diff mbox series

[net,5/6] net: mscc: ocelot: restrict tc-trap actions to VCAP IS2 lookup 0

Message ID 20220503115728.834457-6-vladimir.oltean@nxp.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series Ocelot VCAP fixes | expand

Checks

Context Check Description
netdev/tree_selection success Clearly marked for net
netdev/fixes_present success Fixes tag present in non-next series
netdev/subject_prefix success Link
netdev/cover_letter success Series has a cover letter
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 0 this patch: 0
netdev/cc_maintainers success CCed 10 of 10 maintainers
netdev/build_clang success Errors and warnings before: 0 this patch: 0
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/verify_fixes success Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 0 this patch: 0
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 12 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Vladimir Oltean May 3, 2022, 11:57 a.m. UTC
Once the CPU port was added to the destination port mask of a packet, it
can never be cleared, so even packets marked as dropped by the MASK_MODE
of a VCAP IS2 filter will still reach it. This is why we need the
OCELOT_POLICER_DISCARD to "kill dropped packets dead" and make software
stop seeing them.

We disallow policer rules from being put on any other chain than the one
for the first lookup, but we don't do this for "drop" rules, although we
should. This change is merely ascertaining that the rules dont't
(completely) work and letting the user know.

The blamed commit is the one that introduced the multi-chain architecture
in ocelot. Prior to that, we should have always offloaded the filters to
VCAP IS2 lookup 0, where they did work.

Fixes: 1397a2eb52e2 ("net: mscc: ocelot: create TCAM skeleton from tc filter chains")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
---
 drivers/net/ethernet/mscc/ocelot_flower.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/ethernet/mscc/ocelot_flower.c b/drivers/net/ethernet/mscc/ocelot_flower.c
index b8617e940063..e598308ef09d 100644
--- a/drivers/net/ethernet/mscc/ocelot_flower.c
+++ b/drivers/net/ethernet/mscc/ocelot_flower.c
@@ -280,9 +280,10 @@  static int ocelot_flower_parse_action(struct ocelot *ocelot, int port,
 			filter->type = OCELOT_VCAP_FILTER_OFFLOAD;
 			break;
 		case FLOW_ACTION_TRAP:
-			if (filter->block_id != VCAP_IS2) {
+			if (filter->block_id != VCAP_IS2 ||
+			    filter->lookup != 0) {
 				NL_SET_ERR_MSG_MOD(extack,
-						   "Trap action can only be offloaded to VCAP IS2");
+						   "Trap action can only be offloaded to VCAP IS2 lookup 0");
 				return -EOPNOTSUPP;
 			}
 			if (filter->goto_target != -1) {