Re: [PATCH net] xen-netfront: Add missing skb_mark_for_recycle

[Arthur Borsboom <arthurborsboom@xxxxxxxxx>]

On Fri, 29 Mar 2024 at 10:47, Arthur Borsboom <arthurborsboom@xxxxxxxxx> wrote:
>
> On Wed, 27 Mar 2024 at 13:15, Jesper Dangaard Brouer <hawk@xxxxxxxxxx> wrote:
> >
> > Notice that skb_mark_for_recycle() is introduced later than fixes tag in
> > 6a5bcd84e886 ("page_pool: Allow drivers to hint on SKB recycling").
> >
> > It is believed that fixes tag were missing a call to 
> > page_pool_release_page()
> > between v5.9 to v5.14, after which is should have used 
> > skb_mark_for_recycle().
> > Since v6.6 the call page_pool_release_page() were removed (in 535b9c61bdef
> > ("net: page_pool: hide page_pool_release_page()") and remaining callers
> > converted (in commit 6bfef2ec0172 ("Merge branch
> > 'net-page_pool-remove-page_pool_release_page'")).
> >
> > This leak became visible in v6.8 via commit dba1b8a7ab68 ("mm/page_pool: 
> > catch
> > page_pool memory leaks").
> >
> > Fixes: 6c5aa6fc4def ("xen networking: add basic XDP support for 
> > xen-netfront")
> > Reported-by: Arthur Borsboom <arthurborsboom@xxxxxxxxx>
> > Signed-off-by: Jesper Dangaard Brouer <hawk@xxxxxxxxxx>
> > ---
> > Compile tested only, can someone please test this
>
> I have tested this patch on Xen 4.18.1 with VM (Arch Linux) kernel 6.9.0-rc1.
>
> Without the patch there are many trace traces and cloning the Linux
> mainline git repository resulted in failures (same with kernel 6.8.1).
> The patched kernel 6.9.0-rc1 performs as expected; cloning the git
> repository was successful and no kernel traces observed.
> Hereby my tested by:
>
> Tested-by: Arthur Borsboom <arthurborsboom@xxxxxxxxx>
>
>
>
> >  drivers/net/xen-netfront.c |    1 +
> >  1 file changed, 1 insertion(+)
> >
> > diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c
> > index ad29f370034e..8d2aee88526c 100644
> > --- a/drivers/net/xen-netfront.c
> > +++ b/drivers/net/xen-netfront.c
> > @@ -285,6 +285,7 @@ static struct sk_buff 
> > *xennet_alloc_one_rx_buffer(struct netfront_queue *queue)
> >                 return NULL;
> >         }
> >         skb_add_rx_frag(skb, 0, page, 0, 0, PAGE_SIZE);
> > +       skb_mark_for_recycle(skb);
> >
> >         /* Align ip header to a 16 bytes boundary */
> >         skb_reserve(skb, NET_IP_ALIGN);
> >
> >

I don't see this patch yet in linux-next.

https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/log

Any idea in which kernel release this patch will be included?