Commit 60325261 authored by Vipin Sharma's avatar Vipin Sharma Committed by Sean Christopherson
Browse files

KVM: selftests: Test Hyper-V extended hypercall exit to userspace 



Hyper-V extended hypercalls by default exit to userspace. Verify
userspace gets the call, update the result and then verify in guest
correct result is received.

Add KVM_EXIT_HYPERV to list of "known" hypercalls so errors generate
pretty strings.

Signed-off-by: default avatarVipin Sharma <vipinsh@google.com>
Reviewed-by: default avatarDavid Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20221212183720.4062037-14-vipinsh@google.com


[sean: add KVM_EXIT_HYPERV to exit_reasons_known]
Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
parent f6509201

tools/testing/selftests/kvm/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -67,6 +67,7 @@ TEST_GEN_PROGS_x86_64 += x86_64/fix_hypercall_test 
TEST_GEN_PROGS_x86_64 += x86_64/hyperv_clock

TEST_GEN_PROGS_x86_64 += x86_64/hyperv_cpuid

TEST_GEN_PROGS_x86_64 += x86_64/hyperv_evmcs

TEST_GEN_PROGS_x86_64 += x86_64/hyperv_extended_hypercalls

TEST_GEN_PROGS_x86_64 += x86_64/hyperv_features

TEST_GEN_PROGS_x86_64 += x86_64/hyperv_ipi

TEST_GEN_PROGS_x86_64 += x86_64/hyperv_svm_test

tools/testing/selftests/kvm/lib/kvm_util.c

+1 −0
Original line number Diff line number Diff line
@@ -1844,6 +1844,7 @@ static struct exit_reason { 
	{KVM_EXIT_X86_RDMSR, "RDMSR"},

	{KVM_EXIT_X86_WRMSR, "WRMSR"},

	{KVM_EXIT_XEN, "XEN"},

	{KVM_EXIT_HYPERV, "HYPERV"},

#ifdef KVM_EXIT_MEMORY_NOT_PRESENT

	{KVM_EXIT_MEMORY_NOT_PRESENT, "MEMORY_NOT_PRESENT"},

#endif

tools/testing/selftests/kvm/x86_64/hyperv_extended_hypercalls.c

0 → 100644
+97 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0-only

/*

 * Test Hyper-V extended hypercall, HV_EXT_CALL_QUERY_CAPABILITIES (0x8001),

 * exit to userspace and receive result in guest.

 *

 * Negative tests are present in hyperv_features.c

 *

 * Copyright 2022 Google LLC

 * Author: Vipin Sharma <vipinsh@google.com>

 */



#include "kvm_util.h"

#include "processor.h"

#include "hyperv.h"



/* Any value is fine */

#define EXT_CAPABILITIES 0xbull



static void guest_code(vm_paddr_t in_pg_gpa, vm_paddr_t out_pg_gpa,

		       vm_vaddr_t out_pg_gva)

{

	uint64_t *output_gva;



	wrmsr(HV_X64_MSR_GUEST_OS_ID, HYPERV_LINUX_OS_ID);

	wrmsr(HV_X64_MSR_HYPERCALL, in_pg_gpa);



	output_gva = (uint64_t *)out_pg_gva;



	hyperv_hypercall(HV_EXT_CALL_QUERY_CAPABILITIES, in_pg_gpa, out_pg_gpa);



	/* TLFS states output will be a uint64_t value */

	GUEST_ASSERT_EQ(*output_gva, EXT_CAPABILITIES);



	GUEST_DONE();

}



int main(void)

{

	vm_vaddr_t hcall_out_page;

	vm_vaddr_t hcall_in_page;

	struct kvm_vcpu *vcpu;

	struct kvm_run *run;

	struct kvm_vm *vm;

	uint64_t *outval;

	struct ucall uc;



	/* Verify if extended hypercalls are supported */

	if (!kvm_cpuid_has(kvm_get_supported_hv_cpuid(),

			   HV_ENABLE_EXTENDED_HYPERCALLS)) {

		print_skip("Extended calls not supported by the kernel");

		exit(KSFT_SKIP);

	}



	vm = vm_create_with_one_vcpu(&vcpu, guest_code);

	run = vcpu->run;

	vcpu_set_hv_cpuid(vcpu);



	/* Hypercall input */

	hcall_in_page = vm_vaddr_alloc_pages(vm, 1);

	memset(addr_gva2hva(vm, hcall_in_page), 0x0, vm->page_size);



	/* Hypercall output */

	hcall_out_page = vm_vaddr_alloc_pages(vm, 1);

	memset(addr_gva2hva(vm, hcall_out_page), 0x0, vm->page_size);



	vcpu_args_set(vcpu, 3, addr_gva2gpa(vm, hcall_in_page),

		      addr_gva2gpa(vm, hcall_out_page), hcall_out_page);



	vcpu_run(vcpu);



	TEST_ASSERT(run->exit_reason == KVM_EXIT_HYPERV,

		    "Unexpected exit reason: %u (%s)",

		    run->exit_reason, exit_reason_str(run->exit_reason));



	outval = addr_gpa2hva(vm, run->hyperv.u.hcall.params[1]);

	*outval = EXT_CAPABILITIES;

	run->hyperv.u.hcall.result = HV_STATUS_SUCCESS;



	vcpu_run(vcpu);



	TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,

		    "Unexpected exit reason: %u (%s)",

		    run->exit_reason, exit_reason_str(run->exit_reason));



	switch (get_ucall(vcpu, &uc)) {

	case UCALL_ABORT:

		REPORT_GUEST_ASSERT_2(uc, "arg1 = %ld, arg2 = %ld");

		break;

	case UCALL_DONE:

		break;

	default:

		TEST_FAIL("Unhandled ucall: %ld", uc.cmd);

	}



	kvm_vm_free(vm);

	return 0;

}