Re: [PATCH v2] mm/hugetlb_cma: support percentage-based hugetlb_cma reservation

[David Hildenbrand (Arm)]

On 6/28/26 21:01, Sourav Panda wrote:
> Currently, hugetlb_cma reservation only supports absolute sizes (e.g.,
> hugetlb_cma=2G or hugetlb_cma=0:1G,1:1G). This can be restrictive in
> heterogeneous environments or when deploying common kernel command lines
> across machines with different memory capacities.
> 
> Add support for percentage-based hugetlb_cma reservation (e.g.,
> hugetlb_cma=20% or hugetlb_cma=0:20%,1:10%).
> 
> The percentage is calculated against the total memory (for global
> settings) or against the node-specific memory (for node-specific
> settings) using memblock APIs during early boot.
> 
> Signed-off-by: Sourav Panda <souravpanda@xxxxxxxxxx>
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> Closes: https://lore.kernel.org/oe-kbuild-all/202606262023.IKUrn01I-lkp@xxxxxxxxx/
> ---
> Link: https://lore.kernel.org/linux-mm/20260625215900.2151690-1-souravpanda@xxxxxxxxxx/ [v1]
> 
> v2:
> - Use mul_u64_u32_div() instead of mult_frac() to avoid 64-bit division on 32-bit architectures (Reported by kernel test robot).
> - Fix physical memory size truncation on 32-bit PAE by using phys_addr_t in memblock_node_memory_size() (Sashiko).
> - Fix boot parameter override logic to respect standard last-one-wins precedence by clearing opposite values during parsing and clearing node-specific values when global values are parsed.
>  .../admin-guide/kernel-parameters.txt         |  7 +-
>  mm/hugetlb_cma.c                              | 96 ++++++++++++++++++-
>  2 files changed, 97 insertions(+), 6 deletions(-)

What's the status of this? Reading the comments I assume a v3?

-- 
Cheers,

David