netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Jamal Hadi Salim <jhs@mojatatu.com>
To: Jakub Kicinski <kuba@kernel.org>
Cc: davem@davemloft.net, netdev@vger.kernel.org, edumazet@google.com,
	 pabeni@redhat.com,
	Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>,
	 Davide Caratti <dcaratti@redhat.com>,
	xiyou.wangcong@gmail.com, jiri@resnulli.us,
	 shmulik.ladkani@gmail.com
Subject: Re: [PATCH net] net/sched: act_mirred: use the backlog for mirred ingress
Date: Wed, 14 Feb 2024 10:11:25 -0500	[thread overview]
Message-ID: <CAM0EoMmXrLv4aPo1btG2_oi4fTX=gZzO90jyHQzWvM26ZUFbww@mail.gmail.com> (raw)
In-Reply-To: <20240209235413.3717039-1-kuba@kernel.org>

On Fri, Feb 9, 2024 at 6:54 PM Jakub Kicinski <kuba@kernel.org> wrote:
>
> The test Davide added in commit ca22da2fbd69 ("act_mirred: use the backlog
> for nested calls to mirred ingress") hangs our testing VMs every 10 or so
> runs, with the familiar tcp_v4_rcv -> tcp_v4_rcv deadlock reported by
> lockdep.
>
> In the past there was a concern that the backlog indirection will
> lead to loss of error reporting / less accurate stats. But the current
> workaround does not seem to address the issue.
>
> Fixes: 53592b364001 ("net/sched: act_mirred: Implement ingress actions")
> Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
> Suggested-by: Davide Caratti <dcaratti@redhat.com>
> Link: https://lore.kernel.org/netdev/33dc43f587ec1388ba456b4915c75f02a8aae226.1663945716.git.dcaratti@redhat.com/
> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
> ---
> CC: jhs@mojatatu.com
> CC: xiyou.wangcong@gmail.com
> CC: jiri@resnulli.us
> CC: shmulik.ladkani@gmail.com
> ---
>  net/sched/act_mirred.c                             | 14 +++++---------
>  .../testing/selftests/net/forwarding/tc_actions.sh |  3 ---
>  2 files changed, 5 insertions(+), 12 deletions(-)
>
> diff --git a/net/sched/act_mirred.c b/net/sched/act_mirred.c
> index 93a96e9d8d90..35c366f043d9 100644
> --- a/net/sched/act_mirred.c
> +++ b/net/sched/act_mirred.c
> @@ -232,18 +232,14 @@ static int tcf_mirred_init(struct net *net, struct nlattr *nla,
>         return err;
>  }
>
> -static bool is_mirred_nested(void)
> -{
> -       return unlikely(__this_cpu_read(mirred_nest_level) > 1);
> -}
> -
> -static int tcf_mirred_forward(bool want_ingress, struct sk_buff *skb)
> +static int
> +tcf_mirred_forward(bool at_ingress, bool want_ingress, struct sk_buff *skb)
>  {
>         int err;
>
>         if (!want_ingress)
>                 err = tcf_dev_queue_xmit(skb, dev_queue_xmit);
> -       else if (is_mirred_nested())
> +       else if (!at_ingress)
>                 err = netif_rx(skb);
>         else
>                 err = netif_receive_skb(skb);
> @@ -319,9 +315,9 @@ static int tcf_mirred_to_dev(struct sk_buff *skb, struct tcf_mirred *m,
>
>                 skb_set_redirected(skb_to_send, skb_to_send->tc_at_ingress);
>
> -               err = tcf_mirred_forward(want_ingress, skb_to_send);
> +               err = tcf_mirred_forward(at_ingress, want_ingress, skb_to_send);
>         } else {
> -               err = tcf_mirred_forward(want_ingress, skb_to_send);
> +               err = tcf_mirred_forward(at_ingress, want_ingress, skb_to_send);
>         }
>
>         if (err) {
> diff --git a/tools/testing/selftests/net/forwarding/tc_actions.sh b/tools/testing/selftests/net/forwarding/tc_actions.sh
> index b0f5e55d2d0b..589629636502 100755
> --- a/tools/testing/selftests/net/forwarding/tc_actions.sh
> +++ b/tools/testing/selftests/net/forwarding/tc_actions.sh
> @@ -235,9 +235,6 @@ mirred_egress_to_ingress_tcp_test()
>         check_err $? "didn't mirred redirect ICMP"
>         tc_check_packets "dev $h1 ingress" 102 10
>         check_err $? "didn't drop mirred ICMP"
> -       local overlimits=$(tc_rule_stats_get ${h1} 101 egress .overlimits)
> -       test ${overlimits} = 10
> -       check_err $? "wrong overlimits, expected 10 got ${overlimits}"
>
>         tc filter del dev $h1 egress protocol ip pref 100 handle 100 flower
>         tc filter del dev $h1 egress protocol ip pref 101 handle 101 flower
> --
> 2.43.0
>


Doing a quick test of this and other patch i saw..

cheers,
jamal

  parent reply	other threads:[~2024-02-14 15:11 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-02-09 23:54 [PATCH net] net/sched: act_mirred: use the backlog for mirred ingress Jakub Kicinski
2024-02-12 14:51 ` Jamal Hadi Salim
2024-02-12 15:02   ` Jakub Kicinski
2024-02-12 15:11   ` Jamal Hadi Salim
2024-02-13 11:06     ` Paolo Abeni
2024-02-14  0:27       ` Jakub Kicinski
2024-02-14  3:40         ` Jakub Kicinski
2024-02-14 15:11 ` Jamal Hadi Salim [this message]
2024-02-14 15:28   ` Jamal Hadi Salim
2024-02-14 16:10     ` Davide Caratti
2024-02-15  0:31       ` Jakub Kicinski
2024-02-15 17:55         ` Davide Caratti
  -- strict thread matches above, loose matches on Subject: below --
2022-09-23 15:11 Davide Caratti
2022-09-25 18:08 ` Cong Wang
2022-10-04 17:40   ` Davide Caratti
2022-10-16 17:28     ` Cong Wang
2022-11-18 23:07 ` Peilin Ye

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to='CAM0EoMmXrLv4aPo1btG2_oi4fTX=gZzO90jyHQzWvM26ZUFbww@mail.gmail.com' \
    --to=jhs@mojatatu.com \
    --cc=davem@davemloft.net \
    --cc=dcaratti@redhat.com \
    --cc=edumazet@google.com \
    --cc=jiri@resnulli.us \
    --cc=kuba@kernel.org \
    --cc=marcelo.leitner@gmail.com \
    --cc=netdev@vger.kernel.org \
    --cc=pabeni@redhat.com \
    --cc=shmulik.ladkani@gmail.com \
    --cc=xiyou.wangcong@gmail.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).