Re: [V2 PATCH 3/8] KVM: selftests: Add arch specific post vm load setup

[David Matlack <dmatlack@google.com>]

On Thu, Sep 15, 2022 at 12:04:43AM +0000, Vishal Annapurve wrote:
> Add arch specific API kvm_selftest_post_vm_elf_load to possibly communicate
> information to VM that is already known to selftest VMM logic.
> 
> This API will be used in followup commit to convey cpu vendor type to the
> guest vm.
> 
> Suggested-by: Sean Christopherson <seanjc@google.com>
> Signed-off-by: Vishal Annapurve <vannapurve@google.com>
> ---
>  tools/testing/selftests/kvm/include/kvm_util_base.h | 4 ++++
>  tools/testing/selftests/kvm/lib/aarch64/processor.c | 4 ++++
>  tools/testing/selftests/kvm/lib/elf.c               | 2 ++
>  tools/testing/selftests/kvm/lib/riscv/processor.c   | 4 ++++
>  tools/testing/selftests/kvm/lib/s390x/processor.c   | 4 ++++
>  tools/testing/selftests/kvm/lib/x86_64/processor.c  | 4 ++++
>  6 files changed, 22 insertions(+)
> 
> diff --git a/tools/testing/selftests/kvm/include/kvm_util_base.h b/tools/testing/selftests/kvm/include/kvm_util_base.h
> index 98edbbda9f97..73cfee3ebd76 100644
> --- a/tools/testing/selftests/kvm/include/kvm_util_base.h
> +++ b/tools/testing/selftests/kvm/include/kvm_util_base.h
> @@ -839,4 +839,8 @@ static inline int __vm_disable_nx_huge_pages(struct kvm_vm *vm)
>   */
>  void kvm_selftest_arch_init(void);
>  
> +/*
> + * API to execute architecture specific setup after loading the vm elf.

It's not a "vm elf" per-se, it's "loading the elf into the VM". How
about:

/*
 * API to execute arch-specific logic after loading the selftest ELF image
 * into the VM.
 */

> + */
> +void kvm_arch_post_vm_elf_load(struct kvm_vm *vm);
>  #endif /* SELFTEST_KVM_UTIL_BASE_H */
> diff --git a/tools/testing/selftests/kvm/lib/aarch64/processor.c b/tools/testing/selftests/kvm/lib/aarch64/processor.c
> index 2281d6c5d02f..12627c560f66 100644
> --- a/tools/testing/selftests/kvm/lib/aarch64/processor.c
> +++ b/tools/testing/selftests/kvm/lib/aarch64/processor.c
> @@ -528,3 +528,7 @@ void kvm_selftest_arch_init(void)
>  {
>  	guest_modes_append_default();
>  }
> +
> +void kvm_arch_post_vm_elf_load(struct kvm_vm *vm)
> +{
> +}
> diff --git a/tools/testing/selftests/kvm/lib/elf.c b/tools/testing/selftests/kvm/lib/elf.c
> index 9f54c098d9d0..b8963a7146ce 100644
> --- a/tools/testing/selftests/kvm/lib/elf.c
> +++ b/tools/testing/selftests/kvm/lib/elf.c
> @@ -189,4 +189,6 @@ void kvm_vm_elf_load(struct kvm_vm *vm, const char *filename)
>  				phdr.p_filesz);
>  		}
>  	}
> +
> +	kvm_arch_post_vm_elf_load(vm);
>  }

Same suggestion here as the previous patch: Use __weak to define a
default no-op implementation of kvm_arch_post_vm_elf_load().

> diff --git a/tools/testing/selftests/kvm/lib/riscv/processor.c b/tools/testing/selftests/kvm/lib/riscv/processor.c
> index 26660dd2ba78..4491c0d4be45 100644
> --- a/tools/testing/selftests/kvm/lib/riscv/processor.c
> +++ b/tools/testing/selftests/kvm/lib/riscv/processor.c
> @@ -366,3 +366,7 @@ void assert_on_unhandled_exception(struct kvm_vcpu *vcpu)
>  void kvm_selftest_arch_init(void)
>  {
>  }
> +
> +void kvm_arch_post_vm_elf_load(struct kvm_vm *vm)
> +{
> +}
> diff --git a/tools/testing/selftests/kvm/lib/s390x/processor.c b/tools/testing/selftests/kvm/lib/s390x/processor.c
> index 8654ec74009a..332501b3693f 100644
> --- a/tools/testing/selftests/kvm/lib/s390x/processor.c
> +++ b/tools/testing/selftests/kvm/lib/s390x/processor.c
> @@ -222,3 +222,7 @@ void assert_on_unhandled_exception(struct kvm_vcpu *vcpu)
>  void kvm_selftest_arch_init(void)
>  {
>  }
> +
> +void kvm_arch_post_vm_elf_load(struct kvm_vm *vm)
> +{
> +}
> diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c
> index 20bf125f9363..25ae972f5c71 100644
> --- a/tools/testing/selftests/kvm/lib/x86_64/processor.c
> +++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c
> @@ -1315,3 +1315,7 @@ bool vm_is_unrestricted_guest(struct kvm_vm *vm)
>  void kvm_selftest_arch_init(void)
>  {
>  }
> +
> +void kvm_arch_post_vm_elf_load(struct kvm_vm *vm)
> +{
> +}
> -- 
> 2.37.2.789.g6183377224-goog
>