On Fri, Jul 18, 2025 at 10:32:38AM +0100, Pavel Begunkov wrote: > 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(). Exactly, but you asked me to add the check, DEBUG_NET_WARN_ON_ONCE(!page_pool_page_is_pp(p)) in pp_page_to_nmdesc(). What I meant was, in order to apply that, page_pool_page_is_pp() should take 'const struct page *' as argument. I think it's good idea to change the proto type like, as you said: static inline bool page_pool_page_is_pp(const struct page *page); Thanks. Byungchul > > -- > Pavel Begunkov >
