On Fri, Jan 16, 2026 at 11:22:14AM +0000, Pratyush Yadav wrote: > With 4k pages, a 32-bit nr_pages can span up to 16 TiB. While it is a > lot, there exist systems with terabytes of RAM. gup is also moving to > using long for nr_pages. Use unsigned long and make KHO future-proof. > > Suggested-by: Pasha Tatashin <[email protected]> > Signed-off-by: Pratyush Yadav <[email protected]>
Reviewed-by: Mike Rapoport (Microsoft) <[email protected]> > --- > > Changes in v2: > - New in v2. > > include/linux/kexec_handover.h | 6 +++--- > kernel/liveupdate/kexec_handover.c | 11 ++++++----- > 2 files changed, 9 insertions(+), 8 deletions(-) > > diff --git a/include/linux/kexec_handover.h b/include/linux/kexec_handover.h > index 5f7b9de97e8d..81814aa92370 100644 > --- a/include/linux/kexec_handover.h > +++ b/include/linux/kexec_handover.h > @@ -45,15 +45,15 @@ bool is_kho_boot(void); > > int kho_preserve_folio(struct folio *folio); > void kho_unpreserve_folio(struct folio *folio); > -int kho_preserve_pages(struct page *page, unsigned int nr_pages); > -void kho_unpreserve_pages(struct page *page, unsigned int nr_pages); > +int kho_preserve_pages(struct page *page, unsigned long nr_pages); > +void kho_unpreserve_pages(struct page *page, unsigned long nr_pages); > int kho_preserve_vmalloc(void *ptr, struct kho_vmalloc *preservation); > void kho_unpreserve_vmalloc(struct kho_vmalloc *preservation); > void *kho_alloc_preserve(size_t size); > void kho_unpreserve_free(void *mem); > void kho_restore_free(void *mem); > struct folio *kho_restore_folio(phys_addr_t phys); > -struct page *kho_restore_pages(phys_addr_t phys, unsigned int nr_pages); > +struct page *kho_restore_pages(phys_addr_t phys, unsigned long nr_pages); > void *kho_restore_vmalloc(const struct kho_vmalloc *preservation); > int kho_add_subtree(const char *name, void *fdt); > void kho_remove_subtree(void *fdt); > diff --git a/kernel/liveupdate/kexec_handover.c > b/kernel/liveupdate/kexec_handover.c > index 9dc51fab604f..709484fbf9fd 100644 > --- a/kernel/liveupdate/kexec_handover.c > +++ b/kernel/liveupdate/kexec_handover.c > @@ -222,7 +222,8 @@ static int __kho_preserve_order(struct kho_mem_track > *track, unsigned long pfn, > static struct page *kho_restore_page(phys_addr_t phys, bool is_folio) > { > struct page *page = pfn_to_online_page(PHYS_PFN(phys)); > - unsigned int nr_pages, ref_cnt; > + unsigned long nr_pages; > + unsigned int ref_cnt; > union kho_page_info info; > > if (!page) > @@ -249,7 +250,7 @@ static struct page *kho_restore_page(phys_addr_t phys, > bool is_folio) > * count of 1 > */ > ref_cnt = is_folio ? 0 : 1; > - for (unsigned int i = 1; i < nr_pages; i++) > + for (unsigned long i = 1; i < nr_pages; i++) > set_page_count(page + i, ref_cnt); > > if (is_folio && info.order) > @@ -283,7 +284,7 @@ EXPORT_SYMBOL_GPL(kho_restore_folio); > * > * Return: 0 on success, error code on failure > */ > -struct page *kho_restore_pages(phys_addr_t phys, unsigned int nr_pages) > +struct page *kho_restore_pages(phys_addr_t phys, unsigned long nr_pages) > { > const unsigned long start_pfn = PHYS_PFN(phys); > const unsigned long end_pfn = start_pfn + nr_pages; > @@ -829,7 +830,7 @@ EXPORT_SYMBOL_GPL(kho_unpreserve_folio); > * > * Return: 0 on success, error code on failure > */ > -int kho_preserve_pages(struct page *page, unsigned int nr_pages) > +int kho_preserve_pages(struct page *page, unsigned long nr_pages) > { > struct kho_mem_track *track = &kho_out.track; > const unsigned long start_pfn = page_to_pfn(page); > @@ -873,7 +874,7 @@ EXPORT_SYMBOL_GPL(kho_preserve_pages); > * kho_preserve_pages() call. Unpreserving arbitrary sub-ranges of larger > * preserved blocks is not supported. > */ > -void kho_unpreserve_pages(struct page *page, unsigned int nr_pages) > +void kho_unpreserve_pages(struct page *page, unsigned long nr_pages) > { > struct kho_mem_track *track = &kho_out.track; > const unsigned long start_pfn = page_to_pfn(page); > -- > 2.52.0.457.g6b5491de43-goog > -- Sincerely yours, Mike.
