Extend vmx_dirty_log_test to include accesses made by L2 when EPT is
disabled.
This commit adds explicit coverage of a bug caught by syzkaller, where
the TDP MMU would clear D-bits instead of write-protecting SPTEs being
used to map an L2, which only happens when L1 does not enable EPT,
causing writes made by L2 to not be reflected in the dirty log when PML
is enabled:
$ ./vmx_dirty_log_test
Nested EPT: disabled
==== Test Assertion Failure ====
x86_64/vmx_dirty_log_test.c:151: test_bit(0, bmap)
pid=72052 tid=72052 errno=4 - Interrupted system call
(stack trace empty)
Page 0 incorrectly reported clean
Opportunistically replace the volatile casts with {READ,WRITE}_ONCE().
Link: https://lore.kernel.org/kvm/000000000000c6526f06137f18cc@google.com/
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20240315230541.1635322-5-dmatlack@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Add a guest assert in the PMU counters test to verify that KVM stuffs
the vCPU's post-RESET value to globally enable all general purpose
counters. Per Intel's SDM,
IA32_PERF_GLOBAL_CTRL: Sets bits n-1:0 and clears the upper bits.
and
Where "n" is the number of general-purpose counters available in
the processor.
For the edge case where there are zero GP counters, follow the spirit
of the architecture, not the SDM's literal wording, which doesn't account
for this possibility and would require the CPU to set _all_ bits in
PERF_GLOBAL_CTRL.
Reviewed-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Tested-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Link: https://lore.kernel.org/r/20240309013641.1413400-3-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Fix a bug in KVM_SET_CPUID{2,} where KVM looks at the wrong CPUID entries (old
vs. new) and ultimately neglects to clear PV_UNHALT from vCPUs with HLT-exiting
disabled.
KVM Xen and pfncache changes for 6.9:
- Rip out the half-baked support for using gfn_to_pfn caches to manage pages
that are "mapped" into guests via physical addresses.
- Add support for using gfn_to_pfn caches with only a host virtual address,
i.e. to bypass the "gfn" stage of the cache. The primary use case is
overlay pages, where the guest may change the gfn used to reference the
overlay page, but the backing hva+pfn remains the same.
- Add an ioctl() to allow mapping Xen's shared_info page using an hva instead
of a gpa, so that userspace doesn't need to reconfigure and invalidate the
cache/mapping if the guest changes the gpa (but userspace keeps the resolved
hva the same).
- When possible, use a single host TSC value when computing the deadline for
Xen timers in order to improve the accuracy of the timer emulation.
- Inject pending upcall events when the vCPU software-enables its APIC to fix
a bug where an upcall can be lost (and to follow Xen's behavior).
- Fall back to the slow path instead of warning if "fast" IRQ delivery of Xen
events fails, e.g. if the guest has aliased xAPIC IDs.
- Extend gfn_to_pfn_cache's mutex to cover (de)activation (in addition to
refresh), and drop a now-redundant acquisition of xen_lock (that was
protecting the shared_info cache) to fix a deadlock due to recursively
acquiring xen_lock.
KVM x86 PMU changes for 6.9:
- Fix several bugs where KVM speciously prevents the guest from utilizing
fixed counters and architectural event encodings based on whether or not
guest CPUID reports support for the _architectural_ encoding.
- Fix a variety of bugs in KVM's emulation of RDPMC, e.g. for "fast" reads,
priority of VMX interception vs #GP, PMC types in architectural PMUs, etc.
- Add a selftest to verify KVM correctly emulates RDMPC, counter availability,
and a variety of other PMC-related behaviors that depend on guest CPUID,
i.e. are difficult to validate via KVM-Unit-Tests.
- Zero out PMU metadata on AMD if the virtual PMU is disabled to avoid wasting
cycles, e.g. when checking if a PMC event needs to be synthesized when
skipping an instruction.
- Optimize triggering of emulated events, e.g. for "count instructions" events
when skipping an instruction, which yields a ~10% performance improvement in
VM-Exit microbenchmarks when a vPMU is exposed to the guest.
