The TSO test wants to make sure that there isn't a lot of retransmits,
because that could indicate that device has a buggy TSO implementation.
On debug kernels, however, we're likely to see significant packet loss
because we simply overwhelm the receiver.
In a QEMU loop with virtio devices we see ~10% false positive rate
with occasional run hitting the threshold of 25% packet loss.
Since we're only sending 4MB of data, set a TCP_WINDOW_CLAMP to 200k.
This seems to make virtio happy while having little impact since we're
primarily interested in testing the sender, and the test doesn't
currently enable BIG TCP.
Running socat over virtio loop for 2 sec on a debug kernel shows:
TcpOutSegs 27327 0.0
TcpRetransSegs 83 0.0
TcpOutSegs 30012 0.0
TcpRetransSegs 80 0.0
TcpOutSegs 28767 0.0
TcpRetransSegs 77 0.0
But with the clamp the 3 attempts show no retransmit:
TcpOutSegs 31537 0.0
TcpRetransSegs 0 0.0
TcpOutSegs 30323 0.0
TcpRetransSegs 0 0.0
TcpOutSegs 28700 0.0
TcpRetransSegs 0 0.0
Since we expect no receiver-related drops now we can significantly
increase test's sensitivity to drops.
All the testing we do in NIPA uses cubic.
Link: https://patch.msgid.link/20260223204030.4142884-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
We see quite a few flakes during the TSO test against virtualized
devices in NIPA. There's often 10-30 retransmissions during the
test. Sometimes as many as 100. Set the retransmission threshold
at 1/4th of the wire frame target.
Link: https://patch.msgid.link/20250815224100.363438-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Merge in late fixes to prepare for the 6.17 net-next PR.
Conflicts:
net/core/neighbour.c
1bbb76a899 ("neighbour: Fix null-ptr-deref in neigh_flush_dev().")
13a936bb99 ("neighbour: Protect tbl->phash_buckets[] with a dedicated mutex.")
03dc03fa04 ("neighbor: Add NTF_EXT_VALIDATED flag for externally validated entries")
Adjacent changes:
drivers/net/usb/usbnet.c
0d9cfc9b8c ("net: usbnet: Avoid potential RCU stall on LINK_CHANGE event")
2c04d279e8 ("net: usb: Convert tasklet API to new bottom half workqueue mechanism")
net/ipv6/route.c
31d7d67ba1 ("ipv6: annotate data-races around rt->fib6_nsiblings")
1caf272972 ("ipv6: adopt dst_dev() helper")
3b3ccf9ed0 ("net: Remove unnecessary NULL check for lwtunnel_fill_encap()")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The non-tunneled tso6 test case was showing up as:
ok 8 tso.ipv4
This is because of the way test_builder() uses the inner_ipver arg in
test naming, and how test_info is iterated over in main(). Given that
some tunnels not supported yet, e.g. ipip or sit, only support ipv4 or
ipv6 as the inner network protocol, I think the best fix here is to
call test_builder() in separate branches for tunneled and non-tunneled
tests, and to make supported inner l3 types an explicit attribute of
tunnel test cases.
# Detected qstat for LSO wire-packets
TAP version 13
1..14
ok 1 tso.ipv4
# Testing with mangleid enabled
ok 2 tso.vxlan4_ipv4
ok 3 tso.vxlan4_ipv6
# Testing with mangleid enabled
ok 4 tso.vxlan_csum4_ipv4
ok 5 tso.vxlan_csum4_ipv6
# Testing with mangleid enabled
ok 6 tso.gre4_ipv4
ok 7 tso.gre4_ipv6
ok 8 tso.ipv6
# Testing with mangleid enabled
ok 9 tso.vxlan6_ipv4
ok 10 tso.vxlan6_ipv6
# Testing with mangleid enabled
ok 11 tso.vxlan_csum6_ipv4
ok 12 tso.vxlan_csum6_ipv6
# Testing with mangleid enabled
ok 13 tso.gre6_ipv4
ok 14 tso.gre6_ipv6
# Totals: pass:14 fail:0 xfail:0 xpass:0 skip:0 error:0
Fixes: 0d0f4174f6 ("selftests: drv-net: add a simple TSO test")
Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com>
Link: https://patch.msgid.link/20250723184740.4075410-4-daniel.zahka@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When vxlan is used with ipv6 as the outer network header, the correct
ip link parameters for acheiving the SKB_GSO_UDP_TUNNEL gso type is
"udp6zerocsumtx udp6zerocsumrx". Otherwise the gso type will be
SKB_GSO_UDP_TUNNEL_CSUM.
