Re: [PATCH net 2/2] selftests: net: packetdrill: add test for negative sk_forward_alloc in tcp_wmem_schedule()
From: Eric Dumazet
Date: Fri Oct 16 2026 - 04:24:42 EST
Le ven. 16 oct. 2026 à 10:22, Eric Dumazet <edumazet@xxxxxxxxxx> a écrit :
>
> Le ven. 16 oct. 2026 à 09:54, Kuniyuki Iwashima <kuniyu@xxxxxxxxxx> a écrit :
> >
> > On Thu, Oct 15, 2026 at 12:37 AM Octavian Purdila <tavip@xxxxxxxxxx> wrote:
> > >
> > > Add a packetdrill test that drives sk->sk_forward_alloc negative via
> > > tcp_collapse() on the receive queue while sk->sk_wmem_queued exceeds
> > > sysctl_tcp_wmem[0], and verifies that a subsequent non-blocking write()
> > > under TCP memory pressure fails with EAGAIN rather than returning a
> > > negative copy length from tcp_wmem_schedule() and failing with EFAULT.
> > >
> > > Assisted-by: LLM
> > > Signed-off-by: Octavian Purdila <tavip@xxxxxxxxxx>
> >
> > Reviewed-by: Kuniyuki Iwashima <kuniyu@xxxxxxxxxx>
> >
> > Thanks !
>
> Are you sure this test is passing on arches with 6K pages (as some
> arm64 and ppc64 platforms) ?
This was meant to read : 64K pages.
> We might need to add a check to only run it on 4K platforms.