- Tighten the check for "PMI in guest" to reduce false positives if an NMI
arrives in the host while KVM is handling an IRQ VM-Exit.
KVM selftests changes for 6.9:
- Add macros to reduce the amount of boilerplate code needed to write "simple"
selftests, and to utilize selftest TAP infrastructure, which is especially
beneficial for KVM selftests with multiple testcases.
- Add basic smoke tests for SEV and SEV-ES, along with a pile of library
support for handling private/encrypted/protected memory.
- Fix benign bugs where tests neglect to close() guest_memfd files.
KVM_FEATURE_PV_UNHALT is expected to get cleared from KVM PV feature CPUID
data when KVM_X86_DISABLE_EXITS_HLT is enabled. Add the corresponding test
to kvm_pv_test.
Note, the newly added code doesn't actually test KVM_FEATURE_PV_UNHALT and
KVM_X86_DISABLE_EXITS_HLT features.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20240228101837.93642-4-vkuznets@redhat.com
[sean: add and use vcpu_cpuid_has()]
Signed-off-by: Sean Christopherson <seanjc@google.com>
Explicitly close() guest_memfd files in various guest_memfd and
private_mem_conversions tests, there's no reason to keep the files open
until the test exits.
Fixes: 8a89efd434 ("KVM: selftests: Add basic selftest for guest_memfd()")
Fixes: 43f623f350 ("KVM: selftests: Add x86-only selftest for private memory conversions")
Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com>
Link: https://lore.kernel.org/r/20240227015716.27284-1-dongli.zhang@oracle.com
[sean: massage changelog]
Signed-off-by: Sean Christopherson <seanjc@google.com>
Extend sev_smoke_test to also run a minimal SEV-ES smoke test so that it's
possible to test KVM's unique VMRUN=>#VMEXIT path for SEV-ES guests
without needing a full blown SEV-ES capable VM, which requires a rather
absurd amount of properly configured collateral.
Punt on proper GHCB and ucall support, and instead use the GHCB MSR
protocol to signal test completion. The most important thing at this
point is to have _any_ kind of testing of KVM's __svm_sev_es_vcpu_run().
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Michael Roth <michael.roth@amd.com>
Cc: Peter Gonda <pgonda@google.com>
Cc: Carlos Bilbao <carlos.bilbao@amd.com>
Tested-by: Carlos Bilbao <carlos.bilbao@amd.com>
Link: https://lore.kernel.org/r/20240223004258.3104051-12-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
The sync_regs test currently does not have any output (unless one
of the TEST_ASSERT statement fails), so it's hard to say for a user
whether a certain new sub-test has been included in the binary or
not. Let's make this a little bit more user-friendly and include
some TAP output via the kselftest_harness.h / kvm_test_harness.h
interface.
To be able to use the interface, we have to break up the huge main()
function here in more fine grained parts - then we can use the new
KVM_ONE_VCPU_TEST() macro to define the individual tests. Since these
are run with a separate VM now, we have also to make sure to create
the expected state at the beginning of each test, so some parts grow
a little bit - which should be OK considering that the individual
tests are more self-contained now.
Suggested-by: David Matlack <dmatlack@google.com>
Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Link: https://lore.kernel.org/r/20240208204844.119326-6-thuth@redhat.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Using the HVA of the shared_info page is more efficient, so if the
capability (KVM_XEN_HVM_CONFIG_SHARED_INFO_HVA) is present use that method
to do the mapping.
NOTE: Have the juggle_shinfo_state() thread map and unmap using both
GFN and HVA, to make sure the older mechanism is not broken.
Signed-off-by: Paul Durrant <pdurrant@amazon.com>
Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
Link: https://lore.kernel.org/r/20240215152916.1158-15-paul@xen.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Although the fixed counter 3 and its exclusive pseudo slots event are
not supported by KVM yet, the architectural slots event is supported by
KVM and can be programmed on any GP counter. Thus add validation for this
architectural slots event.
