On 2/5/25 20:39, 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>
> ---
> arch/arm64/include/asm/hugetlb.h | 20 ++++++++++++++------
> 1 file changed, 14 insertions(+), 6 deletions(-)
>
> diff --git a/arch/arm64/include/asm/hugetlb.h b/arch/arm64/include/asm/hugetlb.h
> index 03db9cb21ace..8ab9542d2d22 100644
> --- a/arch/arm64/include/asm/hugetlb.h
> +++ b/arch/arm64/include/asm/hugetlb.h
> @@ -76,12 +76,20 @@ static inline void flush_hugetlb_tlb_range(struct vm_area_struct *vma,
> {
> unsigned long stride = huge_page_size(hstate_vma(vma));
>
> - if (stride == PMD_SIZE)
> - __flush_tlb_range(vma, start, end, stride, false, 2);
> - else if (stride == PUD_SIZE)
> - __flush_tlb_range(vma, start, end, stride, false, 1);
> - else
> - __flush_tlb_range(vma, start, end, PAGE_SIZE, false, 0);
> + switch (stride) {
> + case PUD_SIZE:
> + __flush_tlb_range(vma, start, end, PUD_SIZE, false, 1);
> + break;
Just wondering - should not !__PAGETABLE_PMD_FOLDED and pud_sect_supported()
checks also be added here for this PUD_SIZE case ?
> + case CONT_PMD_SIZE:
> + case PMD_SIZE:
> + __flush_tlb_range(vma, start, end, PMD_SIZE, false, 2);
> + break;
> + case CONT_PTE_SIZE:
> + __flush_tlb_range(vma, start, end, PAGE_SIZE, false, 3);
> + break;
> + default:
> + __flush_tlb_range(vma, start, end, PAGE_SIZE, false, TLBI_TTL_UNKNOWN);
> + }
> }
>
> #endif /* __ASM_HUGETLB_H */
