Re: [PATCH 3/4 V8] selftest: KVM: Add open sev dev helper

[Marc Orr <marcorr@google.com>]

On Tue, Sep 14, 2021 at 9:47 AM Peter Gonda <pgonda@google.com> wrote:
>
> Refactors out open path support from open_kvm_dev_path_or_exit() and
> adds new helper for SEV device path.
>
> Signed-off-by: Peter Gonda <pgonda@google.com>
> Suggested-by: Sean Christopherson <seanjc@google.com>
> Cc: Marc Orr <marcorr@google.com>
> Cc: Paolo Bonzini <pbonzini@redhat.com>
> Cc: Sean Christopherson <seanjc@google.com>
> Cc: David Rientjes <rientjes@google.com>
> Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
> Cc: Brijesh Singh <brijesh.singh@amd.com>
> Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
> Cc: Wanpeng Li <wanpengli@tencent.com>
> Cc: Jim Mattson <jmattson@google.com>
> Cc: Joerg Roedel <joro@8bytes.org>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: Ingo Molnar <mingo@redhat.com>
> Cc: Borislav Petkov <bp@alien8.de>
> Cc: "H. Peter Anvin" <hpa@zytor.com>
> Cc: kvm@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org
> ---
>  .../testing/selftests/kvm/include/kvm_util.h  |  1 +
>  .../selftests/kvm/include/x86_64/svm_util.h   |  2 ++
>  tools/testing/selftests/kvm/lib/kvm_util.c    | 24 +++++++++++--------
>  tools/testing/selftests/kvm/lib/x86_64/svm.c  | 13 ++++++++++
>  4 files changed, 30 insertions(+), 10 deletions(-)
>
> diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h
> index 010b59b13917..368e88305046 100644
> --- a/tools/testing/selftests/kvm/include/kvm_util.h
> +++ b/tools/testing/selftests/kvm/include/kvm_util.h
> @@ -80,6 +80,7 @@ struct vm_guest_mode_params {
>  };
>  extern const struct vm_guest_mode_params vm_guest_mode_params[];
>
> +int open_path_or_exit(const char *path, int flags);
>  int open_kvm_dev_path_or_exit(void);
>  int kvm_check_cap(long cap);
>  int vm_enable_cap(struct kvm_vm *vm, struct kvm_enable_cap *cap);
> diff --git a/tools/testing/selftests/kvm/include/x86_64/svm_util.h b/tools/testing/selftests/kvm/include/x86_64/svm_util.h
> index b7531c83b8ae..587fbe408b99 100644
> --- a/tools/testing/selftests/kvm/include/x86_64/svm_util.h
> +++ b/tools/testing/selftests/kvm/include/x86_64/svm_util.h
> @@ -46,4 +46,6 @@ static inline bool cpu_has_svm(void)
>         return ecx & CPUID_SVM;
>  }
>
> +int open_sev_dev_path_or_exit(void);
> +
>  #endif /* SELFTEST_KVM_SVM_UTILS_H */
> diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
> index 10a8ed691c66..06a6c04010fb 100644
> --- a/tools/testing/selftests/kvm/lib/kvm_util.c
> +++ b/tools/testing/selftests/kvm/lib/kvm_util.c
> @@ -31,6 +31,19 @@ static void *align(void *x, size_t size)
>         return (void *) (((size_t) x + mask) & ~mask);
>  }
>
> +int open_path_or_exit(const char *path, int flags)
> +{
> +       int fd;
> +
> +       fd = open(path, flags);
> +       if (fd < 0) {
> +               print_skip("%s not available (errno: %d)", path, errno);
> +               exit(KSFT_SKIP);
> +       }
> +
> +       return fd;
> +}
> +
>  /*
>   * Open KVM_DEV_PATH if available, otherwise exit the entire program.
>   *
> @@ -42,16 +55,7 @@ static void *align(void *x, size_t size)
>   */
>  static int _open_kvm_dev_path_or_exit(int flags)
>  {
> -       int fd;
> -
> -       fd = open(KVM_DEV_PATH, flags);
> -       if (fd < 0) {
> -               print_skip("%s not available, is KVM loaded? (errno: %d)",
> -                          KVM_DEV_PATH, errno);
> -               exit(KSFT_SKIP);
> -       }
> -
> -       return fd;
> +       return open_path_or_exit(KVM_DEV_PATH, flags);
>  }
>
>  int open_kvm_dev_path_or_exit(void)
> diff --git a/tools/testing/selftests/kvm/lib/x86_64/svm.c b/tools/testing/selftests/kvm/lib/x86_64/svm.c
> index 2ac98d70d02b..14a8618efa9c 100644
> --- a/tools/testing/selftests/kvm/lib/x86_64/svm.c
> +++ b/tools/testing/selftests/kvm/lib/x86_64/svm.c
> @@ -13,6 +13,8 @@
>  #include "processor.h"
>  #include "svm_util.h"
>
> +#define SEV_DEV_PATH "/dev/sev"
> +
>  struct gpr64_regs guest_regs;
>  u64 rflags;
>
> @@ -160,3 +162,14 @@ void nested_svm_check_supported(void)
>                 exit(KSFT_SKIP);
>         }
>  }
> +
> +/*
> + * Open SEV_DEV_PATH if available, otherwise exit the entire program.
> + *
> + * Return:
> + *   The opened file descriptor of /dev/sev.
> + */
> +int open_sev_dev_path_or_exit(void)
> +{
> +       return open_path_or_exit(SEV_DEV_PATH, 0);
> +}
> --
> 2.33.0.309.g3052b89438-goog
>

Reviewed-by: Marc Orr <marcorr@google.com>