linux.git/tools/testing/selftests/kvm/lib/test_util.c, branch for-next

KVM: selftests: Define _GNU_SOURCE for all selftests code

2024-04-29T19:49:10+00:00

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 
Acked-by: Claudio Imbrenda 
Acked-by: Oliver Upton 
Acked-by: Anup Patel 
Reviewed-by: Muhammad Usama Anjum 
Link: https://lore.kernel.org/r/20240423190308.2883084-1-seanjc@google.com
Signed-off-by: Sean Christopherson

KVM: selftests: Generalize check_clocksource() from kvm_clock_test

2024-02-01T16:58:13+00:00

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 
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

KVM: selftests: Assert that vasprintf() is successful

2023-09-20T16:26:31+00:00

Assert that vasprintf() succeeds as the "returned" string is undefined
on failure.  Checking the result also eliminates the only warning with
default options in KVM selftests, i.e. is the only thing getting in the
way of compile with -Werror.

  lib/test_util.c: In function ‘strdup_printf’:
  lib/test_util.c:390:9: error: ignoring return value of ‘vasprintf’
  declared with attribute ‘warn_unused_result’ [-Werror=unused-result]
  390 |         vasprintf(&str, fmt, ap);
      |         ^~~~~~~~~~~~~~~~~~~~~~~~

Don't bother capturing the return value, allegedly vasprintf() can only
fail due to a memory allocation failure.

Fixes: dfaf20af7649 ("KVM: arm64: selftests: Replace str_with_index with strdup_printf")
Cc: Andrew Jones 
Cc: Haibo Xu 
Cc: Anup Patel 
Signed-off-by: Sean Christopherson 
Reviewed-by: Andrew Jones 
Tested-by: Andrew Jones 
Message-Id: <20230914010636.1391735-1-seanjc@google.com>
Signed-off-by: Paolo Bonzini

KVM: arm64: selftests: Replace str_with_index with strdup_printf

2023-08-08T16:11:57+00:00

The original author of aarch64/get-reg-list.c (me) was wearing
tunnel vision goggles when implementing str_with_index(). There's
no reason to have such a special case string function. Instead,
take inspiration from glib and implement strdup_printf. The
implementation builds on vasprintf() which requires _GNU_SOURCE,
but we require _GNU_SOURCE in most files already.

Signed-off-by: Andrew Jones 
Signed-off-by: Haibo Xu 
Signed-off-by: Anup Patel

selftests: KVM: skip hugetlb tests if huge pages are not available

2023-03-14T14:20:06+00:00

Right now, if KVM memory stress tests are run with hugetlb sources but hugetlb is
not available (either in the kernel or because /proc/sys/vm/nr_hugepages is 0)
the test will fail with a memory allocation error.

This makes it impossible to add tests that default to hugetlb-backed memory,
because on a machine with a default configuration they will fail.  Therefore,
check HugePages_Total as well and, if zero, direct the user to enable hugepages
in procfs.  Furthermore, return KSFT_SKIP whenever hugetlb is not available.

Signed-off-by: Paolo Bonzini

KVM: selftests: implement random number generator for guest code

2022-11-16T18:09:19+00:00

Implement random number generator for guest code to randomize parts
of the test, making it less predictable and a more accurate reflection
of reality.

The random number generator chosen is the Park-Miller Linear
Congruential Generator, a fancy name for a basic and well-understood
random number generator entirely sufficient for this purpose.

Signed-off-by: Colton Lewis 
Reviewed-by: Sean Christopherson 
Reviewed-by: David Matlack 
Link: https://lore.kernel.org/r/20221107182208.479157-2-coltonlewis@google.com
Signed-off-by: Sean Christopherson

KVM: selftests: Add atoi_paranoid() to catch errors missed by atoi()

2022-11-16T18:03:24+00:00

atoi() doesn't detect errors. There is no way to know that a 0 return
is correct conversion or due to an error.

Introduce atoi_paranoid() to detect errors and provide correct
conversion. Replace all atoi() calls with atoi_paranoid().

