Initialize the IDT and exception handlers for all non-barebones VMs and
vCPUs on x86. Forcing tests to manually configure the IDT just to save
8KiB of memory is a terrible tradeoff, and also leads to weird tests
(multiple tests have deliberately relied on shutdown to indicate success),
and hard-to-debug failures, e.g. instead of a precise unexpected exception
failure, tests see only shutdown.
Reviewed-by: Ackerley Tng <ackerleytng@google.com>
Link: https://lore.kernel.org/r/20240314232637.2538648-11-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Move the base types unique to KVM selftests out of kvm_util.h and into a
new header, kvm_util_types.h. This will allow kvm_util_arch.h, i.e. core
arch headers, to reference common types, e.g. vm_vaddr_t and vm_paddr_t.
No functional change intended.
Reviewed-by: Ackerley Tng <ackerleytng@google.com>
Link: https://lore.kernel.org/r/20240314232637.2538648-3-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Effectively revert the movement of code from kvm_util.h => kvm_util_base.h,
as the TL;DR of the justification for the move was to avoid #idefs and/or
circular dependencies between what ended up being ucall_common.h and what
was (and now again, is), kvm_util.h.
But avoiding #ifdef and circular includes is trivial: don't do that. The
cost of removing kvm_util_base.h is a few extra includes of ucall_common.h,
but that cost is practically nothing. On the other hand, having a "base"
version of a header that is really just the header itself is confusing,
and makes it weird/hard to choose names for headers that actually are
"base" headers, e.g. to hold core KVM selftests typedefs.
For all intents and purposes, this reverts commit
7d9a662ed9.
Reviewed-by: Ackerley Tng <ackerleytng@google.com>
Link: https://lore.kernel.org/r/20240314232637.2538648-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Override vcpu_arch_put_guest() to randomly force emulation on supported
accesses. Force emulation of LOCK CMPXCHG as well as a regular MOV to
stress KVM's emulation of atomic accesses, which has a unique path in
KVM's emulator.
Arbitrarily give all the decisions 50/50 odds; absent much, much more
sophisticated infrastructure for generating random numbers, it's highly
unlikely that doing more than a coin flip with affect selftests' ability
to find KVM bugs.
This is effectively a regression test for commit 910c57dfa4 ("KVM: x86:
Mark target gfn of emulated atomic instruction as dirty").
Link: https://lore.kernel.org/r/20240314185459.2439072-6-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Introduce a macro, vcpu_arch_put_guest(), for "putting" values to memory
from guest code in "interesting" situations, e.g. when writing memory that
is being dirty logged. Structure the macro so that arch code can provide
a custom implementation, e.g. x86 will use the macro to force emulation of
the access.
Use the helper in dirty_log_test, which is of particular interest (see
above), and in xen_shinfo_test, which isn't all that interesting, but
provides a second usage of the macro with a different size operand
(uint8_t versus uint64_t), i.e. to help verify that the macro works for
more than just 64-bit values.
Use "put" as the verb to align with the kernel's {get,put}_user()
terminology.
Link: https://lore.kernel.org/r/20240314185459.2439072-5-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Add a global snapshot of kvm_is_forced_emulation_enabled() and sync it to
all VMs by default so that core library code can force emulation, e.g. to
allow for easier testing of the intersections between emulation and other
features in KVM.
Link: https://lore.kernel.org/r/20240314185459.2439072-4-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Move memstress' random bool logic into common code to avoid reinventing
the wheel for basic yes/no decisions. Provide an outer wrapper to handle
the basic/common case of just wanting a 50/50 chance of something
happening.
Link: https://lore.kernel.org/r/20240314185459.2439072-3-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Add a global guest_random_state instance, i.e. a pseudo-RNG, so that an
RNG is available for *all* tests. This will allow randomizing behavior
in core library code, e.g. x86 will utilize the pRNG to conditionally
force emulation of writes from within common guest code.
To allow for deterministic runs, and to be compatible with existing tests,
allow tests to override the seed used to initialize the pRNG.
Note, the seed *must* be overwritten before a VM is created in order for
the seed to take effect, though it's perfectly fine for a test to
initialize multiple VMs with different seeds.
And as evidenced by memstress_guest_code(), it's also a-ok to instantiate
more RNGs using the global seed (or a modified version of it). The goal
of the global RNG is purely to ensure that _a_ source of random numbers is
available, it doesn't have to be the _only_ RNG.
Link: https://lore.kernel.org/r/20240314185459.2439072-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Define _GNU_SOURCE is the base CFLAGS instead of relying on selftests to
manually #define _GNU_SOURCE, which is repetitive and error prone. E.g.
kselftest_harness.h requires _GNU_SOURCE for asprintf(), but if a selftest
includes kvm_test_harness.h after stdio.h, the include guards result in
the effective version of stdio.h consumed by kvm_test_harness.h not
defining asprintf():
In file included from x86_64/fix_hypercall_test.c:12:
In file included from include/kvm_test_harness.h:11:
../kselftest_harness.h:1169:2: error: call to undeclared function
'asprintf'; ISO C99 and later do not support implicit function declarations
[-Wimplicit-function-declaration]
1169 | asprintf(&test_name, "%s%s%s.%s", f->name,
| ^
When including the rseq selftest's "library" code, #undef _GNU_SOURCE so
that rseq.c controls whether or not it wants to build with _GNU_SOURCE.
Reported-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Acked-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Acked-by: Oliver Upton <oliver.upton@linux.dev>
Acked-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Link: https://lore.kernel.org/r/20240423190308.2883084-1-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
It would appear that all of the selftests are using the same exact
layout for the GIC frames. Fold this back into the library
implementation to avoid defining magic values all over the selftests.
This is an extension of Colton's change, ripping out parameterization of
from the library internals in addition to the public interfaces.
