This is a note to let you know that I've just added the patch titled
selftests: forwarding: Fix race condition in mirror installation
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
selftests-forwarding-fix-race-condition-in-mirror-installation.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From edcbf5137f093b5502f5f6b97cce3cbadbde27aa Mon Sep 17 00:00:00 2001
From: Danielle Ratson <danieller@xxxxxxxxxx>
Date: Thu, 25 Feb 2021 18:57:19 +0200
Subject: selftests: forwarding: Fix race condition in mirror installation
From: Danielle Ratson <danieller@xxxxxxxxxx>
commit edcbf5137f093b5502f5f6b97cce3cbadbde27aa upstream.
When mirroring to a gretap in hardware the device expects to be
programmed with the egress port and all the encapsulating headers. This
requires the driver to resolve the path the packet will take in the
software data path and program the device accordingly.
If the path cannot be resolved (in this case because of an unresolved
neighbor), then mirror installation fails until the path is resolved.
This results in a race that causes the test to sometimes fail.
Fix this by setting the neighbor's state to permanent, so that it is
always valid.
Fixes: b5b029399fa6d ("selftests: forwarding: mirror_gre_bridge_1d_vlan: Add STP test")
Signed-off-by: Danielle Ratson <danieller@xxxxxxxxxx>
Reviewed-by: Petr Machata <petrm@xxxxxxxxxx>
Signed-off-by: Ido Schimmel <idosch@xxxxxxxxxx>
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
tools/testing/selftests/net/forwarding/mirror_gre_bridge_1d_vlan.sh | 9 +++++++++
1 file changed, 9 insertions(+)
--- a/tools/testing/selftests/net/forwarding/mirror_gre_bridge_1d_vlan.sh
+++ b/tools/testing/selftests/net/forwarding/mirror_gre_bridge_1d_vlan.sh
@@ -86,11 +86,20 @@ test_ip6gretap()
test_gretap_stp()
{
+ # Sometimes after mirror installation, the neighbor's state is not valid.
+ # The reason is that there is no SW datapath activity related to the
+ # neighbor for the remote GRE address. Therefore whether the corresponding
+ # neighbor will be valid is a matter of luck, and the test is thus racy.
+ # Set the neighbor's state to permanent, so it would be always valid.
+ ip neigh replace 192.0.2.130 lladdr $(mac_get $h3) \
+ nud permanent dev br2
full_test_span_gre_stp gt4 $swp3.555 "mirror to gretap"
}
test_ip6gretap_stp()
{
+ ip neigh replace 2001:db8:2::2 lladdr $(mac_get $h3) \
+ nud permanent dev br2
full_test_span_gre_stp gt6 $swp3.555 "mirror to ip6gretap"
}
Patches currently in stable-queue which might be from danieller@xxxxxxxxxx are
queue-5.4/selftests-forwarding-fix-race-condition-in-mirror-installation.patch
