Re: [Intel-wired-lan] [PATCH net-next v11 12/12] libeth: xdp: access ->pp through netmem_desc instead of page

[Pavel Begunkov]

On 7/18/25 10:18, Pavel Begunkov wrote:
> On 7/18/25 02:14, Byungchul Park wrote:
...>>>>     include/linux/mm.h:4176:54: note: expected 'struct page *' but argument is of type 'const struct page *'
> > > >      static inline bool page_pool_page_is_pp(struct page *page)
> > > >                                              ~~~~~~~~~~~~~^~~~
> > >
> > > Oh.  page_pool_page_is_pp() in the mainline code already has this issue
> > > that the helper cannot take const struct page * as argument.
>
> Probably not, and probably for wrong reasons. netmem_ref is define
> as an integer, compilers cast away such const unlike const pointers.

Taking a look libeth, at least at the reported spot it does
page->pp->p.offset, that should be fine. And your problem
is caused by the is_pp check in pp_page_to_nmdesc().

--
Pavel Begunkov