linux.git/tools/testing/selftests/kvm/Makefile, branch v5.14

KVM: selftests: Introduce access_tracking_perf_test

2021-07-27T20:59:00+00:00

This test measures the performance effects of KVM's access tracking.
Access tracking is driven by the MMU notifiers test_young, clear_young,
and clear_flush_young. These notifiers do not have a direct userspace
API, however the clear_young notifier can be triggered by marking a
pages as idle in /sys/kernel/mm/page_idle/bitmap. This test leverages
that mechanism to enable access tracking on guest memory.

To measure performance this test runs a VM with a configurable number of
vCPUs that each touch every page in disjoint regions of memory.
Performance is measured in the time it takes all vCPUs to finish
touching their predefined region.

Example invocation:

  $ ./access_tracking_perf_test -v 8
  Testing guest mode: PA-bits:ANY, VA-bits:48,  4K pages
  guest physical test memory offset: 0xffdfffff000

  Populating memory             : 1.337752570s
  Writing to populated memory   : 0.010177640s
  Reading from populated memory : 0.009548239s
  Mark memory idle              : 23.973131748s
  Writing to idle memory        : 0.063584496s
  Mark memory idle              : 24.924652964s
  Reading from idle memory      : 0.062042814s

Breaking down the results:

 * "Populating memory": The time it takes for all vCPUs to perform the
   first write to every page in their region.

 * "Writing to populated memory" / "Reading from populated memory": The
   time it takes for all vCPUs to write and read to every page in their
   region after it has been populated. This serves as a control for the
   later results.

 * "Mark memory idle": The time it takes for every vCPU to mark every
   page in their region as idle through page_idle.

 * "Writing to idle memory" / "Reading from idle memory": The time it
   takes for all vCPUs to write and read to every page in their region
   after it has been marked idle.

This test should be portable across architectures but it is only enabled
for x86_64 since that's all I have tested.

Reviewed-by: Ben Gardon 
Signed-off-by: David Matlack 
Message-Id: <20210713220957.3493520-7-dmatlack@google.com>
Signed-off-by: Paolo Bonzini

Merge tag 'kvmarm-5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

2021-06-25T15:24:24+00:00

KVM/arm64 updates for v5.14.

- Add MTE support in guests, complete with tag save/restore interface
- Reduce the impact of CMOs by moving them in the page-table code
- Allow device block mappings at stage-2
- Reduce the footprint of the vmemmap in protected mode
- Support the vGIC on dumb systems such as the Apple M1
- Add selftest infrastructure to support multiple configuration
  and apply that to PMU/non-PMU setups
- Add selftests for the debug architecture
- The usual crop of PMU fixes

selftests: kvm: Allows userspace to handle emulation errors.

2021-06-24T22:00:48+00:00

This test exercises the feature KVM_CAP_EXIT_ON_EMULATION_FAILURE.  When
enabled, errors in the in-kernel instruction emulator are forwarded to
userspace with the instruction bytes stored in the exit struct for
KVM_EXIT_INTERNAL_ERROR.  So, when the guest attempts to emulate an
'flds' instruction, which isn't able to be emulated in KVM, instead
of failing, KVM sends the instruction to userspace to handle.

For this test to work properly the module parameter
'allow_smaller_maxphyaddr' has to be set.

Signed-off-by: Aaron Lewis 
Reviewed-by: Jim Mattson 
Message-Id: <20210510144834.658457-3-aaronlewis@google.com>
Signed-off-by: Paolo Bonzini

KVM: selftests: Add selftest for KVM statistics data binary interface

2021-06-24T22:00:26+00:00

Add selftest to check KVM stats descriptors validity.

Reviewed-by: David Matlack 
Reviewed-by: Ricardo Koller 
Reviewed-by: Krish Sadhukhan 
Tested-by: Fuad Tabba  #arm64
Signed-off-by: Jing Zhang 
Message-Id: <20210618222709.1858088-7-jingzhangos@google.com>
Signed-off-by: Paolo Bonzini

KVM: sefltests: Add x86-64 test to verify MMU reacts to CPUID updates

2021-06-24T15:47:56+00:00

Add an x86-only test to verify that x86's MMU reacts to CPUID updates
that impact the MMU.  KVM has had multiple bugs where it fails to
reconfigure the MMU after the guest's vCPU model changes.

Sadly, this test is effectively limited to shadow paging because the
hardware page walk handler doesn't support software disabling of GBPAGES
support, and KVM doesn't manually walk the GVA->GPA on faults for
performance reasons (doing so would large defeat the benefits of TDP).

Don't require !TDP for the tests as there is still value in running the
tests with TDP, even though the tests will fail (barring KVM hacks).
E.g. KVM should not completely explode if MAXPHYADDR results in KVM using
4-level vs. 5-level paging for the guest.

Signed-off-by: Sean Christopherson 
Message-Id: <20210622200529.3650424-20-seanjc@google.com>
Signed-off-by: Paolo Bonzini

Merge branch kvm-arm64/selftest/sysreg-list-fix into kvmarm-master/next

2021-06-22T07:53:56+00:00

Selftest updates from Andrew Jones, fixing the sysgreg list
expectations by dealing with multiple configurations, such
as with or without a PMU.

* kvm-arm64/selftest/sysreg-list-fix:
  KVM: arm64: Update MAINTAINERS to include selftests
  KVM: arm64: selftests: get-reg-list: Split base and pmu registers
  KVM: arm64: selftests: get-reg-list: Remove get-reg-list-sve
  KVM: arm64: selftests: get-reg-list: Provide config selection option
  KVM: arm64: selftests: get-reg-list: Prepare to run multiple configs at once
  KVM: arm64: selftests: get-reg-list: Introduce vcpu configs

KVM: arm64: selftests: get-reg-list: Remove get-reg-list-sve

2021-06-22T07:51:28+00:00

Now that we can easily run the test for multiple vcpu configs, let's
merge get-reg-list and get-reg-list-sve into just get-reg-list. We
also add a final change to make it more possible to run multiple
tests, which is to fork the test, rather than directly run it. That
allows a test to fail, but subsequent tests can still run.

Signed-off-by: Andrew Jones 
Reviewed-by: Ricardo Koller 
Signed-off-by: Marc Zyngier 
Link: https://lore.kernel.org/r/20210531103344.29325-5-drjones@redhat.com

KVM: selftests: Introduce hyperv_features test

2021-06-17T17:09:46+00:00

The initial implementation of the test only tests that access to Hyper-V
MSRs and hypercalls is in compliance with guest visible CPUID feature bits.

Signed-off-by: Vitaly Kuznetsov 
Signed-off-by: Paolo Bonzini 
Message-Id: <20210521095204.2161214-31-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini

KVM: selftests: Hoist APIC functions out of individual tests

2021-06-17T17:09:32+00:00

Move the APIC functions into the library to encourage code reuse and
to avoid unintended deviations.

Signed-off-by: Jim Mattson 
Reviewed-by: Oliver Upton 
Message-Id: <20210604172611.281819-10-jmattson@google.com>
Signed-off-by: Paolo Bonzini

KVM: selftests: x86: Add vmx_nested_tsc_scaling_test

2021-06-17T17:09:30+00:00

Test that nested TSC scaling works as expected with both L1 and L2
scaled.

Signed-off-by: Ilias Stamatis 
Reviewed-by: Maxim Levitsky 
Message-Id: <20210526184418.28881-12-ilstam@amazon.com>
Signed-off-by: Paolo Bonzini