Note: This bug is displayed in read-only format because
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SanityOnly Verification:
[ralongi@ralongi openvswitch]$ rhpkg switch-branch fast-datapath-rhel-7
Branch fast-datapath-rhel-7 set up to track remote branch fast-datapath-rhel-7 from origin.
[ralongi@ralongi openvswitch]$ git log --oneline --grep=1643071
ba0148b Rebase to openvswitch-2.9.0-81.el7fdn
....
commit 4fe6a4014fc6aa0b18203909657afa5ca0ed120c
Author: Timothy Redaelli <tredaelli>
Date: Tue Nov 6 17:03:48 2018 +0100
Backport "ofproto-dpif-xlate: Avoid deadlock on multicast snooping recursion"
Resolves: #1643071
....
[ralongi@ralongi openvswitch]$ git show 80be318 | grep snoop
fatal: ambiguous argument '80be318': unknown revision or path not in the working tree.
Use '--' to separate paths from revisions, like this:
'git <command> [<revision>...] -- [<file>...]'
[ralongi@ralongi openvswitch]$ git show ba0148b | grep snoop
Backport "ofproto-dpif-xlate: Avoid deadlock on multicast snooping recursion"
diff --git a/0001-ofproto-dpif-xlate-Avoid-deadlock-on-multicast-snoop.patch b/0001-ofproto-dpif-xlate-Avoid-deadlock-on-multicast-snoop.patch
+++ b/0001-ofproto-dpif-xlate-Avoid-deadlock-on-multicast-snoop.patch
+Subject: [PATCH] ofproto-dpif-xlate: Avoid deadlock on multicast snooping
+Until now, OVS did multicast snooping outputs holding the read-lock on
+the mcast_snooping object. This could recurse via a patch port to try to
+It would probably be better to use RCU for mcast_snooping. That would be
+@@ -2554,6 +2556,53 @@ update_mcast_snooping_table(const struct xlate_ctx *ctx,
++ * mcast_snooping's rwlock for reading to iterate through the port lists and
++ * same mcast_snooping and attempt to take the write lock (see
+ struct mcast_snooping *ms OVS_UNUSED,
+ struct mcast_snooping *ms,
+ struct mcast_snooping *ms,
+ struct mcast_snooping *ms,
+ if (mcast_snooping_is_membership(flow->tp_src)) {
+ /* RFC4541: section 2.1.1, item 1: A snooping switch should
+ grp = mcast_snooping_lookup4(ms, flow->nw_dst, vlan);
+ grp = mcast_snooping_lookup(ms, &flow->ipv6_dst, vlan);
+ if (mcast_snooping_flood_unreg(ms)) {
+Patch330: 0001-ofproto-dpif-xlate-Avoid-deadlock-on-multicast-snoop.patch
+- Backport "ofproto-dpif-xlate: Avoid deadlock on multicast snooping recursion" (#1643071)
Regression test job link: https://beaker.engineering.redhat.com/jobs/3119374
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-2019:0014