Re: [PATCH v2 3/3] KVM: selftests: Add a test case for KVM_X86_DISABLE_EXITS_HLT

[Manali Shukla <manali.shukla@amd.com>]

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