On Sat, Oct 18, 2025 at 01:17:55PM -0400, Pasha Tatashin wrote: > Metadata is preserved via 512-bytes, which requires using slabs. Slabs
KHO memory preservation metadata is preserved in 512 byte chunks which requires their allocation from slab allocator. > are not safe to be used with KHO because of kfence, and because partial Please add more details why kfence is not safe here. > slabs may lead leaks to the next kernel. Change the size to be > PAGE_SIZE. > > While this change could potentially increase metadata overhead on > systems with sparsely preserved memory, this is being mitigated by > ongoing work to reduce sparseness during preservation via 1G guest > pages. Furthermore, this change aligns with future work on a stateless > KHO, which will also use page-sized bitmaps for its radix tree metadata. With the stateless memory preservation there would be no problem with kfence, right? Maybe we should accelerate the stateless preservation work? > Signed-off-by: Pasha Tatashin <[email protected]> -- Sincerely yours, Mike.
