Re: [PATCH v3 02/17] kexec: Extract kexec_free_segment_cma() from kimage_free_cma()

[Mike Rapoport]

Hi,

> kimage_free_cma() relies on image->nr_segments to iterate over segments.
> When an architecture loader (e.g., arm64) truncates nr_segments on a
> mid-way failure, CMA pages allocated beyond the new boundary become
> unreachable, causing silent memory leaks.
> 
> Extract the per-segment freeing logic into the exported helper
> kexec_free_segment_cma(), so that architecture loaders can release
> individual segments before nr_segments is truncated. Refactor
> kimage_free_cma() to loop over the new helper, preserving existing
> behavior.
> 
> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> Cc: Baoquan He <baoquan.he@xxxxxxxxx>
> Cc: Mike Rapoport <rppt@xxxxxxxxxx>
> Cc: Pasha Tatashin <pasha.tatashin@xxxxxxxxxx>
> Cc: Pratyush Yadav <pratyush@xxxxxxxxxx>
> Signed-off-by: Jinjie Ruan <ruanjinjie@xxxxxxxxxx>
>
> diff --git a/include/linux/kexec.h b/include/linux/kexec.h
> index 83c296c0eb6cc..d7c83938dfd3d 100644
> --- a/include/linux/kexec.h
> +++ b/include/linux/kexec.h
> @@ -533,6 +533,7 @@ extern bool kexec_file_dbg_print;
>  
>  extern void *kimage_map_segment(struct kimage *image, int idx);
>  extern void kimage_unmap_segment(void *buffer);
> +extern void kexec_free_segment_cma(struct kimage *image, unsigned long idx);

No need for extern, even though it's inconsistent with old declarations.

-- 
Sincerely yours,
Mike.