linux-stable.git/tools/testing/selftests/bpf, branch linux-5.15.y

selftests/bpf: Improve reliability of test_perf_branches_no_hw()

2026-01-19T12:09:32+00:00

[ Upstream commit ae24fc8a16b0481ea8c5acbc66453c49ec0431c4 ]

Currently, test_perf_branches_no_hw() relies on the busy loop within
test_perf_branches_common() being slow enough to allow at least one
perf event sample tick to occur before starting to tear down the
backing perf event BPF program. With a relatively small fixed
iteration count of 1,000,000, this is not guaranteed on modern fast
CPUs, resulting in the test run to subsequently fail with the
following:

bpf_testmod.ko is already unloaded.
Loading bpf_testmod.ko...
Successfully loaded bpf_testmod.ko.
test_perf_branches_common:PASS:test_perf_branches_load 0 nsec
test_perf_branches_common:PASS:attach_perf_event 0 nsec
test_perf_branches_common:PASS:set_affinity 0 nsec
check_good_sample:PASS:output not valid 0 nsec
check_good_sample:PASS:read_branches_size 0 nsec
check_good_sample:PASS:read_branches_stack 0 nsec
check_good_sample:PASS:read_branches_stack 0 nsec
check_good_sample:PASS:read_branches_global 0 nsec
check_good_sample:PASS:read_branches_global 0 nsec
check_good_sample:PASS:read_branches_size 0 nsec
test_perf_branches_no_hw:PASS:perf_event_open 0 nsec
test_perf_branches_common:PASS:test_perf_branches_load 0 nsec
test_perf_branches_common:PASS:attach_perf_event 0 nsec
test_perf_branches_common:PASS:set_affinity 0 nsec
check_bad_sample:FAIL:output not valid no valid sample from prog
Summary: 0/1 PASSED, 0 SKIPPED, 1 FAILED
Successfully unloaded bpf_testmod.ko.

On a modern CPU (i.e. one with a 3.5 GHz clock rate), executing 1
million increments of a volatile integer can take significantly less
than 1 millisecond. If the spin loop and detachment of the perf event
BPF program elapses before the first 1 ms sampling interval elapses,
the perf event will never end up firing. Fix this by bumping the loop
iteration counter a little within test_perf_branches_common(), along
with ensuring adding another loop termination condition which is
directly influenced by the backing perf event BPF program
executing. Notably, a concious decision was made to not adjust the
sample_freq value as that is just not a reliable way to go about
fixing the problem. It effectively still leaves the race window open.

Fixes: 67306f84ca78c ("selftests/bpf: Add bpf_read_branch_records() selftest")
Signed-off-by: Matt Bobrowski 
Reviewed-by: Jiri Olsa 
Link: https://lore.kernel.org/r/20251119143540.2911424-1-mattbobrowski@google.com
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Sasha Levin

selftests/bpf: skip test_perf_branches_hw() on unsupported platforms

2026-01-19T12:09:32+00:00

[ Upstream commit 27746aaf1b20172f0859546c4a3e82eca459f680 ]

Gracefully skip the test_perf_branches_hw subtest on platforms that
do not support LBR or require specialized perf event attributes
to enable branch sampling.

For example, AMD's Milan (Zen 3) supports BRS rather than traditional
LBR. This requires specific configurations (attr.type = PERF_TYPE_RAW,
attr.config = RETIRED_TAKEN_BRANCH_INSTRUCTIONS) that differ from the
generic setup used within this test. Notably, it also probably doesn't
hold much value to special case perf event configurations for selected
micro architectures.

Fixes: 67306f84ca78c ("selftests/bpf: Add bpf_read_branch_records() selftest")
Signed-off-by: Matt Bobrowski 
Acked-by: Song Liu 
Link: https://lore.kernel.org/r/20251120142059.2836181-1-mattbobrowski@google.com
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Sasha Levin

selftests/bpf: Fix failure paths in send_signal test

2026-01-19T12:09:29+00:00

[ Upstream commit c13339039891dbdfa6c1972f0483bd07f610b776 ]

When test_send_signal_kern__open_and_load() fails parent closes the
pipe which cases ASSERT_EQ(read(pipe_p2c...)) to fail, but child
continues and enters infinite loop, while parent is stuck in wait(NULL).
Other error paths have similar issue, so kill the child before waiting on it.

The bug was discovered while compiling all of selftests with -O1 instead of -O2
which caused progs/test_send_signal_kern.c to fail to load.

Fixes: ab8b7f0cb358 ("tools/bpf: Add self tests for bpf_send_signal_thread()")
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Andrii Nakryiko 
Acked-by: Eduard Zingerman 
Link: https://lore.kernel.org/bpf/20251113171153.2583-1-alexei.starovoitov@gmail.com
Signed-off-by: Sasha Levin

selftests/bpf: Don't rely on preserving volatile in PT_REGS macros in loop3

2025-12-06T21:09:36+00:00

commit 70bc793382a0e37ba4e35e4d1a317b280b829a44 upstream.

