Bug 1986445

This is due to a change in %{_libdir} directory from /usr/lib to /usr/lib64. It can be addressed setting the TC_LIB_DIR environment variable to /usr/lib64/tc.
Mingyu, can you please consider to set itm and qa_ack+ on this? I can make sure this environment variable is set at iproute-tc install-time.

Verified the case pass with  RHEL-8.6.0-20210817.1( iproute-tc-5.12.0-3.el8.x86_64 and kernel-4.18.0-331.el8)

test case: /kernel/networking/tcp/bugs/epoll_write_event_missing_bz1386136 
beaker job: https://beaker.engineering.redhat.com/recipes/10516541#task130671830

: [ 03:20:05 ] :: [  BEGIN   ] :: Running 'dnf install -y iproute-tc'
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Last metadata expiration check: 0:10:13 ago on Thu 19 Aug 2021 03:09:52 AM EDT.
Package iproute-tc-5.12.0-3.el8.x86_64 is already installed.
Dependencies resolved.
Nothing to do.
Complete!
:: [ 03:20:06 ] :: [   PASS   ] :: Command 'dnf install -y iproute-tc' (Expected 0, got 0)
:: [ 03:20:06 ] :: [  BEGIN   ] :: Running 'tc qdisc add dev ens5f0 root handle 1:0 prio'
:: [ 03:20:06 ] :: [   PASS   ] :: Command 'tc qdisc add dev ens5f0 root handle 1:0 prio' (Expected 0, got 0)
:: [ 03:20:06 ] :: [  BEGIN   ] :: Running 'tc qdisc add dev ens5f0 parent 1:3 handle 30: netem delay 10ms 5ms distribution normal'
:: [ 03:20:06 ] :: [   PASS   ] :: Command 'tc qdisc add dev ens5f0 parent 1:3 handle 30: netem delay 10ms 5ms distribution normal' (Expected 0, got 0)
:: [ 03:20:06 ] :: [  BEGIN   ] :: Running 'tc filter add dev ens5f0 protocol ip parent 1:0 prio 3 u32 match ip dst 192.168.1.20/32 flowid 1:3'
:: [ 03:20:06 ] :: [   PASS   ] :: Command 'tc filter add dev ens5f0 protocol ip parent 1:0 prio 3 u32 match ip dst 192.168.1.20/32 flowid 1:3' (Expected 0, got 0)
:: [ 03:20:06 ] :: [  BEGIN   ] :: Running 'tc qdisc show dev ens5f0'
qdisc prio 1: root refcnt 8 bands 3 priomap 1 2 2 2 1 2 0 0 1 1 1 1 1 1 1 1
qdisc netem 30: parent 1:3 limit 1000 delay 10ms  5ms
:: [ 03:20:06 ] :: [   PASS   ] :: Command 'tc qdisc show dev ens5f0' (Expected 0, got 0)
:: [ 03:20:06 ] :: [  BEGIN   ] :: Running 'tc filter show dev ens5f0'
filter parent 1: protocol ip pref 3 u32 chain 0 
filter parent 1: protocol ip pref 3 u32 chain 0 fh 800: ht divisor 1 
filter parent 1: protocol ip pref 3 u32 chain 0 fh 800::800 order 2048 key ht 800 bkt 0 flowid 1:3 not_in_hw 
  match c0a80114/ffffffff at 16
:: [ 03:20:06 ] :: [   PASS   ] :: Command 'tc filter show dev ens5f0' (Expected 0, got 0)

Hi Andrea,
 The case fail again on the latest Distro, RHEL-8.6.0-20210902.0(iproute-tc-5.12.0-3.el8.x86_64 and kernel-4.18.0-339.el8)
 Run the commands, fail only at the first time, and then run them again, pass.
 Could you help check?

beaker job:
https://beaker.engineering.redhat.com/recipes/10638318#task131872728,task131872729

 Thanks
Xiumei Mu

Hi Xiumei, I suspect this is due to the fact that iproute-tc is installed just before the test.
Can you please try to execute "export TC_LIB_DIR=/usr/lib64/tc" before the first test and see if it passes, too?

(In reply to Andrea Claudi from comment #7)
> Hi Xiumei, I suspect this is due to the fact that iproute-tc is installed
> just before the test.
> Can you please try to execute "export TC_LIB_DIR=/usr/lib64/tc" before the
> first test and see if it passes, too?

Andrea,
 sorry for the late reply, your workaround works. Thanks.

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 (iproute bug fix and enhancement update), 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-2021:4389