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.
By default, vms are created with in-kernel APIC support in KVM selftests.
VM needs to be created without in-kernel APIC support for this test, so
that HLT will exit to userspace. To do so, __vm_create() is modified to not
call KVM_CREATE_IRQCHIP ioctl while creating vm.
Add a test case to test KVM_X86_DISABLE_EXITS_HLT functionality.
Patch 1, 2 -> Preparatory patches to add the KVM_X86_DISABLE_EXITS_HLT test
case
Patch 3 -> Adds a test case for KVM_X86_DISABLE_EXITS_HLT
Testing done:
Tested KVM_X86_DISABLE_EXITS_HLT test case on AMD and Intel machines.
v1 -> v2
- Extended @shape to allow creation of VM without in-kernel APIC support
(Andrew Jones)
- Changed the test case based on Andrew's comments.
- Few more changes to the test case to pass the address of the flag on
which guest waits to execute HLT.
Manali Shukla (3):
KVM: selftests: Add safe_halt() and cli() helpers to common code
KVM: selftests: Extend @shape to allow creation of VM without
in-kernel APIC
KVM: selftests: Add a test case for KVM_X86_DISABLE_EXITS_HLT
tools/testing/selftests/kvm/Makefile | 1 +
.../selftests/kvm/include/kvm_util_base.h | 17 ++-
.../selftests/kvm/include/x86_64/processor.h | 17 +++
tools/testing/selftests/kvm/lib/kvm_util.c | 1 +
.../selftests/kvm/lib/x86_64/processor.c | 4 +-
.../kvm/x86_64/halt_disable_exit_test.c | 120 ++++++++++++++++++
6 files changed, 158 insertions(+), 2 deletions(-)
create mode 100644 tools/testing/selftests/kvm/x86_64/halt_disable_exit_test.c
base-commit: e9da6f08edb0bd4c621165496778d77a222e1174
--
2.34.1
