dpif-netdev: Don't use zero flow mark.

Zero flow mark is used to indicate the HW to remove the mark. A packet
marked with zero mark is received in SW without a mark at all, so it
cannot be used as a valid mark. Change the pool range to fix it.

Fixes: 241bad1 ("dpif-netdev: associate flow with a mark id")
Signed-off-by: Eli Britstein <elibr@mellanox.com>
Reviewed-by: Roni Bar Yanai <roniba@mellanox.com>
Acked-by: Sriharsha Basavapatna <sriharsha.basavapatna@broadcom.com>
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>

lib/dpif-netdev.c

@@ -2149,7 +2149,11 @@ dp_netdev_pmd_find_dpcls(struct dp_netdev_pmd_thread *pmd,
 }
 
 #define MAX_FLOW_MARK       (UINT32_MAX - 1)
-#define INVALID_FLOW_MARK   (UINT32_MAX)
+#define INVALID_FLOW_MARK   0
+/* Zero flow mark is used to indicate the HW to remove the mark. A packet
+ * marked with zero mark is received in SW without a mark at all, so it
+ * cannot be used as a valid mark.
+ */
 
 struct megaflow_to_mark_data {
     const struct cmap_node node;
@@ -2175,7 +2179,7 @@ flow_mark_alloc(void)
 
     if (!flow_mark.pool) {
         /* Haven't initiated yet, do it here */
-        flow_mark.pool = id_pool_create(0, MAX_FLOW_MARK);
+        flow_mark.pool = id_pool_create(1, MAX_FLOW_MARK);
     }
 
     if (id_pool_alloc_id(flow_mark.pool, &mark)) {

tests/dpif-netdev.at

@@ -393,7 +393,7 @@ skb_priority(0),skb_mark(0),ct_state(0),ct_zone(0),ct_mark(0),ct_label(0),recirc
    # Check that flow successfully offloaded.
    OVS_WAIT_UNTIL([grep "succeed to add netdev flow" ovs-vswitchd.log])
    AT_CHECK([filter_hw_flow_install < ovs-vswitchd.log | strip_xout], [0], [dnl
-p1: flow put[[create]]: flow match: recirc_id=0,eth,ip,in_port=1,vlan_tci=0x0000,nw_frag=no, mark: 0
+p1: flow put[[create]]: flow match: recirc_id=0,eth,ip,in_port=1,vlan_tci=0x0000,nw_frag=no, mark: 1
 ])
    # Check that datapath flow installed successfully.
    AT_CHECK([filter_flow_install < ovs-vswitchd.log | strip_xout], [0], [dnl
@@ -404,7 +404,7 @@ recirc_id(0),in_port(1),packet_type(ns=0,id=0),eth_type(0x0800),ipv4(frag=no), a
 
    # Check for succesfull packet matching with installed offloaded flow.
    AT_CHECK([filter_hw_packet_netdev_dummy < ovs-vswitchd.log | strip_xout], [0], [dnl
-p1: packet: ip,vlan_tci=0x0000,dl_src=00:06:07:08:09:0a,dl_dst=00:01:02:03:04:05,nw_src=127.0.0.1,nw_dst=127.0.0.1,nw_proto=0,nw_tos=0,nw_ecn=0,nw_ttl=64 matches with flow: recirc_id=0,eth,ip,vlan_tci=0x0000,nw_frag=no with mark: 0
+p1: packet: ip,vlan_tci=0x0000,dl_src=00:06:07:08:09:0a,dl_dst=00:01:02:03:04:05,nw_src=127.0.0.1,nw_dst=127.0.0.1,nw_proto=0,nw_tos=0,nw_ecn=0,nw_ttl=64 matches with flow: recirc_id=0,eth,ip,vlan_tci=0x0000,nw_frag=no with mark: 1
 ])
 
    ovs-appctl revalidator/wait
@@ -421,7 +421,7 @@ recirc_id(0),in_port(1),packet_type(ns=0,id=0),eth_type(0x0800),ipv4(frag=no), p
    # Check that flow successfully deleted from HW.
    OVS_WAIT_UNTIL([grep "succeed to delete netdev flow" ovs-vswitchd.log])
    AT_CHECK([filter_hw_flow_del < ovs-vswitchd.log | strip_xout], [0], [dnl
-p1: flow del: mark: 0
+p1: flow del: mark: 1
 ])
    OVS_VSWITCHD_STOP
    AT_CLEANUP])
@@ -460,7 +460,7 @@ packet_type(ns=0,id=0),eth(src=00:06:07:08:09:0a,dst=00:01:02:03:04:05),eth_type
    # Check that flow successfully offloaded.
    OVS_WAIT_UNTIL([grep "succeed to add netdev flow" ovs-vswitchd.log])
    AT_CHECK([filter_hw_flow_install < ovs-vswitchd.log | strip_xout], [0], [dnl
-p1: flow put[[create]]: flow match: recirc_id=0,eth,udp,in_port=1,dl_vlan=99,dl_vlan_pcp=7,nw_src=127.0.0.1,nw_frag=no,tp_dst=82, mark: 0
+p1: flow put[[create]]: flow match: recirc_id=0,eth,udp,in_port=1,dl_vlan=99,dl_vlan_pcp=7,nw_src=127.0.0.1,nw_frag=no,tp_dst=82, mark: 1
 ])
    # Check that datapath flow installed successfully.
    AT_CHECK([filter_flow_install < ovs-vswitchd.log | strip_xout], [0], [dnl
@@ -472,7 +472,7 @@ recirc_id(0),in_port(1),packet_type(ns=0,id=0),eth_type(0x8100),vlan(vid=99,pcp=
    # Check for succesfull packet matching with installed offloaded flow.
    AT_CHECK([filter_hw_packet_netdev_dummy < ovs-vswitchd.log | strip_xout], [0], [dnl
 p1: packet: udp,dl_vlan=99,dl_vlan_pcp=7,vlan_tci1=0x0000,dl_src=00:06:07:08:09:0a,dl_dst=00:01:02:03:04:05,nw_src=127.0.0.1,nw_dst=127.0.0.1,nw_tos=0,nw_ecn=0,nw_ttl=64,tp_src=81,tp_dst=82 dnl
-matches with flow: recirc_id=0,eth,udp,dl_vlan=99,dl_vlan_pcp=7,nw_src=127.0.0.1,nw_frag=no,tp_dst=82 with mark: 0
+matches with flow: recirc_id=0,eth,udp,dl_vlan=99,dl_vlan_pcp=7,nw_src=127.0.0.1,nw_frag=no,tp_dst=82 with mark: 1
 ])
 
    ovs-appctl revalidator/wait
@@ -490,7 +490,7 @@ packets:1, bytes:64, used:0.0s, actions:set(ipv4(src=192.168.0.7)),set(udp(dst=3
    # Check that flow successfully deleted from HW.
    OVS_WAIT_UNTIL([grep "succeed to delete netdev flow" ovs-vswitchd.log])
    AT_CHECK([filter_hw_flow_del < ovs-vswitchd.log | strip_xout], [0], [dnl
-p1: flow del: mark: 0
+p1: flow del: mark: 1
 ])
 
    # Check that ip address and udp port were correctly modified in output packets.