Top-down slots event "counts the total number of available slots for an
unhalted logical processor, and increments by machine-width of the
narrowest pipeline as employed by the Top-down Microarchitecture
Analysis method."
As for the slot, it's an abstract concept which indicates how many
uops (decoded from instructions) can be processed simultaneously
(per cycle) on HW. In Top-down Microarchitecture Analysis (TMA) method,
the processor is divided into two parts, frond-end and back-end. Assume
there is a processor with classic 5-stage pipeline, fetch, decode,
execute, memory access and register writeback. The former 2 stages
(fetch/decode) are classified to frond-end and the latter 3 stages are
classified to back-end.
In modern Intel processors, a complicated instruction would be decoded
into several uops (micro-operations) and so these uops can be processed
simultaneously and then improve the performance. Thus, assume a
processor can decode and dispatch 4 uops in front-end and execute 4 uops
in back-end simultaneously (per-cycle), so the machine-width of this
processor is 4 and this processor has 4 topdown slots per-cycle.
If a slot is spare and can be used to process a new upcoming uop, then
the slot is available, but if a uop occupies a slot for several cycles
and can't be retired (maybe blocked by memory access), then this slot is
stall and unavailable.
Considering the testing instruction sequence can't be macro-fused on x86
platforms, the measured slots count should not be less than
NUM_INSNS_RETIRED. Thus assert the slots count against NUM_INSNS_RETIRED.
pmu_counters_test passed with this patch on Intel Sapphire Rapids.
About the more information about TMA method, please refer the below link.
https://www.intel.com/content/www/us/en/docs/vtune-profiler/cookbook/2023-0/top-down-microarchitecture-analysis-method.html
Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Link: https://lore.kernel.org/r/20240218043003.2424683-1-dapeng1.mi@linux.intel.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Drop dirty_log_page_splitting_test's assertion that the number of 4KiB
pages remains the same across dirty logging being enabled and disabled, as
the test doesn't guarantee that mappings outside of the memslots being
dirty logged are stable, e.g. KVM's mappings for code and pages in
memslot0 can be zapped by things like NUMA balancing.
To preserve the spirit of the check, assert that (a) the number of 4KiB
pages after splitting is _at least_ the number of 4KiB pages across all
memslots under test, and (b) the number of hugepages before splitting adds
up to the number of pages across all memslots under test. (b) is a little
tenuous as it relies on memslot0 being incompatible with transparent
hugepages, but that holds true for now as selftests explicitly madvise()
MADV_NOHUGEPAGE for memslot0 (__vm_create() unconditionally specifies the
backing type as VM_MEM_SRC_ANONYMOUS).
Reported-by: Yi Lai <yi1.lai@intel.com>
Reported-by: Tao Su <tao1.su@linux.intel.com>
Reviewed-by: Tao Su <tao1.su@linux.intel.com>
Link: https://lore.kernel.org/r/20240131222728.4100079-1-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
KVM sets up Hyper-V TSC page clocksource for its guests when system
clocksource is 'based on TSC' (see gtod_is_based_on_tsc()), running
hyperv_clock with any other clocksource leads to imminent failure.
Add the missing requirement to make the test skip gracefully.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20240109141121.1619463-5-vkuznets@redhat.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
KVM's 'gtod_is_based_on_tsc()' recognizes two clocksources: 'tsc' and
'hyperv_clocksource_tsc_page' and enables kvmclock in 'masterclock'
mode when either is in use. Transform 'sys_clocksource_is_tsc()' into
'sys_clocksource_is_based_on_tsc()' to support the later. This affects
two tests: kvm_clock_test and vmx_nested_tsc_scaling_test, both seem
to work well when system clocksource is 'hyperv_clocksource_tsc_page'.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20240109141121.1619463-4-vkuznets@redhat.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Several existing x86 selftests need to check that the underlying system
clocksource is TSC or based on TSC but every test implements its own
check. As a first step towards unification, extract check_clocksource()
from kvm_clock_test and split it into two functions: arch-neutral
'sys_get_cur_clocksource()' and x86-specific 'sys_clocksource_is_tsc()'.
