Re: [PATCH v2 3/4] arm64: hugetlb: Fix flush_hugetlb_tlb_range() invalidation level
From: Anshuman Khandual <hidden>
Date: 2025-02-19 08:56:34
Also in:
linux-mm, lkml, stable
On 2/17/25 19:34, 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@vger.kernel.org
Fixes: c910f2b65518 ("arm64/mm: Update tlb invalidation routines for FEAT_LPA2")
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>LGTM Reviewed-by: Anshuman Khandual <redacted>
quoted hunk ↗ jump to hunk
--- arch/arm64/include/asm/hugetlb.h | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-)diff --git a/arch/arm64/include/asm/hugetlb.h b/arch/arm64/include/asm/hugetlb.h index 03db9cb21ace..07fbf5bf85a7 100644 --- a/arch/arm64/include/asm/hugetlb.h +++ b/arch/arm64/include/asm/hugetlb.h@@ -76,12 +76,22 @@ 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) { +#ifndef __PAGETABLE_PMD_FOLDED + case PUD_SIZE: + __flush_tlb_range(vma, start, end, PUD_SIZE, false, 1); + break; +#endif + 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 */