Explicitly clobber the guest IDT in the "delete memslot" test, which
expects the deleted memslot to result in either a KVM emulation error, or
a triple fault shutdown. A future change to the core selftests library
will configuring the guest IDT and exception handlers by default, i.e.
will install a guest #PF handler and put the guest into an infinite #NPF
loop (the guest hits a !PRESENT SPTE when trying to vector a #PF, and KVM
reinjects the #PF without fixing the #NPF, because there is no memslot).
Note, it's not clear whether or not KVM's behavior is reasonable in this
case, e.g. arguably KVM should try (and fail) to emulate in response to
the #NPF. But barring a goofy/broken userspace, this scenario will likely
never happen in practice. Punt the KVM investigation to the future.
Link: https://lore.kernel.org/r/20240314232637.2538648-8-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Rework platform_info_test to actually handle and verify the expected #GP
on RDMSR when the associated KVM capability is disabled. Currently, the
test _deliberately_ doesn't handle the #GP, and instead lets it escalated
to a triple fault shutdown.
In addition to verifying that KVM generates the correct fault, handling
the #GP will be necessary (without even more shenanigans) when a future
change to the core KVM selftests library configures the IDT and exception
handlers by default (the test subtly relies on the IDT limit being '0').
Link: https://lore.kernel.org/r/20240314232637.2538648-7-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
As a first step toward gracefully handling the expected #GP on RDMSR in
platform_info_test, move the test's assert on the non-faulting RDMSR
result into the guest itself. This will allow using a unified flow for
the host userspace side of things.
Link: https://lore.kernel.org/r/20240314232637.2538648-6-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Fix an off-by-one bug in the initialization of the GDT limit, which as
defined in the SDM is inclusive, not exclusive.
Note, vcpu_init_descriptor_tables() gets the limit correct, it's only
vcpu_setup() that is broken, i.e. only tests that _don't_ invoke
vcpu_init_descriptor_tables() can have problems. And the fact that KVM
effectively initializes the GDT twice will be cleaned up in the near
future.
Signed-off-by: Ackerley Tng <ackerleytng@google.com>
[sean: rewrite changelog]
Link: https://lore.kernel.org/r/20240314232637.2538648-5-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>
SBI PMU test comprises of multiple tests and user may want to run
only a subset depending on the platform. The most common case would
be to run all to validate all the tests. However, some platform may
not support all events or all ISA extensions.
The commandline option allows user to disable any set of tests if
they want to.
Suggested-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Link: https://lore.kernel.org/r/20240420151741.962500-25-atishp@rivosinc.com
Signed-off-by: Anup Patel <anup@brainfault.org>
Add a test for verifying overflow interrupt. Currently, it relies on
overflow support on cycle/instret events. This test works for cycle/
instret events which support sampling via hpmcounters on the platform.
There are no ISA extensions to detect if a platform supports that. Thus,
this test will fail on platform with virtualization but doesn't
support overflow on these two events.
Reviewed-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Link: https://lore.kernel.org/r/20240420151741.962500-24-atishp@rivosinc.com
Signed-off-by: Anup Patel <anup@brainfault.org>
If this feature is not supported or is disabled by IA32_MISC_ENABLE on
the host, executing MONITOR or MWAIT instruction from the guest doesn't
cause monitor/mwait VM exits, but a #UD.
So, we need to skip this test if CPUID.01H:ECX[3] is cleared.
Signed-off-by: Zide Chen <zide.chen@intel.com>
Link: https://lore.kernel.org/r/20240411210237.34646-1-zide.chen@intel.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
xen_shinfo_test is observed to be flaky failing sporadically with
"VM time too old". With min_ts/max_ts debug print added:
Wall clock (v 3269818) 1704906491.986255664
Time info 1: v 1282712 tsc 33530585736 time 14014430025 mul 3587552223 shift 4294967295 flags 1
Time info 2: v 1282712 tsc 33530585736 time 14014430025 mul 3587552223 shift 4294967295 flags 1
min_ts: 1704906491.986312153
max_ts: 1704906506.001006963
==== Test Assertion Failure ====
x86_64/xen_shinfo_test.c:1003: cmp_timespec(&min_ts, &vm_ts) <= 0
pid=32724 tid=32724 errno=4 - Interrupted system call
1 0x00000000004030ad: main at xen_shinfo_test.c:1003
2 0x00007fca6b23feaf: ?? ??:0
3 0x00007fca6b23ff5f: ?? ??:0
4 0x0000000000405e04: _start at ??:?