Fix a couple of pre-existing issues in kvm_clock_test: memory leakage in
check_clocksource() and using TEST_ASSERT() instead of TEST_REQUIRE().
The change also makes the test fail when system clocksource can't be read
from sysfs.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20240109141121.1619463-2-vkuznets@redhat.com
[sean: eliminate if-elif pattern just to set a bool true]
Signed-off-by: Sean Christopherson <seanjc@google.com>
Extend the read/write PMU counters subtest to verify that RDPMC also reads
back the written value. Opportunsitically verify that attempting to use
the "fast" mode of RDPMC fails, as the "fast" flag is only supported by
non-architectural PMUs, which KVM doesn't virtualize.
Tested-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Link: https://lore.kernel.org/r/20240109230250.424295-30-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Expand the PMU counters test to verify that LLC references and misses have
non-zero counts when the code being executed while the LLC event(s) is
active is evicted via CFLUSH{,OPT}. Note, CLFLUSH{,OPT} requires a fence
of some kind to ensure the cache lines are flushed before execution
continues. Use MFENCE for simplicity (performance is not a concern).
Suggested-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Tested-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Link: https://lore.kernel.org/r/20240109230250.424295-22-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Add test cases to verify that Intel's Architectural PMU events work as
expected when they are available according to guest CPUID. Iterate over a
range of sane PMU versions, with and without full-width writes enabled,
and over interesting combinations of lengths/masks for the bit vector that
enumerates unavailable events.
Test up to vPMU version 5, i.e. the current architectural max. KVM only
officially supports up to version 2, but the behavior of the counters is
backwards compatible, i.e. KVM shouldn't do something completely different
for a higher, architecturally-defined vPMU version. Verify KVM behavior
against the effective vPMU version, e.g. advertising vPMU 5 when KVM only
supports vPMU 2 shouldn't magically unlock vPMU 5 features.
According to Intel SDM, the number of architectural events is reported
through CPUID.0AH:EAX[31:24] and the architectural event x is supported
if EBX[x]=0 && EAX[31:24]>x.
Handcode the entirety of the measured section so that the test can
precisely assert on the number of instructions and branches retired.
Co-developed-by: Like Xu <likexu@tencent.com>
Signed-off-by: Like Xu <likexu@tencent.com>
Signed-off-by: Jinrong Liang <cloudliang@tencent.com>
Co-developed-by: Sean Christopherson <seanjc@google.com>
Tested-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Link: https://lore.kernel.org/r/20240109230250.424295-17-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
When X86_FEATURE_INVTSC is missing, guest_test_msrs_access() was supposed
to skip testing dependent Hyper-V invariant TSC feature. Unfortunately,
'continue' does not lead to that as stage is not incremented. Moreover,
'vm' allocated with vm_create_with_one_vcpu() is not freed and the test
runs out of available file descriptors very quickly.
Fixes: bd827bd775 ("KVM: selftests: Test Hyper-V invariant TSC control")
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20240129085847.2674082-1-vkuznets@redhat.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Delete the AMX's tests "stage" counter, as the counter is no longer used,
which makes clang unhappy:
x86_64/amx_test.c:224:6: error: variable 'stage' set but not used
int stage, ret;
^
1 error generated.
Note, "stage" was never really used, it just happened to be dumped out by
a (failed) assertion on run->exit_reason, i.e. the AMX test has no concept
of stages, the code was likely copy+pasted from a different test.
Fixes: c96f57b080 ("KVM: selftests: Make vCPU exit reason test assertion common")
Reviewed-by: Jim Mattson <jmattson@google.com>
Link: https://lore.kernel.org/r/20240109220302.399296-1-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Rework the NX hugepage test's skip message regarding the magic token to
provide all of the necessary magic, and to very explicitly recommended
using the wrapper shell script.
Opportunistically remove an overzealous newline; splitting the
recommendation message across two lines of ~45 characters makes it much
harder to read than running out a single line to 98 characters.
