On Tue, Oct 21 2025, Pasha Tatashin wrote: > Allow users of KHO to cancel the previous preservation by adding the > necessary interfaces to unpreserve folio and pages. > > Signed-off-by: Pasha Tatashin <[email protected]> > --- > include/linux/kexec_handover.h | 12 +++++ > kernel/kexec_handover.c | 85 ++++++++++++++++++++++++++++------ > 2 files changed, 84 insertions(+), 13 deletions(-) > [...] > > +/** > + * kho_unpreserve_pages - unpreserve contiguous pages. > + * @page: first page in the list. > + * @nr_pages: number of pages. > + * > + * Instructs KHO to unpreserve @nr_pages contigious pages starting from > @page.
s/contigious/contiguous. Also drop the extra space after it. > + * This call must exactly match a granularity at which memory was originally > + * preserved by kho_preserve_pages, call with the same @page and > + * @nr_pages). Unpreserving arbitrary sub-ranges of larger preserved blocks > is Stray closing parenthesis here. Perhaps a rewording to: "This must be called with the same @page and @nr_pages as the corresponding kho_preserve_pages() call. Unpreserving arbitrary..." Other than this, Reviewed-by: Pratyush Yadav <[email protected]> > + * not supported. > + * > + * Return: 0 on success, error code on failure > + */ > +int kho_unpreserve_pages(struct page *page, unsigned int nr_pages) > +{ > + struct kho_mem_track *track = &kho_out.track; > + const unsigned long start_pfn = page_to_pfn(page); > + const unsigned long end_pfn = start_pfn + nr_pages; > + > + if (kho_out.finalized) > + return -EBUSY; > + > + __kho_unpreserve(track, start_pfn, end_pfn); > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(kho_unpreserve_pages); > + > struct kho_vmalloc_hdr { > DECLARE_KHOSER_PTR(next, struct kho_vmalloc_chunk *); > }; -- Regards, Pratyush Yadav
