| Message ID | 20240401152032.4284-4-manali.shukla@amd.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | Add a test case for KVM_X86_DISABLE_EXIT | expand |
On 4/1/24 08:20, Manali Shukla wrote: > By default, HLT instruction executed by guest is intercepted by hypervisor. > However, KVM_CAP_X86_DISABLE_EXITS capability can be used to not intercept > HLT by setting KVM_X86_DISABLE_EXITS_HLT. > > Add a test case to test KVM_X86_DISABLE_EXITS_HLT functionality. > > Suggested-by: Sean Christopherson <seanjc@google.com> > Signed-off-by: Manali Shukla <manali.shukla@amd.com> > --- > tools/testing/selftests/kvm/Makefile | 1 + > .../kvm/x86_64/halt_disable_exit_test.c | 119 ++++++++++++++++++ > 2 files changed, 120 insertions(+) > create mode 100644 tools/testing/selftests/kvm/x86_64/halt_disable_exit_test.c > > diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile > index c75251d5c97c..9f72abb95d2e 100644 > --- a/tools/testing/selftests/kvm/Makefile > +++ b/tools/testing/selftests/kvm/Makefile > @@ -89,6 +89,7 @@ TEST_GEN_PROGS_x86_64 += x86_64/set_sregs_test > TEST_GEN_PROGS_x86_64 += x86_64/smaller_maxphyaddr_emulation_test > TEST_GEN_PROGS_x86_64 += x86_64/smm_test > TEST_GEN_PROGS_x86_64 += x86_64/state_test > +TEST_GEN_PROGS_x86_64 += x86_64/halt_disable_exit_test > TEST_GEN_PROGS_x86_64 += x86_64/vmx_preemption_timer_test > TEST_GEN_PROGS_x86_64 += x86_64/svm_vmcall_test > TEST_GEN_PROGS_x86_64 += x86_64/svm_int_ctl_test > diff --git a/tools/testing/selftests/kvm/x86_64/halt_disable_exit_test.c b/tools/testing/selftests/kvm/x86_64/halt_disable_exit_test.c > new file mode 100644 > index 000000000000..4cc6a09906a2 > --- /dev/null > +++ b/tools/testing/selftests/kvm/x86_64/halt_disable_exit_test.c > @@ -0,0 +1,119 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * KVM disable halt exit test > + * > + * Copyright (C) 2024 Advanced Micro Devices, Inc. > + */ > +#include <pthread.h> > +#include <signal.h> > +#include "kvm_util.h" > +#include "processor.h" > +#include "test_util.h" > + > +#define SIG_IPI SIGUSR1 > +static pthread_t task_thread, vcpu_thread; > + > +static void guest_code(uint64_t *is_hlt_exec) > +{ > + while (!READ_ONCE(*is_hlt_exec)) > + ; > + > + safe_halt(); May I confirm if this selftest works on nested L1 VM as a hypervisor? Thank you very much! Dongli Zhang
On 4/1/2024 10:29 PM, Dongli Zhang wrote: > > > On 4/1/24 08:20, Manali Shukla wrote: >> By default, HLT instruction executed by guest is intercepted by hypervisor. >> However, KVM_CAP_X86_DISABLE_EXITS capability can be used to not intercept >> HLT by setting KVM_X86_DISABLE_EXITS_HLT. >> >> Add a test case to test KVM_X86_DISABLE_EXITS_HLT functionality. >> >> Suggested-by: Sean Christopherson <seanjc@google.com> >> Signed-off-by: Manali Shukla <manali.shukla@amd.com> >> --- >> tools/testing/selftests/kvm/Makefile | 1 + >> .../kvm/x86_64/halt_disable_exit_test.c | 119 ++++++++++++++++++ >> 2 files changed, 120 insertions(+) >> create mode 100644 tools/testing/selftests/kvm/x86_64/halt_disable_exit_test.c >> >> diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile >> index c75251d5c97c..9f72abb95d2e 100644 >> --- a/tools/testing/selftests/kvm/Makefile >> +++ b/tools/testing/selftests/kvm/Makefile >> @@ -89,6 +89,7 @@ TEST_GEN_PROGS_x86_64 += x86_64/set_sregs_test >> TEST_GEN_PROGS_x86_64 += x86_64/smaller_maxphyaddr_emulation_test >> TEST_GEN_PROGS_x86_64 += x86_64/smm_test >> TEST_GEN_PROGS_x86_64 += x86_64/state_test >> +TEST_GEN_PROGS_x86_64 += x86_64/halt_disable_exit_test >> TEST_GEN_PROGS_x86_64 += x86_64/vmx_preemption_timer_test >> TEST_GEN_PROGS_x86_64 += x86_64/svm_vmcall_test >> TEST_GEN_PROGS_x86_64 += x86_64/svm_int_ctl_test >> diff --git a/tools/testing/selftests/kvm/x86_64/halt_disable_exit_test.c b/tools/testing/selftests/kvm/x86_64/halt_disable_exit_test.c >> new file mode 100644 >> index 000000000000..4cc6a09906a2 >> --- /dev/null >> +++ b/tools/testing/selftests/kvm/x86_64/halt_disable_exit_test.c >> @@ -0,0 +1,119 @@ >> +// SPDX-License-Identifier: GPL-2.0-only >> +/* >> + * KVM disable halt exit test >> + * >> + * Copyright (C) 2024 Advanced Micro Devices, Inc. >> + */ >> +#include <pthread.h> >> +#include <signal.h> >> +#include "kvm_util.h" >> +#include "processor.h" >> +#include "test_util.h" >> + >> +#define SIG_IPI SIGUSR1 >> +static pthread_t task_thread, vcpu_thread; >> + >> +static void guest_code(uint64_t *is_hlt_exec) >> +{ >> + while (!READ_ONCE(*is_hlt_exec)) >> + ; >> + >> + safe_halt(); > > May I confirm if this selftest works on nested L1 VM as a hypervisor? Yes, this selftest works on nested L1 VM. > > Thank you very much! > > Dongli Zhang
diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile index c75251d5c97c..9f72abb95d2e 100644 --- a/tools/testing/selftests/kvm/Makefile +++ b/tools/testing/selftests/kvm/Makefile @@ -89,6 +89,7 @@ TEST_GEN_PROGS_x86_64 += x86_64/set_sregs_test TEST_GEN_PROGS_x86_64 += x86_64/smaller_maxphyaddr_emulation_test TEST_GEN_PROGS_x86_64 += x86_64/smm_test TEST_GEN_PROGS_x86_64 += x86_64/state_test +TEST_GEN_PROGS_x86_64 += x86_64/halt_disable_exit_test TEST_GEN_PROGS_x86_64 += x86_64/vmx_preemption_timer_test TEST_GEN_PROGS_x86_64 += x86_64/svm_vmcall_test TEST_GEN_PROGS_x86_64 += x86_64/svm_int_ctl_test diff --git a/tools/testing/selftests/kvm/x86_64/halt_disable_exit_test.c b/tools/testing/selftests/kvm/x86_64/halt_disable_exit_test.c new file mode 100644 index 000000000000..4cc6a09906a2 --- /dev/null +++ b/tools/testing/selftests/kvm/x86_64/halt_disable_exit_test.c @@ -0,0 +1,119 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * KVM disable halt exit test + * + * Copyright (C) 2024 Advanced Micro Devices, Inc. + */ +#include <pthread.h> +#include <signal.h> +#include "kvm_util.h" +#include "processor.h" +#include "test_util.h" + +#define SIG_IPI SIGUSR1 +static pthread_t task_thread, vcpu_thread; + +static void guest_code(uint64_t *is_hlt_exec) +{ + while (!READ_ONCE(*is_hlt_exec)) + ; + + safe_halt(); + GUEST_DONE(); +} + +static void *task_worker(void *arg) +{ + uint64_t *is_hlt_exec = (uint64_t *)arg; + + usleep(100000); + WRITE_ONCE(*is_hlt_exec, 1); + pthread_kill(vcpu_thread, SIG_IPI); + return 