linux-kernel - Re: [Intel-wired-lan] [PATCH net-next v11 12/12] libeth: xdp: access ->pp through netmem

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <1fe747ea-56ce-4418-92cb-057d989e3732@gmail.com>
Date: Fri, 18 Jul 2025 10:32:38 +0100
From: Pavel Begunkov <asml.silence@...il.com>
To: Byungchul Park <byungchul@...com>, kernel test robot <lkp@...el.com>
Cc: willy@...radead.org, netdev@...r.kernel.org,
 oe-kbuild-all@...ts.linux.dev, linux-kernel@...r.kernel.org,
 linux-mm@...ck.org, kernel_team@...ynix.com, almasrymina@...gle.com,
 ilias.apalodimas@...aro.org, harry.yoo@...cle.com,
 akpm@...ux-foundation.org, andrew+netdev@...n.ch, toke@...hat.com,
 david@...hat.com, Liam.Howlett@...cle.com, vbabka@...e.cz, rppt@...nel.org,
 surenb@...gle.com, mhocko@...e.com, linux-rdma@...r.kernel.org,
 bpf@...r.kernel.org, vishal.moola@...il.com, hannes@...xchg.org,
 ziy@...dia.com, jackmanb@...gle.com, wei.fang@....com, shenwei.wang@....com,
 xiaoning.wang@....com, davem@...emloft.net, edumazet@...gle.com,
 kuba@...nel.org
Subject: Re: [Intel-wired-lan] [PATCH net-next v11 12/12] libeth: xdp: access
 ->pp through netmem_desc instead of page

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