On 4/24/26 20:41, Matthew Wilcox wrote: > On Tue, Apr 21, 2026 at 06:01:10PM -0400, Michael S. Tsirkin wrote: >> Thread a user virtual address from vma_alloc_folio() down through >> the page allocator to post_alloc_hook(). This is plumbing preparation >> for a subsequent patch that will use user_addr to call folio_zero_user() >> for cache-friendly zeroing of user pages. >> >> The user_addr is stored in struct alloc_context and flows through: >> vma_alloc_folio -> folio_alloc_mpol -> __alloc_pages_mpol -> >> __alloc_frozen_pages -> get_page_from_freelist -> prep_new_page -> >> post_alloc_hook > > I don't like this. I think we should instead lift the zeroing from > post_alloc_hook() to the callers of __alloc_frozen_pages().
I don't think so. In particular how zeroing optimizations are related to buddy details (tag zeroing, kasan unpoisoning, init_on_alloc/init_on_free, now pre-zeroing). > > I don't understand why you want to remove the double-zeroing of memory > when the user has asked for zero_on_alloc. They asked for stupid things, > let them bear the cost. That's not how the world works :) -- Cheers, David
