From: Ami Sabo <AmiS@Radware.com>
To: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Cc: "dev@dpdk.org" <dev@dpdk.org>, "stable@dpdk.org" <stable@dpdk.org>
Subject: Re: [dpdk-stable] [PATCH 2/2] net/virtio-user: fix multi-process issue
Date: Tue, 28 Feb 2017 07:50:47 +0000 [thread overview]
Message-ID: <25F949B549CFD14EABC392C69312415C0106DC094F@ILMB2.corp.radware.com> (raw)
In-Reply-To: <20170228064016.GL18844@yliu-dev.sh.intel.com>
Hi,
You are right, the commit I mentioned didn't cause the issue - it just flooded it.
The real issue is that rte_eth_dev_allocate should be called only from the primary process.
Tomas's commit flood the issue by resseting rte_eth_dev_data, so now, when the virtio-user secondary process comes up and calls rte_eth_dev_allocate
It clears the ethdev->data struct (so fields like rx_queues, mac_addrs, etc will be 0, plus this may cause race condition between the primary and secondary processes...)
--ami
-----Original Message-----
From: Yuanhan Liu [mailto:yuanhan.liu@linux.intel.com]
Sent: Tuesday, February 28, 2017 8:40 AM
To: Ami Sabo
Cc: dev@dpdk.org; stable@dpdk.org
Subject: Re: [PATCH 2/2] net/virtio-user: fix multi-process issue
On Sun, Feb 26, 2017 at 11:55:26AM +0200, Ami Sabo wrote:
> Secondary process doesn't properly attach to the rte_eth_device
> initialized by the primary process.
>
> ccessing device from secondary process (e.g. via rte_eth_rx_burst),
> causes process to crash. because rte_eth_dev_data is not properly set.
>
> The issue was flood by
> 'commit 7f95f78a8aea ("ethdev: clear data when allocating device")'
> which now clears rte_eth_dev_data entry.
> For pci devices the struct is initialized by rte_eth_dev_pci_probe
> ->eth_dev_attach_secondary().
> However, for virtio-user virtio_user_pmd_probe() is called instead of
> rte_eth_dev_pci_probe().
>
> The fix is to call rte_eth_dev_attach_secondary(), for secondary
> process, from virtio_user_pmd_probe.
>
> Fixes: 7f95f78a8aea ("ethdev: clear data when allocating device")
Are you sure that's the real culprit? As I'm aware of, virtio-user is not built with multiple process support in the beginning. That said, it's likely that the first commit introduces virtio-user is the "culprit" commit.
Besides that, the code looks good to me. If Thomas is fine with your first patch, I could merge them to my tree.
--yliu
prev parent reply other threads:[~2017-02-28 7:50 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <1487851096-32479-1-git-send-email-amis@radware.com>
2017-02-26 9:55 ` [dpdk-stable] [PATCH 0/2] Fix virtio-user multi-process crash Ami Sabo
2017-02-26 9:55 ` [dpdk-stable] [PATCH 1/2] lib/librte_ether: export secondary attach function Ami Sabo
2017-02-28 6:37 ` Yuanhan Liu
2017-03-02 7:51 ` [dpdk-stable] [PATCH v2 0/3] Fix virtio-user multi-process crash Ami Sabo
2017-03-02 7:51 ` [dpdk-stable] [PATCH v2 1/3] lib/librte_ether: export secondary attach function Ami Sabo
2017-03-02 7:51 ` [dpdk-stable] [PATCH v2 2/3] net/virtio-user: fix multi-process issue Ami Sabo
2017-03-02 7:51 ` [dpdk-stable] [PATCH v2 3/3] lib/librte_ether: fix code style issues Ami Sabo
2017-03-02 8:12 ` Yuanhan Liu
2017-03-02 9:00 ` [dpdk-stable] [PATCH 0/2] Fix virtio-user multi-process crash Ami Sabo
2017-03-02 9:00 ` [dpdk-stable] [PATCH 1/2] lib/librte_ether: export secondary attach function Ami Sabo
2017-03-02 9:00 ` [dpdk-stable] [PATCH 2/2] net/virtio-user: fix multi-process issue Ami Sabo
2017-04-14 12:13 ` [dpdk-stable] [PATCH 0/2] Fix virtio-user multi-process crash Thomas Monjalon
2017-02-26 9:55 ` [dpdk-stable] [PATCH 2/2] net/virtio-user: fix multi-process issue Ami Sabo
2017-02-28 6:40 ` Yuanhan Liu
2017-02-28 7:50 ` Ami Sabo [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=25F949B549CFD14EABC392C69312415C0106DC094F@ILMB2.corp.radware.com \
--to=amis@radware.com \
--cc=dev@dpdk.org \
--cc=stable@dpdk.org \
--cc=yuanhan.liu@linux.intel.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).