Link: https://lore.kernel.org/r/20231129224042.530798-1-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
KVM x86 Hyper-V changes for 6.8:
- Guard KVM-on-HyperV's range-based TLB flush hooks with an #ifdef on
CONFIG_HYPERV as a minor optimization, and to self-document the code.
- Add CONFIG_KVM_HYPERV to allow disabling KVM support for HyperV "emulation"
at build time.
The "vmxon_pa == vmcs12_pa == -1ull" test happens to work by accident: as
Enlightened VMCS is always supported, set_default_vmx_state() adds
'KVM_STATE_NESTED_EVMCS' to 'flags' and the following branch of
vmx_set_nested_state() is executed:
if ((kvm_state->flags & KVM_STATE_NESTED_EVMCS) &&
(!guest_can_use(vcpu, X86_FEATURE_VMX) ||
!vmx->nested.enlightened_vmcs_enabled))
return -EINVAL;
as 'enlightened_vmcs_enabled' is false. In fact, "vmxon_pa == vmcs12_pa ==
-1ull" is a valid state when not tainted by wrong flags so the test should
aim for this branch:
if (kvm_state->hdr.vmx.vmxon_pa == INVALID_GPA)
return 0;
Test all this properly:
- Without KVM_STATE_NESTED_EVMCS in the flags, the expected return value is
'0'.
- With KVM_STATE_NESTED_EVMCS flag (when supported) set, the expected
return value is '-EINVAL' prior to enabling eVMCS and '0' after.
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Tested-by: Jeremi Piotrowski <jpiotrowski@linux.microsoft.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20231205103630.1391318-11-vkuznets@redhat.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Swap the ordering of parameters to guest asserts related to {RD,WR}MSR
success/failure in the Hyper-V features test. As is, the output will
be mangled and broken due to passing an integer as a string and vice
versa.
Opportunistically fix a benign %u vs. %lu issue as well.
Link: https://lore.kernel.org/r/20231129224916.532431-4-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Convert %llx to %lx as appropriate in guest asserts. The guest printf
implementation treats them the same as KVM selftests are 64-bit only, but
strictly adhering to the correct format will allow annotating the
underlying helpers with __printf() without introducing new warnings in the
build.
Link: https://lore.kernel.org/r/20231129224916.532431-3-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Remove x86's mmio_warning_test, as it is unnecessarily complex (there's no
reason to fork, spawn threads, initialize srand(), etc..), unnecessarily
restrictive (triggering triple fault is not unique to Intel CPUs without
unrestricted guest), and provides no meaningful coverage beyond what
basic fuzzing can achieve (running a vCPU with garbage is fuzzing's bread
and butter).
That the test has *all* of the above flaws is not coincidental, as the
code was copy+pasted almost verbatim from the syzkaller reproducer that
originally found the KVM bug (which has long since been fixed).
Cc: Michal Luczaj <mhal@rbox.co>
Link: https://groups.google.com/g/syzkaller/c/lHfau8E3SOE
Link: https://lore.kernel.org/r/20230815220030.560372-1-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Pass MAGIC_TOKEN to __TEST_REQUIRE() when printing the help message about
needing to pass a magic value to manually run the NX hugepages test,
otherwise the help message will contain garbage.
In file included from x86_64/nx_huge_pages_test.c:15:
x86_64/nx_huge_pages_test.c: In function ‘main’:
include/test_util.h:40:32: error: format ‘%d’ expects a matching ‘int’ argument [-Werror=format=]
40 | ksft_exit_skip("- " fmt "\n", ##__VA_ARGS__); \
| ^~~~
x86_64/nx_huge_pages_test.c:259:9: note: in expansion of macro ‘__TEST_REQUIRE’
259 | __TEST_REQUIRE(token == MAGIC_TOKEN,
| ^~~~~~~~~~~~~~
Signed-off-by: angquan yu <angquan21@gmail.com>
Link: https://lore.kernel.org/r/20231128221105.63093-1-angquan21@gmail.com
[sean: rewrite shortlog+changelog]
Signed-off-by: Sean Christopherson <seanjc@google.com>
