// SPDX-License-Identifier: GPL-2.0-only
/*
* xen_vmcall_test
*
* Copyright © 2020 Amazon.com, Inc. or its affiliates.
*
* Userspace hypercall testing
*/
#include "test_util.h"
#include "kvm_util.h"
#include "processor.h"
#include "hyperv.h"
#define HCALL_REGION_GPA 0xc0000000ULL
#define HCALL_REGION_SLOT 10
#define INPUTVALUE 17
#define ARGVALUE(x) (0xdeadbeef5a5a0000UL + x)
#define RETVALUE 0xcafef00dfbfbffffUL
#define XEN_HYPERCALL_MSR 0x40000200
#define HV_GUEST_OS_ID_MSR 0x40000000
#define HV_HYPERCALL_MSR 0x40000001
#define HVCALL_SIGNAL_EVENT 0x005d
#define HV_STATUS_INVALID_ALIGNMENT 4
static void guest_code(void)
{
unsigned long rax = INPUTVALUE;
unsigned long rdi = ARGVALUE(1);
unsigned long rsi = ARGVALUE(2);
unsigned long rdx = ARGVALUE(3);
unsigned long rcx;
register unsigned long r10 __asm__("r10") = ARGVALUE(4);
register unsigned long r8 __asm__("r8") = ARGVALUE(5);
register unsigned long r9 __asm__("r9") = ARGVALUE(6);
/* First a direct invocation of 'vmcall' */
__asm__ __volatile__("vmcall" :
"=a"(rax) :
"a"(rax), "D"(rdi), "S"(rsi), "d"(rdx),
"r"(r10), "r"(r8), "r"(r9));
GUEST_ASSERT(rax == RETVALUE);
/* Fill in the Xen hypercall page */
__asm__ __volatile__("wrmsr" : : "c" (XEN_HYPERCALL_MSR),
"a" (HCALL_REGION_GPA & 0xffffffff),
"d" (HCALL_REGION_GPA >> 32));
/* Set Hyper-V Guest OS ID */
__asm__ __volatile__("wrmsr" : : "c" (HV_GUEST_OS_ID_MSR),
"a" (0x5a), "d" (0));
/* Hyper-V hypercall page */
u64 msrval = HCALL_REGION_GPA + PAGE_SIZE + 1;
__asm__ __volatile__("wrmsr" : : "c" (HV_HYPERCALL_MSR),
"a" (msrval & 0xffffffff),
"d" (msrval >> 32));
/* Invoke a Xen hypercall */
__asm__ __volatile__("call *%1" : "=a"(rax) :
"r"(HCALL_REGION_GPA + INPUTVALUE * 32),
"a"(rax), "D"(rdi), "S"(rsi), "d"(rdx),
"r"(r10), "r"(r8), "r"(r9));
GUEST_ASSERT(rax == RETVALUE);
/* Invoke a Hyper-V hypercall */
rax = 0;
rcx = HVCALL_SIGNAL_EVENT; /* code */
rdx = 0x5a5a5a5a; /* ingpa (badly aligned) */
__asm__ __volatile__("call *%1" : "=a"(rax) :
"r"(HCALL_REGION_GPA + PAGE_SIZE),
"a"(rax), "c"(rcx), "d"(rdx),
"r"(r8));
GUEST_ASSERT(rax == HV_STATUS_INVALID_ALIGNMENT);
GUEST_DONE();
}
int main(int argc, char *argv[])
{
unsigned int xen_caps;
struct kvm_vcpu *vcpu;
struct kvm_vm *vm;
xen_caps = kvm_check_cap(KVM_CAP_XEN_HVM);
TEST_REQUIRE(xen_caps & KVM_XEN_HVM_CONFIG_INTERCEPT_HCALL);
vm = vm_create_with_one_vcpu(&vcpu, guest_code);
vcpu_set_hv_cpuid(vcpu);
struct kvm_xen_hvm_config hvmc = {
.flags = KVM_XEN_HVM_CONFIG_INTERCEPT_HCALL,
.msr = XEN_HYPERCALL_MSR,
};
vm_ioctl(vm, KVM_XEN_HVM_CONFIG, &hvmc);
/* Map a region for the hypercall pages */
vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS,
HCALL_REGION_GPA, HCALL_REGION_SLOT, 2, 0);
virt_map(vm, HCALL_REGION_GPA, HCALL_REGION_GPA, 2);
for (;;) {
volatile struct kvm_run *run = vcpu->run;
struct ucall uc;
vcpu_run(vcpu);
if (run->exit_reason == KVM_EXIT_XEN) {
TEST_ASSERT_EQ(run->xen.type, KVM_EXIT_XEN_HCALL);
TEST_ASSERT_EQ(run->xen.u.hcall.cpl, 0);
TEST_ASSERT_EQ(run->xen.u.hcall.longmode, 1);
TEST_ASSERT_EQ(run->xen.u.hcall.input, INPUTVALUE);
TEST_ASSERT_EQ(run->xen.u.hcall.params[0], ARGVALUE(1));
TEST_ASSERT_EQ(run->xen.u.hcall.params[1], ARGVALUE(2));
TEST_ASSERT_EQ(run->xen.u.hcall.params[2], ARGVALUE(3));
TEST_ASSERT_EQ(run->xen.u.hcall.params[3], ARGVALUE(4));
TEST_ASSERT_EQ(run->xen.u.hcall.params[4], ARGVALUE(5));
TEST_ASSERT_EQ(run->xen.u.hcall.params[5], ARGVALUE(6));
run->xen.u.hcall.result = RETVALUE;
continue;
}
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 0x%lx.", uc.cmd);
}
}
done:
kvm_vm_free(vm);
return 0;
}