0; +} + +static void *vcpu_worker(void *arg) +{ + int ret; + int sig = -1; + struct kvm_vcpu *vcpu = (struct kvm_vcpu *) arg; + struct kvm_run *run; + + struct kvm_signal_mask *sigmask = alloca(offsetof(struct kvm_signal_mask, sigset) + + sizeof(sigset_t)); + sigset_t *sigset = (sigset_t *) &sigmask->sigset; + + /* + * SIG_IPI is unblocked atomically while in KVM_RUN. It causes the + * ioctl to return with -EINTR, but it is still pending and we need + * to accept it with the sigwait. + */ + sigmask->len = 8; + pthread_sigmask(0, NULL, sigset); + sigdelset(sigset, SIG_IPI); + vcpu_ioctl(vcpu, KVM_SET_SIGNAL_MASK, sigmask); + sigemptyset(sigset); + sigaddset(sigset, SIG_IPI); + run = vcpu->run; + +again: + ret = __vcpu_run(vcpu); + TEST_ASSERT_EQ(errno, EINTR); + + if (ret == -1 && errno == EINTR) { + sigwait(sigset, &sig); + assert(sig == SIG_IPI); + TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_INTR); + goto again; + } + + if (run->exit_reason == KVM_EXIT_HLT) + TEST_FAIL("Expected KVM_EXIT_INTR, got KVM_EXIT_HLT"); + + TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_IO); + return 0; +} + +int main(int argc, char *argv[]) +{ + vm_vaddr_t hlt_vm_addr; + + struct kvm_vm *vm; + struct kvm_vcpu *vcpu; + uint64_t *host_hlt_addr; + void *retval; + sigset_t sigset; + int ret; + + TEST_REQUIRE(kvm_has_cap(KVM_CAP_X86_DISABLE_EXITS)); + + /* Create a VM without in kernel APIC support */ + vm = __vm_create(VM_SHAPE_FLAGS(NO_IRQCHIP), 1, 0); + vm_enable_cap(vm, KVM_CAP_X86_DISABLE_EXITS, KVM_X86_DISABLE_EXITS_HLT); + vcpu = vm_vcpu_add(vm, 0, guest_code); + + + hlt_vm_addr = vm_vaddr_alloc_page(vm); + host_hlt_addr = (uint64_t *)addr_gva2hva(vm, hlt_vm_addr); + vcpu_args_set(vcpu, 1, hlt_vm_addr); + + /* Ensure that vCPU threads start with SIG_IPI blocked. */ + sigemptyset(&sigset); + sigaddset(&sigset, SIG_IPI); + pthread_sigmask(SIG_BLOCK, &sigset, NULL); + + ret = pthread_create(&vcpu_thread, NULL, vcpu_worker, vcpu); + TEST_ASSERT(ret == 0, "pthread_create vcpu thread failed errno=%d", errno); + + ret = pthread_create(&task_thread, NULL, task_worker, host_hlt_addr); + TEST_ASSERT(ret == 0, "pthread_create task thread failed errno=%d", errno); + + ret = pthread_join(vcpu_thread, &retval); + TEST_ASSERT(ret == 0, "pthread_join on vcpu thread failed with errno=%d", ret); + + ret = pthread_join(task_thread, &retval); + TEST_ASSERT(ret == 0, "pthread_join on task thread failed with errno=%d", ret); + + kvm_vm_free(vm); + return 0; +}
By default, HLT instruction executed by guest is intercepted by hypervisor. However, KVM_CAP_X86_DISABLE_EXITS capability can be used to not intercept HLT by setting KVM_X86_DISABLE_EXITS_HLT. Add a test case to test KVM_X86_DISABLE_EXITS_HLT functionality. Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Manali Shukla <manali.shukla@amd.com> --- tools/testing/selftests/kvm/Makefile | 1 + .../kvm/x86_64/halt_disable_exit_test.c | 119 ++++++++++++++++++ 2 files changed, 120 insertions(+) create mode 100644 tools/testing/selftests/kvm/x86_64/halt_disable_exit_test.c