On Fri, Nov 14, 2025 at 10:53:58AM -0500, Pasha Tatashin wrote: > Currently, clients of KHO must manually allocate memory (e.g., via > alloc_pages), calculate the page order, and explicitly call > kho_preserve_folio(). Similarly, cleanup requires separate calls to > unpreserve and free the memory. > > Introduce a high-level API to streamline this common pattern: > > - kho_alloc_preserve(size): Allocates physically contiguous, zeroed > memory and immediately marks it for preservation. > - kho_free_unpreserve(ptr, size): Unpreserves and frees the memory > in the current kernel. > - kho_free_restore(ptr, size): Restores the struct page state of > preserved memory in the new kernel and immediately frees it to the > page allocator.
It would have been nice to have it before patch 3 (Preserve FDT folio only once during initialization) and use kho_alloc_preserve() for KHO's own FDT. > Signed-off-by: Pasha Tatashin <[email protected]> > --- > include/linux/kexec_handover.h | 22 +++++-- > kernel/liveupdate/kexec_handover.c | 101 +++++++++++++++++++++++++++++ > 2 files changed, 116 insertions(+), 7 deletions(-) -- Sincerely yours, Mike.
