From: Pablo Neira Ayuso <pablo@netfilter.org>
To: Michael Lilja <michael.lilja@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>,
Eric Dumazet <edumazet@google.com>,
Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
Jonathan Corbet <corbet@lwn.net>,
Jozsef Kadlecsik <kadlec@netfilter.org>,
Florian Westphal <fw@strlen.de>,
netdev@vger.kernel.org, linux-doc@vger.kernel.org,
linux-kernel@vger.kernel.org, netfilter-devel@vger.kernel.org,
coreteam@netfilter.org
Subject: Re: [PATCH] Periodically flow expire from flow offload tables
Date: Wed, 2 Nov 2022 19:52:14 +0100 [thread overview]
Message-ID: <Y2K8XnFZvZeD4MEg@salvia> (raw)
In-Reply-To: <03E5D5FA-5A0D-4E5A-BA32-3FE51764C02E@gmail.com>
On Wed, Oct 26, 2022 at 09:40:11PM +0200, Michael Lilja wrote:
> Hi,
>
> I just quickly tried following the flow_offload_teardown() path instead of clearing IPS_OFFLOAD in flow_offload_del() and it does have some side effects. The flow is added again before the HW has actually reported it to be NF_FLOW_HW_DEAD.
>
> The sequence with my patch is:
> : Retire -> Remove from hw tables -> Remove from sw tables -> kfree(flow) -> flow_offload_add()
>
> But if flow_offload_teardown() is called on expire I see:
> : Retire -> Remove from hw tables -> flow_offload_add() -> Remove from sw tables -> kfree(flow)
>
> I need to investigate why this happens, maybe the IPS_OFFLOAD flag is cleared too early and should not be cleared until the flow is actually removed, like I do? Maybe the issue is not seen before because on timeout or flow_is_dying() no packet arrive to create the flow again prematurely?
Hm, IPS_OFFLOAD should be cleared from flow_offload_del() then, it is
cleared too early.
I'll post a fix for nf.git first then I propose to follow up on this
flowtable feature. I'll keep you on Cc.
next prev parent reply other threads:[~2022-11-02 18:52 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-10-23 17:16 [PATCH] Periodically flow expire from flow offload tables Michael Lilja
2022-10-25 11:05 ` Pablo Neira Ayuso
2022-10-25 12:36 ` Michael Lilja
2022-10-25 13:00 ` Pablo Neira Ayuso
2022-10-25 13:32 ` Michael Lilja
2022-10-26 10:50 ` Pablo Neira Ayuso
2022-10-26 17:36 ` Michael Lilja
2022-10-26 19:40 ` Michael Lilja
2022-11-02 18:52 ` Pablo Neira Ayuso [this message]
2022-11-02 19:52 ` Michael Lilja
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=Y2K8XnFZvZeD4MEg@salvia \
--to=pablo@netfilter.org \
--cc=corbet@lwn.net \
--cc=coreteam@netfilter.org \
--cc=davem@davemloft.net \
--cc=edumazet@google.com \
--cc=fw@strlen.de \
--cc=kadlec@netfilter.org \
--cc=kuba@kernel.org \
--cc=linux-doc@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=michael.lilja@gmail.com \
--cc=netdev@vger.kernel.org \
--cc=netfilter-devel@vger.kernel.org \
--cc=pabeni@redhat.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).