Re: [PATCH v2 1/3] KVM: arm64: selftests: Support five-level stage-1 page tables

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] The `type` array in `pte_dump` is missing the entry for P4D, causing it to print an empty string for level 0.
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commit ec0c73a180f67ed464cb14e88f74413194ff828e
Author: Itaru Kitayama <itaru.kitayama@fujitsu.com>

KVM: arm64: selftests: Support five-level stage-1 page tables

This commit adds support for five-level stage-1 page tables in the ARM64
KVM selftests. It extends the page-table helpers and level validation to
handle the new architectural level -1. This enables testing 52-bit VA
configurations with a 4K translation granule.

> diff --git a/tools/testing/selftests/kvm/lib/arm64/processor.c b/tools/testing/selftests/kvm/lib/arm64/processor.c
> index 01325bf4d36fc..b589368bf8222 100644
> --- a/tools/testing/selftests/kvm/lib/arm64/processor.c
> +++ b/tools/testing/selftests/kvm/lib/arm64/processor.c

[ ... ]

> @@ -214,7 +249,7 @@ u64 *virt_get_pte_hva_at_level(struct kvm_vm *vm, gva_t gva, int level)
>  			goto unmapped_gva;
>  		break;
>  	default:
> -		TEST_FAIL("Page table levels must be 2, 3, or 4");
> +		TEST_FAIL("Page table levels must be 2, 3, 4, or 5");
>  	}
>  
>  	return ptep;

[Severity: Low]
Does this change miss updating the string names in pte_dump()?

Looking at pte_dump() in tools/testing/selftests/kvm/lib/arm64/processor.c,
the type array maps the translation level to its string name:

	static const char * const type[] = { "", "pud", "pmd", "pte" };

When the test framework is compiled with DEBUG and dumps a 5-level page
table, virt_arch_dump() calculates the starting level for pte_dump() as 0.
Since the array was not updated to include "p4d", debug output for level 0
will print an empty string instead of "p4d".

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Sashiko AI review · https://sashiko.dev/#/patchset/20260914-arm64-52bit-va-v2-0-3911cb9d4ad4@fujitsu.com?part=1