Re: [PATCH v2 3/4] arm64: hugetlb: Fix flush_hugetlb_tlb_range() invalidation level

[Catalin Marinas]

On Mon, Feb 17, 2025 at 02:04:16PM +0000, Ryan Roberts wrote:
> commit c910f2b65518 ("arm64/mm: Update tlb invalidation routines for
> FEAT_LPA2") changed the "invalidation level unknown" hint from 0 to
> TLBI_TTL_UNKNOWN (INT_MAX). But the fallback "unknown level" path in
> flush_hugetlb_tlb_range() was not updated. So as it stands, when trying
> to invalidate CONT_PMD_SIZE or CONT_PTE_SIZE hugetlb mappings, we will
> spuriously try to invalidate at level 0 on LPA2-enabled systems.
> 
> Fix this so that the fallback passes TLBI_TTL_UNKNOWN, and while we are
> at it, explicitly use the correct stride and level for CONT_PMD_SIZE and
> CONT_PTE_SIZE, which should provide a minor optimization.
> 
> Cc: stable@xxxxxxxxxxxxxxx
> Fixes: c910f2b65518 ("arm64/mm: Update tlb invalidation routines for FEAT_LPA2")
> Signed-off-by: Ryan Roberts <ryan.roberts@xxxxxxx>

Reviewed-by: Catalin Marinas <catalin.marinas@xxxxxxx>