From: Stefano Brivio <sbrivio@redhat.com>
To: Arturo Borrero Gonzalez <arturo@netfilter.org>
Cc: "netfilter-devel@vger.kernel.org" <netfilter-devel@vger.kernel.org>
Subject: Re: nft_pipapo_avx2_lookup backtrace in linux 5.10
Date: Sat, 8 May 2021 03:00:46 +0200 [thread overview]
Message-ID: <20210508030046.4ae872f6@redhat.com> (raw)
In-Reply-To: <a044a8bb-e7cd-35e5-9602-0879f872656c@netfilter.org>
On Fri, 7 May 2021 13:12:43 +0200
Arturo Borrero Gonzalez <arturo@netfilter.org> wrote:
> However, the nft ruleset is quite simple. It should be possible for you to grab
> a similar arch CPU, introduce the ruleset and generate some traffic to trigger
> the lookup(), no?
Unfortunately, this has little to do with the ruleset, it's rather
about the fact that a kthread using the FPU gets interrupted by
net_rx_action() which ends up in a call to nft_pipapo_avx2_lookup(),
which also uses the FPU.
The amount of luck I'd need to hit this with some ext4 worklaod
together with packet classification discourages me from even trying. ;)
But luckily my mistake here looks simple enough to fix.
--
Stefano
next prev parent reply other threads:[~2021-05-08 1:00 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-05-07 9:26 nft_pipapo_avx2_lookup backtrace in linux 5.10 Arturo Borrero Gonzalez
2021-05-07 10:35 ` Florian Westphal
2021-05-07 10:52 ` Stefano Brivio
2021-05-08 1:00 ` Stefano Brivio
2021-05-09 11:00 ` Arturo Borrero Gonzalez
2021-05-07 10:36 ` Stefano Brivio
2021-05-07 11:12 ` Arturo Borrero Gonzalez
2021-05-08 1:00 ` Stefano Brivio [this message]
2021-05-09 10:58 ` Arturo Borrero Gonzalez
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=20210508030046.4ae872f6@redhat.com \
--to=sbrivio@redhat.com \
--cc=arturo@netfilter.org \
--cc=netfilter-devel@vger.kernel.org \
/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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.