[PATCH v2] arm64: mm: Fix the lockless page-table walk in show_pte()

[Will Deacon]

On Fri, 28 Aug 2026 19:41:31 +0200, Karl Mehltretter wrote:
> show_pte() walks page tables locklessly and can run with interrupts
> enabled. A concurrent teardown can free a table page while it is being
> walked. It can also clear a parent entry after show_pte() checked it; the
> regular pXd_offset() helpers then reread the cleared entry and can derive a
> bogus lower-level pointer and fault again.
> 
> Use the lockless offset helpers with the saved parent entries, as
> gup_fast() does, and pass the saved PMD to pte_offset_map().
> 
> [...]

Applied to arm64 (for-next/fixes), thanks!

[1/1] arm64: mm: Fix the lockless page-table walk in show_pte()
      https://git.kernel.org/arm64/c/a77644d009de

Cheers,
-- 
Will

https://fixes.arm64.dev
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