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Vladimir Oltean f9674c52a1 net: mscc: ocelot: fix VCAP IS2 filters matching on both lookups
[ Upstream commit 6741e11880 ]

The VCAP IS2 TCAM is looked up twice per packet, and each filter can be
configured to only match during the first, second lookup, or both, or
none.

The blamed commit wrote the code for making VCAP IS2 filters match only
on the given lookup. But right below that code, there was another line
that explicitly made the lookup a "don't care", and this is overwriting
the lookup we've selected. So the code had no effect.

Some of the more noticeable effects of having filters match on both
lookups:

- in "tc -s filter show dev swp0 ingress", we see each packet matching a
  VCAP IS2 filter counted twice. This throws off scripts such as
  tools/testing/selftests/net/forwarding/tc_actions.sh and makes them
  fail.

- a "tc-drop" action offloaded to VCAP IS2 needs a policer as well,
  because once the CPU port becomes a member of the destination port
  mask of a packet, nothing removes it, not even a PERMIT/DENY mask mode
  with a port mask of 0. But VCAP IS2 rules with the POLICE_ENA bit in
  the action vector can only appear in the first lookup. What happens
  when a filter matches both lookups is that the action vector is
  combined, and this makes the POLICE_ENA bit ineffective, since the
  last lookup in which it has appeared is the second one. In other
  words, "tc-drop" actions do not drop packets for the CPU port, dropped
  packets are still seen by software unless there was an FDB entry that
  directed those packets to some other place different from the CPU.

The last bit used to work, because in the initial commit b596229448
("net: mscc: ocelot: Add support for tcam"), we were writing the FIRST
field of the VCAP IS2 half key with a 1, not with a "don't care".
The change to "don't care" was made inadvertently by me in commit
c1c3993edb ("net: mscc: ocelot: generalize existing code for VCAP"),
which I just realized, and which needs a separate fix from this one,
for "stable" kernels that lack the commit blamed below.

Fixes: 226e9cd82a ("net: mscc: ocelot: only install TCAM entries into a specific lookup and PAG")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-05-18 10:23:42 +02:00
arch arm: remove CONFIG_ARCH_HAS_HOLES_MEMORYMODEL 2022-05-15 20:00:09 +02:00
block block-map: add __GFP_ZERO flag for alloc_page in function bio_copy_kern 2022-05-12 12:25:45 +02:00
certs certs: Trigger creation of RSA module signing key if it's not an RSA key 2021-09-15 09:50:29 +02:00
crypto crypto: authenc - Fix sleep in atomic context in decrypt_tail 2022-04-08 14:39:59 +02:00
Documentation arm: remove CONFIG_ARCH_HAS_HOLES_MEMORYMODEL 2022-05-15 20:00:09 +02:00
drivers net: mscc: ocelot: fix VCAP IS2 filters matching on both lookups 2022-05-18 10:23:42 +02:00
fs arm: remove CONFIG_ARCH_HAS_HOLES_MEMORYMODEL 2022-05-15 20:00:09 +02:00
include net: Fix features skip in for_each_netdev_feature() 2022-05-18 10:23:42 +02:00
init init/main.c: return 1 from handled __setup() functions 2022-04-13 21:01:01 +02:00
ipc shm: extend forced shm destroy to support objects from several IPC nses 2021-12-01 09:19:10 +01:00
kernel rcu: Apply callbacks processing time limit only on softirq 2022-05-12 12:25:45 +02:00
lib hex2bin: fix access beyond string end 2022-05-09 09:04:59 +02:00
LICENSES LICENSES/deprecated: add Zlib license text 2020-09-16 14:33:49 +02:00
mm mm: userfaultfd: fix missing cache flush in mcopy_atomic_pte() and __mcopy_atomic() 2022-05-15 20:00:09 +02:00
net mac80211: Reset MBSSID parameters upon connection 2022-05-18 10:23:42 +02:00
samples samples/bpf, xdpsock: Fix race when running for fix duration of time 2022-04-08 14:40:21 +02:00
scripts gcc-plugins: latent_entropy: use /dev/urandom 2022-04-20 09:23:26 +02:00
security Fix incorrect type in assignment of ipv6 port for audit 2022-04-08 14:40:31 +02:00
sound ASoC: dmaengine: Restore NULL prepare_slave_config() callback 2022-05-12 12:25:37 +02:00
tools selftests: ocelot: tc_flower_chains: specify conform-exceed action for policer 2022-05-12 12:25:42 +02:00
usr usr/include/Makefile: add linux/nfc.h to the compile-test coverage 2022-02-01 17:25:48 +01:00
virt KVM: Prevent module exit until all VMs are freed 2022-04-08 14:40:38 +02:00
.clang-format RDMA 5.10 pull request 2020-10-17 11:18:18 -07:00
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore kbuild: generate Module.symvers only when vmlinux exists 2021-05-19 10:12:59 +02:00
.mailmap mailmap: add two more addresses of Uwe Kleine-König 2020-12-06 10:19:07 -08:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Move Jason Cooper to CREDITS 2020-11-30 10:20:34 +01:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS MAINTAINERS: adjust GCC PLUGINS after gcc-plugin.sh removal 2021-12-14 11:32:46 +01:00
Makefile Linux 5.10.116 2022-05-15 20:00:09 +02:00
README

Linux kernel
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