Re: [PATCH V3 0/2] arm64/mm: Enable batched TLB flush in unmap_hotplug_range()

[Anshuman Khandual]

On 24/02/26 11:54 AM, Anshuman Khandual wrote:
> This series enables batched TLB flush in unmap_hotplug_range() which avoids
> individual page TLB flush for potential CONT blocks in linear mapping while
> also improving performance due to range based TLB operation along with less
> synchronization barrier instructions.
> 
> It also now rejects memory removal that might split a leaf entry in kernel
> mapping, which would have otherwise required re-structuring using the break
> before make (BBM) semantics. But kernel cannot tolerate BBM, so remapping to
> fine grained leaves would not be possible on systems without BBML2_NOABORT.
> 
> This series applies on 7.0-rc1 and tested on KVM guest.
> 
> Changes in V3:
> 
> - Fixed some typos in the commit message for [PATCH 2/2]
> - Dropped copying stable@xxxxxxxxxxxxxxx per Ryan
> 
> Changes in V2:
> 
> https://lore.kernel.org/all/20260203130348.612150-1-anshuman.khandual@xxxxxxx/
> 
> - Renamed split_kernel_leaf_boundary() as addr_splits_kernel_leaf()
> - Dropped pte_valid()/pmd_leaf() before checking pte_cont()/pmd_cont()
> - Changed and dropped variables in can_unmap_without_split()
> - Moved can_unmap_without_split() after boot memory check
> - Renamed 'prevent_bootmem' as 'prevent_memory' across the board
> - Updated commit message in both patches
> > Changes in V1:
> 
> - https://lore.kernel.org/all/20260202042617.504183-1-anshuman.khandual@xxxxxxx/
> 
> Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
> Cc: Will Deacon <will@xxxxxxxxxx>
> Cc: Ryan Roberts <ryan.roberts@xxxxxxx>
> Cc: Yang Shi <yang@xxxxxxxxxxxxxxxxxxxxxx>
> Cc: Christoph Lameter <cl@xxxxxxxxxx>
> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> Cc: linux-kernel@xxxxxxxxxxxxxxx
> 
> Anshuman Khandual (2):
>   arm64/mm: Enable batched TLB flush in unmap_hotplug_range()
>   arm64/mm: Reject memory removal that splits a kernel leaf mapping
> 
>  arch/arm64/mm/mmu.c | 236 ++++++++++++++++++++++++++++++++++++++++----
>  1 file changed, 216 insertions(+), 20 deletions(-)
> 

Gentle ping. Any updates on this ?