Signed-off-by: Vipin Sharma 
Suggested-by: David Matlack 
Suggested-by: Sean Christopherson 
Reviewed-by: Sean Christopherson 
Link: https://lore.kernel.org/r/20221103191719.1559407-4-vipinsh@google.com
Signed-off-by: Sean Christopherson

KVM: selftests: Assert mmap HVA is aligned when using HugeTLB

2021-11-16T12:43:25+00:00

Manually padding and aligning the mmap region is only needed when using
THP. When using HugeTLB, mmap will always return an address aligned to
the HugeTLB page size. Add a comment to clarify this and assert the mmap
behavior for HugeTLB.

[Removed requirement that HugeTLB mmaps must be padded per Yanan's
 feedback and added assertion that mmap returns aligned addresses
 when using HugeTLB.]

Cc: Ben Gardon 
Cc: Yanan Wang 
Cc: Andrew Jones 
Cc: Peter Xu 
Cc: Aaron Lewis 
Signed-off-by: Sean Christopherson 
Signed-off-by: David Matlack 
Message-Id: <20211111000310.1435032-4-dmatlack@google.com>
Signed-off-by: Paolo Bonzini

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

2021-09-27T20:58:23+00:00

Pull kvm fixes from Paolo Bonzini:
 "A bit late... I got sidetracked by back-from-vacation routines and
  conferences. But most of these patches are already a few weeks old and
  things look more calm on the mailing list than what this pull request
  would suggest.

  x86:

   - missing TLB flush

   - nested virtualization fixes for SMM (secure boot on nested
     hypervisor) and other nested SVM fixes

   - syscall fuzzing fixes

   - live migration fix for AMD SEV

   - mirror VMs now work for SEV-ES too

   - fixes for reset

   - possible out-of-bounds access in IOAPIC emulation

   - fix enlightened VMCS on Windows 2022

  ARM:

   - Add missing FORCE target when building the EL2 object

   - Fix a PMU probe regression on some platforms

  Generic:

   - KCSAN fixes

  selftests:

   - random fixes, mostly for clang compilation"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (43 commits)
  selftests: KVM: Explicitly use movq to read xmm registers
  selftests: KVM: Call ucall_init when setting up in rseq_test
  KVM: Remove tlbs_dirty
  KVM: X86: Synchronize the shadow pagetable before link it
  KVM: X86: Fix missed remote tlb flush in rmap_write_protect()
  KVM: x86: nSVM: don't copy virt_ext from vmcb12
  KVM: x86: nSVM: test eax for 4K alignment for GP errata workaround
  KVM: x86: selftests: test simultaneous uses of V_IRQ from L1 and L0
  KVM: x86: nSVM: restore int_vector in svm_clear_vintr
  kvm: x86: Add AMD PMU MSRs to msrs_to_save_all[]
  KVM: x86: nVMX: re-evaluate emulation_required on nested VM exit
  KVM: x86: nVMX: don't fail nested VM entry on invalid guest state if !from_vmentry
  KVM: x86: VMX: synthesize invalid VM exit when emulating invalid guest state
  KVM: x86: nSVM: refactor svm_leave_smm and smm_enter_smm
  KVM: x86: SVM: call KVM_REQ_GET_NESTED_STATE_PAGES on exit from SMM mode
  KVM: x86: reset pdptrs_from_userspace when exiting smm
  KVM: x86: nSVM: restore the L1 host state prior to resuming nested guest on SMM exit
  KVM: nVMX: Filter out all unsupported controls when eVMCS was activated
  KVM: KVM: Use cpumask_available() to check for NULL cpumask when kicking vCPUs
  KVM: Clean up benign vcpu->cpu data races when kicking vCPUs
  ...

KVM: selftests: Refactor help message for -s backing_src

2021-09-22T14:33:14+00:00

All selftests that support the backing_src option were printing their
own description of the flag and then calling backing_src_help() to dump
the list of available backing sources. Consolidate the flag printing in
backing_src_help() to align indentation, reduce duplicated strings, and
improve consistency across tests.

Note: Passing "-s" to backing_src_help is unnecessary since every test
uses the same flag. However I decided to keep it for code readability
at the call sites.

While here this opportunistically fixes the incorrectly interleaved
printing -x help message and list of backing source types in
dirty_log_perf_test.

Fixes: 609e6202ea5f ("KVM: selftests: Support multiple slots in dirty_log_perf_test")
Reviewed-by: Ben Gardon 
Reviewed-by: Andrew Jones 
Signed-off-by: David Matlack 
Message-Id: <20210917173657.44011-3-dmatlack@google.com>
Signed-off-by: Paolo Bonzini