonzini
parent 9f88d062c3
commit cc5851c6be
1 changed files with 31 additions and 82 deletions
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113
tools/testing/selftests/kvm/x86_64/hyperv_features.c
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@ -15,75 +15,20 @@
#define LINUX_OS_ID ((u64)0x8100 << 48)
extern unsigned char rdmsr_start;
extern unsigned char rdmsr_end;
static u64 do_rdmsr(u32 idx)
static inline uint8_t hypercall(u64 control, vm_vaddr_t input_address,
vm_vaddr_t output_address, uint64_t *hv_status)
{
u32 lo, hi;
uint8_t vector;
asm volatile("rdmsr_start: rdmsr;"
"rdmsr_end:"
: "=a"(lo), "=c"(hi)
: "c"(idx));
return (((u64) hi) << 32) | lo;
}
extern unsigned char wrmsr_start;
extern unsigned char wrmsr_end;
static void do_wrmsr(u32 idx, u64 val)
{
u32 lo, hi;
lo = val;
hi = val >> 32;
asm volatile("wrmsr_start: wrmsr;"
"wrmsr_end:"
: : "a"(lo), "c"(idx), "d"(hi));
}
static int nr_gp;
static int nr_ud;
static inline u64 hypercall(u64 control, vm_vaddr_t input_address,
vm_vaddr_t output_address)
{
u64 hv_status;
asm volatile("mov %3, %%r8\n"
"vmcall"
: "=a" (hv_status),
"+c" (control), "+d" (input_address)
: "r" (output_address)
: "cc", "memory", "r8", "r9", "r10", "r11");
return hv_status;
}
static void guest_gp_handler(struct ex_regs *regs)
{
unsigned char *rip = (unsigned char *)regs->rip;
bool r, w;
r = rip == &rdmsr_start;
w = rip == &wrmsr_start;
GUEST_ASSERT(r || w);
nr_gp++;
if (r)
regs->rip = (uint64_t)&rdmsr_end;
else
regs->rip = (uint64_t)&wrmsr_end;
}
static void guest_ud_handler(struct ex_regs *regs)
{
nr_ud++;
regs->rip += 3;
/* Note both the hypercall and the "asm safe" clobber r9-r11. */
asm volatile("mov %[output_address], %%r8\n\t"
KVM_ASM_SAFE("vmcall")
: "=a" (*hv_status),
"+c" (control), "+d" (input_address),
KVM_ASM_SAFE_OUTPUTS(vector)
: [output_address] "r"(output_address)
: "cc", "memory", "r8", KVM_ASM_SAFE_CLOBBERS);
return vector;
}
struct msr_data {
@ -101,31 +46,33 @@ struct hcall_data {
static void guest_msr(struct msr_data *msr)
{
uint64_t ignored;
uint8_t vector;
GUEST_ASSERT(msr->idx);
WRITE_ONCE(nr_gp, 0);
if (!msr->write)
do_rdmsr(msr->idx);
vector = rdmsr_safe(msr->idx, &ignored);
else
do_wrmsr(msr->idx, msr->write_val);
vector = wrmsr_safe(msr->idx, msr->write_val);
if (msr->available)
GUEST_ASSERT(READ_ONCE(nr_gp) == 0);
GUEST_ASSERT_2(!vector, msr->idx, vector);
else
GUEST_ASSERT(READ_ONCE(nr_gp) == 1);
GUEST_ASSERT_2(vector == GP_VECTOR, msr->idx, vector);
GUEST_DONE();
}
static void guest_hcall(vm_vaddr_t pgs_gpa, struct hcall_data *hcall)
{
u64 res, input, output;
uint8_t vector;
GUEST_ASSERT(hcall->control);
wrmsr(HV_X64_MSR_GUEST_OS_ID, LINUX_OS_ID);
wrmsr(HV_X64_MSR_HYPERCALL, pgs_gpa);
nr_ud = 0;
if (!(hcall->control & HV_HYPERCALL_FAST_BIT)) {
input = pgs_gpa;
output = pgs_gpa + 4096;
@ -133,12 +80,14 @@ static void guest_hcall(vm_vaddr_t pgs_gpa, struct hcall_data *hcall)
input = output = 0;
}
res = hypercall(hcall->control, input, output);
vector = hypercall(hcall->control, input, output, &res);
if (hcall->ud_expected)
GUEST_ASSERT(nr_ud == 1);
GUEST_ASSERT_2(vector == UD_VECTOR, hcall->control, vector);
else
GUEST_ASSERT(res == hcall->expect);
GUEST_ASSERT_2(!vector, hcall->control, vector);
GUEST_ASSERT_2(!hcall->ud_expected || res == hcall->expect,
hcall->expect, res);
GUEST_DONE();
}
@ -192,7 +141,6 @@ static void guest_test_msrs_access(void)
vm_init_descriptor_tables(vm);
vcpu_init_descriptor_tables(vcpu);
vm_install_exception_handler(vm, GP_VECTOR, guest_gp_handler);
run = vcpu->run;
@ -499,8 +447,9 @@ static void guest_test_msrs_access(void)
switch (get_ucall(vcpu, &uc)) {
case UCALL_ABORT:
TEST_FAIL("%s at %s:%ld", (const char *)uc.args[0],
__FILE__, uc.args[1]);
TEST_FAIL("%s at %s:%ld, MSR = %lx, vector = %lx",
(const char *)uc.args[0], __FILE__,
uc.args[1], uc.args[2], uc.args[3]);
return;
case UCALL_DONE:
break;
@ -540,7 +489,6 @@ static void guest_test_hcalls_access(void)
vm_init_descriptor_tables(vm);
vcpu_init_descriptor_tables(vcpu);
vm_install_exception_handler(vm, UD_VECTOR, guest_ud_handler);
/* Hypercall input/output */
hcall_page = vm_vaddr_alloc_pages(vm, 2);
@ -670,8 +618,9 @@ static void guest_test_hcalls_access(void)
switch (get_ucall(vcpu, &uc)) {
case UCALL_ABORT:
TEST_FAIL("%s at %s:%ld", (const char *)uc.args[0],
__FILE__, uc.args[1]);
TEST_FAIL("%s at %s:%ld, arg1 = %lx, arg2 = %lx",
(const char *)uc.args[0], __FILE__,
uc.args[1], uc.args[2], uc.args[3]);
return;
case UCALL_DONE:
break;