Re: [PATCH v3 0/6] KVM: LoongArch: selftests: Add timer test case

[Huacai Chen]

Hi, Bibo,

On Thu, Nov 20, 2025 at 2:58 PM Bibo Mao <maobibo@xxxxxxxxxxx> wrote:
>
> This patchset adds timer test case for LoongArch system, it is based
> on common arch_timer test case. And it includes one-shot and period mode
> timer interrupt test, software emulated timer function and time counter
> test.
I test this series on top of 6.18-rc6 with Loongson-3A5000, sometimes
it passes, sometimes I get:
[root@fedora kvm]# ./arch_timer
Random seed: 0x6b8b4567
Guest assert failed,  vcpu 2; stage; 0; iter: 1
==== Test Assertion Failure ====
  loongarch/arch_timer.c:79: irq_iter == 0
  pid=60138 tid=60142 errno=4 - Interrupted system call
     1  0x00000001200037cf: test_vcpu_run 于 arch_timer.c:70
     2  0x00007ffff2449f27: ?? ??:0
     3  0x00007ffff24c0633: ?? ??:0
  irq_iter = 0x1.
  Guest period timer interrupt was not triggered within the specified
  interval, try to increase the error margin by [-e] option.

Is this as expected, or something is wrong?

Hucai

> ---
> v2 ... v3:
>   1. Adjust order about patch 2 and patch 3
>   2. Add test case with alphabetical order
>   3. Merge one-shot and period timer interrupt test case into one
>   4. Only add LoongArch specific modification with common file
>      Makefile.kvm
>
> v1 ... v2:
>   1. Restore PC and PRMD after exception handler
>   2. Split patch 4 into two small patches with period timer test and
>      time counter test
>   3. With time counter test, set time count with 0 when create VM. And
>      verify time count starts from 0 in guest code
> ---
> Bibo Mao (6):
>   KVM: LoongArch: selftests: Add system registers save and restore on
>     exception
>   KVM: LoongArch: selftests: Add basic interfaces
>   KVM: LoongArch: selftests: Add exception handler register interface
>   KVM: LoongArch: selftests: Add timer interrupt test case
>   KVM: LoongArch: selftests: Add SW emulated timer test
>   KVM: LoongArch: selftests: Add time counter test
>
>  tools/testing/selftests/kvm/Makefile.kvm      |   1 +
>  .../kvm/include/loongarch/arch_timer.h        |  84 ++++++++
>  .../kvm/include/loongarch/processor.h         |  81 +++++++-
>  .../selftests/kvm/lib/loongarch/exception.S   |   6 +
>  .../selftests/kvm/lib/loongarch/processor.c   |  47 ++++-
>  .../selftests/kvm/loongarch/arch_timer.c      | 194 ++++++++++++++++++
>  6 files changed, 410 insertions(+), 3 deletions(-)
>  create mode 100644 tools/testing/selftests/kvm/include/loongarch/arch_timer.h
>  create mode 100644 tools/testing/selftests/kvm/loongarch/arch_timer.c
>
>
> base-commit: 23cb64fb76257309e396ea4cec8396d4a1dbae68
> --
> 2.39.3
>