linux.git/tools/testing/selftests/kvm/lib/assert.c, branch v7.3-rc2

Merge tag 'kvm-x86-selftests2-7.3' of https://github.com/kvm-x86/linux into HEAD

2026-08-18T11:24:04+00:00

KVM selftests changes for 7.3, part 2

 - Fix several issues with seeding KVM's pRNG, and rework the pRNG APIs to that
   the pRNG can be sanely used in host code, not just guest code.

 - Add an IRQ test to validate virtual IRQ deliverty for IRQs wired up via
   KVM_IRQFD + KVM_SET_GSI_ROUTING, with optional support for triggering IRQs
   via writes to an assigned VFIO device.

 - Add syscall wrappers to assert success on a variety of pthreads and CPU
   affinity APIs.

 - Set vCPU pthread affinity as early as possible to reduce contention issues
   that were surfaced by PREEMPT_LAZY, which result in runtimes of over a
   minute on large hosts, versus the expected ~5 seconds.

 - Rework the PMU counters test to run each testcase using a single VM with
   many vCPUs for each sub-testcase, instead of using a unique VM for each
   sub-testcase.  This cuts the runtime by ~20x.

KVM: selftests: Add a blank line before logging assertion failures

2026-07-29T12:45:27+00:00

Add a blank line for visual separation, which is especially useful for
tests that use carriage returns for same-line printing, in case a
failure occurs before a blank line is ever logged by the test.

Suggested-by: Sean Christopherson 
Signed-off-by: Yosry Ahmed 
Link: https://patch.msgid.link/20260728174232.2423257-8-yosry@kernel.org
Signed-off-by: Sean Christopherson

KVM: selftests: Add kvm_gettid() wrapper and convert users

2026-07-07T18:24:44+00:00

Add a KVM wrapper for the gettid() syscall so that tests don't have to
open code the syscall() themselves.  Unfortunately, not all flavors of
libc that KVM selftests support provide gettid().  Convert all existing
users of the syscall to the new wrapper.

Note, per the gettid() manpage[1], "This call is always successful", i.e.
prefixing kvm_ to the syscall name is aligned with the goal of providing
syscall wrappers that guarantee success.

No functional changes intended.

Link: https://man7.org/linux/man-pages/man2/gettid.2.html [1]
Suggested-by: Sean Christopherson 
Signed-off-by: Josh Hilke 
[sean: massage changelog]
Link: https://patch.msgid.link/20260626213534.3866178-16-seanjc@google.com
Signed-off-by: Sean Christopherson

KVM: selftests: Guard execinfo.h inclusion for non-glibc builds

2026-05-13T17:38:02+00:00

The backtrace() function and execinfo.h are GNU extensions available
in glibc but not in non-glibc C libraries such as musl. Building KVM
selftests with musl-gcc fails with:

  lib/assert.c:9:10: fatal error: execinfo.h: No such file or directory

Fix this by guarding the inclusion of execinfo.h and the stack dumping
logic under #ifdef __GLIBC__. For non-glibc builds, provide a local
stub for test_dump_stack().

Suggested-by: Aqib Faruqui 
Suggested-by: Sean Christopherson 
Signed-off-by: Hisam Mehboob 
Link: https://patch.msgid.link/20260409153846.1502656-2-hisamshar@gmail.com
Signed-off-by: Sean Christopherson

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: Gracefully handle empty stack traces

2022-09-30T10:38:00+00:00

Bail out of test_dump_stack() if the stack trace is empty rather than
invoking addr2line with zero addresses. The problem with the latter is
that addr2line will block waiting for addresses to be passed in via
stdin, e.g. if running a selftest from an interactive terminal.

Opportunistically fix up the comment that mentions skipping 3 frames
since only 2 are skipped in the code.

Cc: Vipin Sharma 
Cc: Sean Christopherson 
Signed-off-by: David Matlack 
Message-Id: <20220922231724.3560211-1-dmatlack@google.com>
[Small tweak to keep backtrace() call close to if(). - Paolo]
Signed-off-by: Paolo Bonzini

KVM: selftests: Print the errno besides error-string in TEST_ASSERT

2021-04-20T08:18:52+00:00

Print the errno besides error-string in TEST_ASSERT in the format of
"errno=%d - %s" will explicitly indicate that the string is an error
information. Besides, the errno is easier to be used for debugging
than the error-string.

Suggested-by: Andrew Jones 
Signed-off-by: Yanan Wang 
Reviewed-by: Andrew Jones 
Message-Id: <20210330080856.14940-5-wangyanan55@huawei.com>
Signed-off-by: Paolo Bonzini

KVM: selftests: Use consistent message for test skipping

2020-03-16T16:59:05+00:00

Signed-off-by: Andrew Jones 
Signed-off-by: Paolo Bonzini

selftests: kvm: fix build with glibc >= 2.30

2019-11-13T14:48:00+00:00

Glibc-2.30 gained gettid() wrapper, selftests fail to compile:

lib/assert.c:58:14: error: static declaration of ‘gettid’ follows non-static declaration
   58 | static pid_t gettid(void)
      |              ^~~~~~
In file included from /usr/include/unistd.h:1170,
                 from include/test_util.h:18,
                 from lib/assert.c:10:
/usr/include/bits/unistd_ext.h:34:16: note: previous declaration of ‘gettid’ was here
   34 | extern __pid_t gettid (void) __THROW;
      |                ^~~~~~

Signed-off-by: Vitaly Kuznetsov 
Signed-off-by: Paolo Bonzini

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 482

2019-06-19T15:09:52+00:00

Based on 1 normalized pattern(s):

  this work is licensed under the terms of the gnu gpl version 2

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 48 file(s).

Signed-off-by: Thomas Gleixner 
Reviewed-by: Allison Randal 
Reviewed-by: Enrico Weigelt 
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081204.624030236@linutronix.de
Signed-off-by: Greg Kroah-Hartman