This bug was the reason for the second of the three possible
invocations of run_one_stream() invocations, so that can be deleted as
well. We only need to test with the feature off and on.
Fixes: 0d0f4174f6 ("selftests: drv-net: add a simple TSO test")
Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com>
Link: https://patch.msgid.link/20250723184740.4075410-3-daniel.zahka@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
tso.py uses the active features at the time of test execution
as the set of available gso features to test. This means if a gso
feature is supported but toggled off at test start, the test will be
skipped with a "Device does not support {feature}" message.
Instead, we can enumerate the set of toggleable features by capturing
the driver's hw_features bitmap. To avoid configuration side-effects
from running the test, we also snapshot the wanted_features flag set
before making any feature changes, and then attempt to restore the
same set of wanted_features before test exit.
Fixes: 0d0f4174f6 ("selftests: drv-net: add a simple TSO test")
Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com>
Link: https://patch.msgid.link/20250723184740.4075410-2-daniel.zahka@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Make require_cmd() calls explicit about whether commands are needed
locally, remotely, or both.
Since require_cmd() defaults to local=True, tests should explicitly set
local=False when commands are only needed remotely.
- socat: Set local=False since it's only needed on remote hosts.
- iperf3: Use single call with both local=True and remote=True since
it's needed on both hosts.
This avoids unnecessary test failures when commands are missing locally
but available remotely where actually needed, and consolidates a
duplicate require_cmd() call into single call that checks both hosts.
Fixes: 0d0f4174f6 ("selftests: drv-net: add a simple TSO test")
Fixes: f1e68a1a4a ("selftests: drv-net: add require_XYZ() helpers for validating env")
Fixes: c76bab22e9 ("selftests: drv-net: rss_input_xfrm: Check test prerequisites before running")
Reviewed-by: Nimrod Oren <noren@nvidia.com>
Signed-off-by: Gal Pressman <gal@nvidia.com>
Link: https://patch.msgid.link/20250723135454.649342-3-gal@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Commit 846742f7e3 ("selftests: drv-net: add a warning for
bkg + shell + terminate") added a warning for bkg() used
with terminate=True. The tso test was missed as we didn't
have it running anywhere in NIPA. Add exit_wait=True, to avoid:
# Warning: combining shell and terminate is risky!
# SIGTERM may not reach the child on zsh/ksh!
getting printed twice for every variant.
Fixes: 0d0f4174f6 ("selftests: drv-net: add a simple TSO test")
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250604012055.891431-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The device type for IPv4 GRE is "gre" not "ipgre",
unlike for IPv6 which uses "ip6gre".
Not sure how I missed this when writing the test, perhaps
because all HW I have access to is on an IPv6-only network.
Fixes: 0d0f4174f6 ("selftests: drv-net: add a simple TSO test")
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250604012031.891242-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Add a simple test for TSO. Send a few MB of data and check device
stats to verify that the device was performing segmentation.
Do the same thing over a few tunnel types.
Injecting GSO packets directly would give us more ability to test
corner cases, but perhaps starting simple is good enough?
# ./ksft-net-drv/drivers/net/hw/tso.py
# Detected qstat for LSO wire-packets
KTAP version 1
1..14
ok 1 tso.ipv4 # SKIP Test requires IPv4 connectivity
ok 2 tso.vxlan4_ipv4 # SKIP Test requires IPv4 connectivity
ok 3 tso.vxlan6_ipv4 # SKIP Test requires IPv4 connectivity
ok 4 tso.vxlan_csum4_ipv4 # SKIP Test requires IPv4 connectivity
ok 5 tso.vxlan_csum6_ipv4 # SKIP Test requires IPv4 connectivity
ok 6 tso.gre4_ipv4 # SKIP Test requires IPv4 connectivity
ok 7 tso.gre6_ipv4 # SKIP Test requires IPv4 connectivity
ok 8 tso.ipv6
ok 9 tso.vxlan4_ipv6
ok 10 tso.vxlan6_ipv6
ok 11 tso.vxlan_csum4_ipv6
ok 12 tso.vxlan_csum6_ipv6
# Testing with mangleid enabled
ok 13 tso.gre4_ipv6
ok 14 tso.gre6_ipv6
# Totals: pass:7 fail:0 xfail:0 xpass:0 skip:7 error:0
Note that the test currently depends on the driver reporting
the LSO count via qstat, which appears to be relatively rare
(virtio, cisco/enic, sfc/efc; but virtio needs host support).
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250218225426.77726-5-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
