Re: [PATCH v2] arm64/mm: Check the requested PFN range during memory removal
Will Deacon <[email protected]>
| Newsgroups | org.kernel.vger.linux-cxl,org.infradead.lists.linux-arm-kernel,org.kernel.vger.linux-kernel |
|---|---|
| Message-ID | <[email protected]> |
On Tue, 21 Jul 2026 18:00:26 +0800, Richard Cheng wrote:
> prevent_memory_remove_notifier() advances pfn while scanning the requested
> range for early memory. When the loop completes, pfn is at or beyond
> end_pfn. Passing it to can_unmap_without_split() therefore checks a range
> after the one being offlined.
>
> Consequently, a valid request can be rejected based on the following
> range, while a request that would split a leaf mapping can be accepted if
> the shifted range can be unmapped without a split. This was observed with
> CXL DAX memory, where the final memory block was incorrectly allowed to
> be offlined.
>
> [...]
Applied to arm64 (for-next/fixes), thanks!
[1/1] arm64/mm: Check the requested PFN range during memory removal
https://git.kernel.org/arm64/c/285f90a4d1141
Cheers,
--
Will
https://fixes.arm64.dev
https://next.arm64.dev
https://will.arm64.dev