[SRU][Cosmic][Bionic][PATCH 0/6] Fixes for LP1797367
frank.heimes at canonical.com
Wed Nov 7 18:20:40 UTC 2018
== SRU Justification ==
While running a series of stress tests for network on a bond device on
Ubuntu 18.04.1 with kernel 4.15.0-36.39,
kernel panic is observed (btw. also on non-bond devices).
This looks like a race between disabling a qeth device and accessing debugfs.
This is critical and leads repeatedly to a crash (sooner or later).
== Fix ==
e19e5be8b4ca ("s390/qeth: sanitize strings in debug messages")
750b162 ("s390/qeth: reduce hard-coded access to ccw channels")
d857e11 ("s390/qeth: remove outdated portname debug msg")
9d0a58f ("s390/qeth: avoid using is_multicast_ether_addr_64bits on (u8 *)")
8174aa8 ("s390/qeth: consolidate qeth MAC address helpers")
4641b02 ("s390/qeth: don't keep track of MAC address's cast type")
== Regression Potential ==
- limited to s390x
- and furthermore limited to qeth driver
- patches a problem identified during testing
- fix was tested by IBM before submitted
== Test Case ==
var=$((var + 1))
echo "DBG count is $var"
dbginfo.sh -d /tmp/DBGINFO
rm -rf /tmp/DBGINFO*
echo "chzdev now is $var"
chzdev -e <qeth device>
chzdev -d <qeth device>
and in avg. in less than 20 cycles a crash happens (usually < 10).
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