Bug 1575067

Summary: Backport "net/nfp: fix mbufs releasing when stop or close"
Product: Red Hat Enterprise Linux 7 Reporter: Timothy Redaelli <tredaelli>
Component: openvswitchAssignee: Timothy Redaelli <tredaelli>
Status: CLOSED ERRATA QA Contact: Jean-Tsung Hsiao <jhsiao>
Severity: medium Docs Contact:
Priority: medium    
Version: 7.6CC: atragler, ctrautma, jhsiao, ovs-team, pablo.cascon, pvauter, tredaelli
Target Milestone: rc   
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard:
Fixed In Version: openvswitch-2.9.0-30.el7fdn Doc Type: If docs needed, set a value
Doc Text:
Story Points: ---
Clone Of: 1573912 Environment:
Last Closed: 2018-06-21 13:36:35 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:

Description Timothy Redaelli 2018-05-04 16:46:54 UTC 
+++ This bug was initially created as a clone of Bug #1573912 +++

Would like to have the following DPDK commit in RHEL 7.6. Not sure how the process works for DPDK, feel free to educate me:

commit 0c0e46c36bcc5dfe9d2aa605e1a5f714d45e0b7f
Author: Alejandro Lucero <alejandro.lucero>
Date:   Mon Apr 23 12:23:58 2018 +0100

    net/nfp: fix mbufs releasing when stop or close
    
    PMDs have the responsibility of releasing mbufs sent through xmit burst
    function. NFP PMD attaches those sent mbufs to the TX ring structure,
    and it is at the next time a specific ring descriptor is going to be
    used when the previous linked mbuf, already transmitted at that point,
    is released. Those mbufs belonging to a chained mbuf got its own link
    to a ring descriptor, and they are released independently of the mbuf
    head of that chain.
    
    The problem is how those mbufs are released when the PMD is stopped or
    closed. Instead of releasing those mbufs as the xmit functions does,
    this is independently of being in a mbuf chain, the code calls
    rte_pktmbuf_free which will release not just the mbuf head in that
    chain but all the chained mbufs. The loop will try to release those
    mbufs which have already been released again when chained mbufs exist.
    
    This patch fixes the problem using rte_pktmbuf_free_seg instead.
    
    Fixes: b812daadad0d ("nfp: add Rx and Tx")
    Cc: stable
    
    Signed-off-by: Alejandro Lucero <alejandro.lucero>
Comment 7 Jean-Tsung Hsiao 2018-06-19 15:41:11 UTC 
The package has been verified by running concurrent netperf tests between guests over OVS-dpdk/vxlan/nfp tunnel.
Comment 9 Jean-Tsung Hsiao 2018-06-20 18:44:51 UTC 
NFP people has done their part. Please check
https://bugzilla.redhat.com/show_bug.cgi?id=1573912#c20
Comment 10 errata-xmlrpc 2018-06-21 13:36:35 UTC 
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHBA-2018:1962