Re: [PATCH v10 5/5] KVM: arm64: Register ptdump with debugfs on guest creation

[Marc Zyngier]

On Mon, 09 Sep 2024 13:47:21 +0100,
Sebastian Ene <sebastianene@xxxxxxxxxx> wrote:
> 
> While arch/*/mem/ptdump handles the kernel pagetable dumping code,
> introduce KVM/ptdump to show the guest stage-2 pagetables. The
> separation is necessary because most of the definitions from the
> stage-2 pagetable reside in the KVM path and we will be invoking
> functionality specific to KVM. Introduce the PTDUMP_STAGE2_DEBUGFS config.
> 
> When a guest is created, register a new file entry under the guest
> debugfs dir which allows userspace to show the contents of the guest
> stage-2 pagetables when accessed.
> 
> Signed-off-by: Sebastian Ene <sebastianene@xxxxxxxxxx>
> Reviewed-by: Vincent Donnefort <vdonnefort@xxxxxxxxxx>
> ---
>  arch/arm64/include/asm/kvm_host.h |   6 +
>  arch/arm64/kvm/Kconfig            |  17 ++
>  arch/arm64/kvm/Makefile           |   1 +
>  arch/arm64/kvm/arm.c              |   1 +
>  arch/arm64/kvm/ptdump.c           | 268 ++++++++++++++++++++++++++++++
>  5 files changed, 293 insertions(+)
>  create mode 100644 arch/arm64/kvm/ptdump.c
> 
> diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
> index a33f5996ca9f..4acd589f086b 100644
> --- a/arch/arm64/include/asm/kvm_host.h
> +++ b/arch/arm64/include/asm/kvm_host.h
> @@ -1473,4 +1473,10 @@ void kvm_set_vm_id_reg(struct kvm *kvm, u32 reg, u64 val);
>  		(pa + pi + pa3) == 1;					\
>  	})
>  
> +#ifdef CONFIG_PTDUMP_STAGE2_DEBUGFS
> +void kvm_s2_ptdump_create_debugfs(struct kvm *kvm);
> +#else
> +static inline void kvm_s2_ptdump_create_debugfs(struct kvm *kvm) {}
> +#endif /* CONFIG_PTDUMP_STAGE2_DEBUGFS */
> +

I made the executive decision to move this to kvm_mmu.h, as this is
slightly more logical.

Thanks,

	M.

-- 
Without deviation from the norm, progress is not possible.