DPDK patches and discussions
 help / color / mirror / Atom feed
From: Stephen Hemminger <stephen@networkplumber.org>
To: Dariusz Sosnowski <dsosnowski@nvidia.com>
Cc: Khadem Ullah <14pwcse1224@uetpeshawar.edu.pk>,
	Thomas Monjalon <thomas@monjalon.net>,
	Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>, <dev@dpdk.org>,
	<rasland@nvidia.com>, <stable@dpdk.org>,
	"Viacheslav Ovsiienko" <viacheslavo@nvidia.com>,
	Bing Zhao <bingz@nvidia.com>, Ori Kam <orika@nvidia.com>,
	Suanming Mou <suanmingm@nvidia.com>,
	Matan Azrad <matan@nvidia.com>
Subject: Re: [PATCH] net/mlx5: fix crash when secondary queries dev info after primary exits
Date: Mon, 21 Jul 2025 07:50:28 -0700	[thread overview]
Message-ID: <20250721075028.77fddec0@hermes.local> (raw)
In-Reply-To: <20250721105819.2ci66fl7bzikwb22@ds-vm-debian.local>

On Mon, 21 Jul 2025 12:58:19 +0200
Dariusz Sosnowski <dsosnowski@nvidia.com> wrote:

> I don't think it's an issue on PMD level, but rather on
> ethdev/multi-process handling level.
> 
> When primary process closes the port, ethdev library zeroes and frees
> device data shared between processes.
> ethdev port data (rte_eth_dev) on secondary is not updated so it now points to
> invalid data. rte_eth_dev_info_get() is not the only API call affected.
> 
> If the primary process closes the port before exiting
> (like testpmd does) and it exits before the secondary,
> the any driver call seems invalid because of that use-after-free behavior.
> 
> @Thomas, @Andrew - Do you happen to know if doing anything on ethdev ports
> in secondary process after primary has gracefully exited is supported?


No this is not supported.
A properly written secondary process monitors to see when primary exits.
There are many other parts of DPDK that assume primary is always available.

      parent reply	other threads:[~2025-07-21 14:50 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-07-21  7:38 Khadem Ullah
2025-07-21 10:58 ` Dariusz Sosnowski
2025-07-21 11:38   ` [PATCH] net/mlx5: fix crash when using meter in transfer flow Khadem Ullah
2025-07-21 11:46   ` [PATCH] net/mlx5: fix crash when secondary queries dev info after primary exits Ivan Malov
2025-07-21 11:59     ` Thomas Monjalon
2025-07-21 14:01       ` Dariusz Sosnowski
2025-07-21 14:50   ` Stephen Hemminger [this message]

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=20250721075028.77fddec0@hermes.local \
    --to=stephen@networkplumber.org \
    --cc=14pwcse1224@uetpeshawar.edu.pk \
    --cc=andrew.rybchenko@oktetlabs.ru \
    --cc=bingz@nvidia.com \
    --cc=dev@dpdk.org \
    --cc=dsosnowski@nvidia.com \
    --cc=matan@nvidia.com \
    --cc=orika@nvidia.com \
    --cc=rasland@nvidia.com \
    --cc=stable@dpdk.org \
    --cc=suanmingm@nvidia.com \
    --cc=thomas@monjalon.net \
    --cc=viacheslavo@nvidia.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).