Re: [PATCH 0/4] drivers/net: replace __get_free_pages() with kmalloc()
Simon Horman <[email protected]> Tue, 7 Jul 2026 15:46:01 +0100
| Newsgroups | org.infradead.lists.b43-dev,org.kernel.vger.linux-kernel,org.kernel.vger.linux-wireless,org.kernel.vger.netdev,org.kvack.linux-mm |
|---|---|
| Message-ID | <[email protected]> |
On Wed, Jul 01, 2026 at 04:59:09PM +0300, Mike Rapoport (Microsoft) wrote: > This is a (small) part of larger work of replacing page allocator calls > with kmalloc. > > My initial intention a few month ago was to remove ugly casts [1], but then > willy pointed out that Linus objected to something like this [2] and it > looks like more than a decade old technical debt. > > Largely, anything that doesn't need struct page (or a memdesc in the > future) should just use kmalloc() or kvmalloc() to allocate memory. > kmalloc() guarantees alignment, physical contiguity and working > virt_to_phys() and beside nicer API that returns void * on alloc and > doesn't require to know the allocation size on free, kmalloc() provides > better debugging capabilities than page allocator. > > Another thing is that touching these allocation sites gives the reviewers > opportunity to see if a PAGE_SIZE buffer is actually needed or maybe > another size is appropriate. > > For larger allocations that don't need physically contiguous memory > kvmalloc() can be a better option that __get_free_pages() because under > memory pressure it's is easier to allocate several order-0 pages than a > physically contiguous chunk with the same number of pages. > > And last, but not least, removing needless calls to page allocator should > help with memdesc (aka project folio) conversion. There will be way less > places to audit to see if the user was actually using struct page. > > Also in git: > https://git.kernel.org/pub/scm/linux/kernel/git/rppt/linux.git gfp-to-kmalloc/drivers-net-wireless > > [1] https://lore.kernel.org/all/[email protected]/ > [2] https://lore.kernel.org/all/CA+55aFwp4iy4rtX2gE2WjBGFL=NxMVnoFeHqYa2j1dYOMMGqxg@mail.gmail.com/ > > --- > Changes in v2: > - split out wireless drivers from a larger set > - use kzalloc() instead of kmalloc() + memset in b43legacy > > v1: https://patch.msgid.link/[email protected] For the series: Reviewed-by: Simon Horman <[email protected]> _______________________________________________ b43-dev mailing list [email protected] http://lists.infradead.org/mailman/listinfo/b43-dev