VM time too old
The test compares wall clock data from shinfo (which is the output of
kvm_get_wall_clock_epoch()) against clock_gettime(CLOCK_REALTIME) in the
host system before the VM is created. In the example above, it compares
shinfo: 1704906491.986255664 vs min_ts: 1704906491.986312153
and fails as the later is greater than the former. While this sounds like
a sane test, it doesn't pass reality check: kvm_get_wall_clock_epoch()
calculates guest's epoch (realtime when the guest was created) by
subtracting kvmclock from the current realtime and the calculation happens
when shinfo is setup. The problem is that kvmclock is a raw clock and
realtime clock is affected by NTP. This means that if realtime ticks with a
slightly reduced frequency, "guest's epoch" calculated by
kvm_get_wall_clock_epoch() will actually tick backwards! This is not a big
issue from guest's perspective as the guest can't really observe this but
this epoch can't be compared with a fixed clock_gettime() on the host.
Replace the check with comparing wall clock data from shinfo to
KVM_GET_CLOCK. The later gives both realtime and kvmclock so guest's epoch
can be calculated by subtraction. Note, CLOCK_REALTIME is susceptible to
leap seconds jumps but there's no better alternative in KVM at this
moment. Leave a comment and accept 1s delta.
Reported-by: Jan Richter <jarichte@redhat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20240206151950.31174-1-vkuznets@redhat.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Now that all the infrastructure is in place, add a test to stress KVM's
LPI injection. Keep a 1:1 mapping of device IDs to signalling threads,
allowing the user to scale up/down the sender side of an LPI. Make use
of the new VM stats for the translation cache to estimate the
translation hit rate.
Since the primary focus of the test is on performance, you'll notice
that the guest code is not pedantic about the LPIs it receives. Counting
the number of LPIs would require synchronization between the device and
vCPU threads to avoid coalescing and would get in the way of performance
numbers.
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240422200158.2606761-20-oliver.upton@linux.dev
Signed-off-by: Marc Zyngier <maz@kernel.org>
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>
Assert that accesses to a non-existent vgic-v2 CPU interface
consistently fail across the various KVM device attr ioctls. This also
serves as a regression test for a bug wherein KVM hits a NULL
dereference when the CPUID specified in the ioctl is invalid.
Note that there is no need to print the observed errno, as TEST_ASSERT()
will take care of it.
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20240424173959.3776798-3-oliver.upton@linux.dev
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
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>
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>
With multiple reader threads POLLing a single UFFD, the demand paging test
suffers from the thundering herd problem: performance degrades as the
number of reader threads is increased. Solve this issue [1] by switching
the the polling mechanism to EPOLL + EPOLLEXCLUSIVE.
Also, change the error-handling convention of uffd_handler_thread_fn.
Instead of just printing errors and returning early from the polling
loop, check for them via TEST_ASSERT(). "return NULL" is reserved for a
successful exit from uffd_handler_thread_fn, i.e. one triggered by a
write to the exit pipe.
Performance samples generated by the command in [2] are given below.
Num Reader Threads, Paging Rate (POLL), Paging Rate (EPOLL)
1 249k 185k
2 201k 235k
4 186k 155k
16 150k 217k
32 89k 198k
[1] Single-vCPU performance does suffer somewhat.
[2] ./demand_paging_test -u MINOR -s shmem -v 4 -o -r <num readers>
Signed-off-by: Anish Moorthy <amoorthy@google.com>
Acked-by: James Houghton <jthoughton@google.com>
Link: https://lore.kernel.org/r/20240215235405.368539-13-amoorthy@google.com
Signed-off-by: Sean Christopherson <seanjc@google.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>
Using the overall demand paging rate to measure performance can be
slightly misleading when vCPU accesses are not overlapped. Adding more
vCPUs will (usually) increase the overall demand paging rate even
if performance remains constant or even degrades on a per-vcpu basis. As
such, it makes sense to report both the total and per-vcpu paging rates.
Signed-off-by: Anish Moorthy <amoorthy@google.com>
Link: https://lore.kernel.org/r/20240215235405.368539-11-amoorthy@google.com
[sean: fix formatting]
Signed-off-by: Sean Christopherson <seanjc@google.com>
max_guest_memory_test uses ucalls to sync with the host, but
it also resets the guest RIP back to its initial value in between
tests stages.
This makes the guest never reach the code which frees the ucall struct
and since a fixed pool of 512 ucall structs is used, the test starts
to fail when more that 256 vCPUs are used.
Fix that by replacing the manual register reset with a loop in
the guest code.
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Link: https://lore.kernel.org/r/20240315143507.102629-1-mlevitsk@redhat.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>
KVM/arm64 fixes for 6.9, part #1
- Ensure perf events programmed to count during guest execution
are actually enabled before entering the guest in the nVHE
configuration.
- Restore out-of-range handler for stage-2 translation faults.
- Several fixes to stage-2 TLB invalidations to avoid stale
translations, possibly including partial walk caches.
- Fix early handling of architectural VHE-only systems to ensure E2H is
appropriately set.
- Correct a format specifier warning in the arch_timer selftest.
- Make the KVM banner message correctly handle all of the possible
configurations.
