selftests: drv: net: fix test failure on ipv6 sys

The `get_interface_info` call has ip version hard-coded which leads to
failures on an IPV6 system. The NetDrvEnv class already gathers
information about remote interface, so instead of fixing the local
implementation switch to using cfg.remote_ifname.

Before:
./drivers/net/ping.py
Traceback (most recent call last):
  File "/new_tests/./drivers/net/ping.py", line 217, in <module>
    main()
  File "/new_tests/./drivers/net/ping.py", line 204, in main
    get_interface_info(cfg)
  File "/new_tests/./drivers/net/ping.py", line 128, in get_interface_info
    raise KsftFailEx('Can not get remote interface')
net.lib.py.ksft.KsftFailEx: Can not get remote interface

After:
./drivers/net/ping.py
TAP version 13
1..6
ok 1 ping.test_default # SKIP Test requires IPv4 connectivity
ok 2 ping.test_xdp_generic_sb # SKIP Test requires IPv4 connectivity
ok 3 ping.test_xdp_generic_mb # SKIP Test requires IPv4 connectivity
ok 4 ping.test_xdp_native_sb # SKIP Test requires IPv4 connectivity
ok 5 ping.test_xdp_native_mb # SKIP Test requires IPv4 connectivity
ok 6 ping.test_xdp_offload # SKIP device does not support offloaded XDP
Totals: pass:0 fail:0 xfail:0 xpass:0 skip:6 error:0

Fixes: 75cc19c8ff89 ("selftests: drv-net: add xdp cases for ping.py")
Signed-off-by: Mohsin Bashir <mohsin.bashr@gmail.com>
Reviewed-by: David Wei <dw@davidwei.uk>
Link: https://patch.msgid.link/20250503013518.1722913-2-mohsin.bashr@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 9 insertions, 13 deletions

diff --git a/tools/testing/selftests/drivers/net/ping.py b/tools/testing/selftests/drivers/net/ping.py
index 4b6822866066..5272e8b3536d 100755
--- a/tools/testing/selftests/drivers/net/ping.py
+++ b/tools/testing/selftests/drivers/net/ping.py
@@ -9,7 +9,6 @@ from lib.py import EthtoolFamily, NetDrvEpEnv
 from lib.py import bkg, cmd, wait_port_listen, rand_port
 from lib.py import defer, ethtool, ip
 
-remote_ifname=""
 no_sleep=False
 
 def _test_v4(cfg) -> None:
@@ -57,7 +56,7 @@ def _set_offload_checksum(cfg, netnl, on) -> None:
 
 def _set_xdp_generic_sb_on(cfg) -> None:
     prog = cfg.net_lib_dir / "xdp_dummy.bpf.o"
-    cmd(f"ip link set dev {remote_ifname} mtu 1500", shell=True, host=cfg.remote)
+    cmd(f"ip link set dev {cfg.remote_ifname} mtu 1500", shell=True, host=cfg.remote)
     cmd(f"ip link set dev {cfg.ifname} mtu 1500 xdpgeneric obj {prog} sec xdp", shell=True)
     defer(cmd, f"ip link set dev {cfg.ifname} xdpgeneric off")
 
@@ -66,8 +65,8 @@ def _set_xdp_generic_sb_on(cfg) -> None:
 
 def _set_xdp_generic_mb_on(cfg) -> None:
     prog = cfg.net_lib_dir / "xdp_dummy.bpf.o"
-    cmd(f"ip link set dev {remote_ifname} mtu 9000", shell=True, host=cfg.remote)
-    defer(ip, f"link set dev {remote_ifname} mtu 1500", host=cfg.remote)
+    cmd(f"ip link set dev {cfg.remote_ifname} mtu 9000", shell=True, host=cfg.remote)
+    defer(ip, f"link set dev {cfg.remote_ifname} mtu 1500", host=cfg.remote)
     ip("link set dev %s mtu 9000 xdpgeneric obj %s sec xdp.frags" % (cfg.ifname, prog))
     defer(ip, f"link set dev {cfg.ifname} mtu 1500 xdpgeneric off")
 
@@ -76,7 +75,7 @@ def _set_xdp_generic_mb_on(cfg) -> None:
 
 def _set_xdp_native_sb_on(cfg) -> None:
     prog = cfg.net_lib_dir / "xdp_dummy.bpf.o"
-    cmd(f"ip link set dev {remote_ifname} mtu 1500", shell=True, host=cfg.remote)
+    cmd(f"ip link set dev {cfg.remote_ifname} mtu 1500", shell=True, host=cfg.remote)
     cmd(f"ip -j link set dev {cfg.ifname} mtu 1500 xdp obj {prog} sec xdp", shell=True)
     defer(ip, f"link set dev {cfg.ifname} mtu 1500 xdp off")
     xdp_info = ip("-d link show %s" % (cfg.ifname), json=True)[0]
@@ -93,8 +92,8 @@ def _set_xdp_native_sb_on(cfg) -> None:
 
 def _set_xdp_native_mb_on(cfg) -> None:
     prog = cfg.net_lib_dir / "xdp_dummy.bpf.o"
-    cmd(f"ip link set dev {remote_ifname} mtu 9000", shell=True, host=cfg.remote)
-    defer(ip, f"link set dev {remote_ifname} mtu 1500", host=cfg.remote)
+    cmd(f"ip link set dev {cfg.remote_ifname} mtu 9000", shell=True, host=cfg.remote)
+    defer(ip, f"link set dev {cfg.remote_ifname} mtu 1500", host=cfg.remote)
     try:
         cmd(f"ip link set dev {cfg.ifname} mtu 9000 xdp obj {prog} sec xdp.frags", shell=True)
         defer(ip, f"link set dev {cfg.ifname} mtu 1500 xdp off")
@@ -112,18 +111,15 @@ def _set_xdp_offload_on(cfg) -> None:
     except Exception as e:
         raise KsftSkipEx('device does not support offloaded XDP')
     defer(ip, f"link set dev {cfg.ifname} xdpoffload off")
-    cmd(f"ip link set dev {remote_ifname} mtu 1500", shell=True, host=cfg.remote)
+    cmd(f"ip link set dev {cfg.remote_ifname} mtu 1500", shell=True, host=cfg.remote)
 
     if no_sleep != True:
         time.sleep(10)
 
 def get_interface_info(cfg) -> None:
-    global remote_ifname
     global no_sleep
 
-    remote_info = cmd(f"ip -4 -o addr show to {cfg.remote_addr_v['4']} | awk '{{print $2}}'", shell=True, host=cfg.remote).stdout
-    remote_ifname = remote_info.rstrip('\n')
-    if remote_ifname == "":
+    if cfg.remote_ifname == "":
         raise KsftFailEx('Can not get remote interface')
     local_info = ip("-d link show %s" % (cfg.ifname), json=True)[0]
     if 'parentbus' in local_info and local_info['parentbus'] == "netdevsim":
@@ -136,7 +132,7 @@ def set_interface_init(cfg) -> None:
     cmd(f"ip link set dev {cfg.ifname} xdp off ", shell=True)
     cmd(f"ip link set dev {cfg.ifname} xdpgeneric off ", shell=True)
     cmd(f"ip link set dev {cfg.ifname} xdpoffload off", shell=True)
-    cmd(f"ip link set dev {remote_ifname} mtu 1500", shell=True, host=cfg.remote)
+    cmd(f"ip link set dev {cfg.remote_ifname} mtu 1500", shell=True, host=cfg.remote)
 
 def test_default(cfg, netnl) -> None:
     _set_offload_checksum(cfg, netnl, "off")