Co-developed-by: Colton Lewis <coltonlewis@google.com>
Signed-off-by: Colton Lewis <coltonlewis@google.com>
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240422200158.2606761-15-oliver.upton@linux.dev
Signed-off-by: Marc Zyngier <maz@kernel.org>
There are a few subtle incongruencies between the GIC definitions used
by the kernel and selftests. Furthermore, the selftests header blends
implementation detail (e.g. default priority) with the architectural
definitions.
This is all rather annoying, since bulk imports of the kernel header
is not possible. Move selftests-specific definitions out of the
offending header and realign tests on the canonical definitions for
things like sysregs. Finally, haul in a fresh copy of the gicv3 header
to enable a forthcoming ITS selftest.
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240422200158.2606761-14-oliver.upton@linux.dev
Signed-off-by: Marc Zyngier <maz@kernel.org>
Allow the caller to set the initial state of the VM. Doing this
before sev_vm_launch() matters for SEV-ES, since that is the
place where the VMSA is updated and after which the guest state
becomes sealed.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <20240404121327.3107131-17-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This removes the concept of "subtypes", instead letting the tests use proper
VM types that were recently added. While the sev_init_vm() and sev_es_init_vm()
are still able to operate with the legacy KVM_SEV_INIT and KVM_SEV_ES_INIT
ioctls, this is limited to VMs that are created manually with
vm_create_barebones().
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <20240404121327.3107131-16-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
At the moment, demand_paging_test does not support profiling/testing
multiple vCPU threads concurrently faulting on a single uffd because
(a) "-u" (run test in userfaultfd mode) creates a uffd for each vCPU's
region, so that each uffd services a single vCPU thread.
(b) "-u -o" (userfaultfd mode + overlapped vCPU memory accesses)
simply doesn't work: the test tries to register the same memory
to multiple uffds, causing an error.
Add support for many vcpus per uffd by
(1) Keeping "-u" behavior unchanged.
(2) Making "-u -a" create a single uffd for all of guest memory.
(3) Making "-u -o" implicitly pass "-a", solving the problem in (b).
In cases (2) and (3) all vCPU threads fault on a single uffd.
With potentially multiple vCPUs per UFFD, it makes sense to allow
configuring the number of reader threads per UFFD as well: add the "-r"
flag to do so.
Signed-off-by: Anish Moorthy <amoorthy@google.com>
Acked-by: James Houghton <jthoughton@google.com>
Link: https://lore.kernel.org/r/20240215235405.368539-12-amoorthy@google.com
[sean: fix kernel style violations, use calloc() for arrays]
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 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>
Add a KVM selftests to validate the Sstc timer functionality.
The test was ported from arm64 arch timer test.
Signed-off-by: Haibo Xu <haibo1.xu@intel.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Anup Patel <anup@brainfault.org>
Move vcpu_has_ext to the processor.c and rename it to __vcpu_has_ext
so that other test cases can use it for vCPU extension check.
Signed-off-by: Haibo Xu <haibo1.xu@intel.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Anup Patel <anup@brainfault.org>
Add guest_get_vcpuid() helper to simplify accessing to per-cpu
private data. The sscratch CSR was used to store the vcpu id.
Signed-off-by: Haibo Xu <haibo1.xu@intel.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Anup Patel <anup@brainfault.org>
Add the infrastructure for guest exception handling in riscv selftests.
Customized handlers can be enabled by vm_install_exception_handler(vector)
or vm_install_interrupt_handler().
The code is inspired from that of x86/arm64.
Signed-off-by: Haibo Xu <haibo1.xu@intel.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Anup Patel <anup@brainfault.org>
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>
Most tests are currently not giving any proper output for the user
to see how much sub-tests have already been run, or whether new
sub-tests are part of a binary or not. So it would be good to
support TAP output in the KVM selftests. There is already a nice
framework for this in the kselftest_harness.h header which we can
use. But since we also need a vcpu in most KVM selftests, it also
makes sense to introduce our own wrapper around this which takes
care of creating a VM with one vcpu, so we don't have to repeat
this boilerplate in each and every test. Thus let's introduce
a KVM_ONE_VCPU_TEST() macro here which takes care of this.
Suggested-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/all/Y2v+B3xxYKJSM%2FfH@google.com/
Signed-off-by: Thomas Huth <thuth@redhat.com>
Link: https://lore.kernel.org/r/20240208204844.119326-5-thuth@redhat.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Extract the code to set a vCPU's entry point out of vm_arch_vcpu_add() and
into a new API, vcpu_arch_set_entry_point(). Providing a separate API
will allow creating a KVM selftests hardness that can handle tests that
use different entry points for sub-tests, whereas *requiring* the entry
point to be specified at vCPU creation makes it difficult to create a
generic harness, e.g. the boilerplate setup/teardown can't easily create
and destroy the VM and vCPUs.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Link: https://lore.kernel.org/r/20240208204844.119326-4-thuth@redhat.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Split the arch-neutral test code out of aarch64/arch_timer.c
and put them into a common arch_timer.c. This is a preparation
to share timer test codes in riscv.
Suggested-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Haibo Xu <haibo1.xu@intel.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Anup Patel <anup@brainfault.org>
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>
Add KVM_ASM_SAFE_FEP() to allow forcing emulation on an instruction that
might fault. Note, KVM skips RIP past the FEP prefix before injecting an
exception, i.e. the fixup needs to be on the instruction itself. Do not
check for FEP support, that is firmly the responsibility of whatever code
wants to use KVM_ASM_SAFE_FEP().
Sadly, chaining variadic arguments that contain commas doesn't work, thus
the unfortunate amount of copy+paste.
Tested-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Link: https://lore.kernel.org/r/20240109230250.424295-28-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