PT_REGS*() macro on some architectures force-cast struct pt_regs to
other types (user_pt_regs, etc) and might drop volatile modifiers, if any.
Volatile isn't really required as pt_regs value isn't supposed to change
during the BPF program run, so this is correct behavior.

But progs/loop3.c relies on that volatile modifier to ensure that loop
is preserved. Fix loop3.c by declaring i and sum variables as volatile
instead. It preserves the loop and makes the test pass on all
architectures (including s390x which is currently broken).

Fixes: 3cc31d794097 ("libbpf: Normalize PT_REGS_xxx() macro definitions")
Signed-off-by: Andrii Nakryiko 
Signed-off-by: Daniel Borkmann 
Link: https://lore.kernel.org/bpf/20220106205156.955373-1-andrii@kernel.org
Signed-off-by: Greg Kroah-Hartman

selftests/bpf: Fix bpf_prog_detach2 usage in test_lirc_mode2

2025-12-06T21:09:16+00:00

[ Upstream commit 98857d111c53954aa038fcbc4cf48873e4240f7c ]

Commit e9fc3ce99b34 ("libbpf: Streamline error reporting for high-level
APIs") redefined the way that bpf_prog_detach2() returns. Therefore, adapt
the usage in test_lirc_mode2_user.c.

Signed-off-by: Ricardo B. Marlière 
Signed-off-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/20250828-selftests-bpf-v1-1-c7811cd8b98c@suse.com
Signed-off-by: Sasha Levin

tools/testing/selftests/bpf/test_tc_tunnel.sh: Fix wait for server bind

2025-03-13T11:50:00+00:00

[ Upstream commit e2f0791124a1b6ca8d570110cbd487969d9d41ef ]

Commit f803bcf9208a ("selftests/bpf: Prevent client connect before
server bind in test_tc_tunnel.sh") added code that waits for the
netcat server to start before the netcat client attempts to connect to
it. However, not all calls to 'server_listen' were guarded.

This patch adds the existing 'wait_for_port' guard after the remaining
call to 'server_listen'.

Fixes: f803bcf9208a ("selftests/bpf: Prevent client connect before server bind in test_tc_tunnel.sh")
Signed-off-by: Marco Leogrande 
Acked-by: Stanislav Fomichev 
Link: https://lore.kernel.org/r/20241202204530.1143448-1-leogrande@google.com
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Sasha Levin

selftests/bpf: Add push/pop checking for msg_verify_data in test_sockmap

2024-12-14T18:50:57+00:00

[ Upstream commit 862087c3d36219ed44569666eb263efc97f00c9a ]

Add push/pop checking for msg_verify_data in test_sockmap, except for
pop/push with cork tests, in these tests the logic will be different.
1. With corking, pop/push might not be invoked in each sendmsg, it makes
the layout of the received data difficult
2. It makes it hard to calculate the total_bytes in the recvmsg
Temporarily skip the data integrity test for these cases now, added a TODO

Fixes: ee9b352ce465 ("selftests/bpf: Fix msg_verify_data in test_sockmap")
Signed-off-by: Zijian Zhang 
Reviewed-by: John Fastabend 
Link: https://lore.kernel.org/r/20241106222520.527076-5-zijianzhang@bytedance.com
Signed-off-by: Martin KaFai Lau 
Signed-off-by: Sasha Levin

selftests/bpf: Fix total_bytes in msg_loop_rx in test_sockmap

2024-12-14T18:50:57+00:00

[ Upstream commit 523dffccbadea0cfd65f1ff04944b864c558c4a8 ]

total_bytes in msg_loop_rx should also take push into account, otherwise
total_bytes will be a smaller value, which makes the msg_loop_rx end early.

Besides, total_bytes has already taken pop into account, so we don't need
to subtract some bytes from iov_buf in sendmsg_test. The additional
subtraction may make total_bytes a negative number, and msg_loop_rx will
just end without checking anything.

Fixes: 18d4e900a450 ("bpf: Selftests, improve test_sockmap total bytes counter")
Fixes: d69672147faa ("selftests, bpf: Add one test for sockmap with strparser")
Signed-off-by: Zijian Zhang 
Reviewed-by: John Fastabend 
Link: https://lore.kernel.org/r/20241106222520.527076-4-zijianzhang@bytedance.com
Signed-off-by: Martin KaFai Lau 
Signed-off-by: Sasha Levin

selftests, bpf: Add one test for sockmap with strparser

2024-12-14T18:50:57+00:00

[ Upstream commit d69672147faa2a7671c0779fa5b9ad99e4fca4e3 ]

Add the test to check sockmap with strparser is working well.

Signed-off-by: Liu Jian 
Signed-off-by: Daniel Borkmann 
Acked-by: John Fastabend 
Link: https://lore.kernel.org/bpf/20211029141216.211899-3-liujian56@huawei.com
Stable-dep-of: 523dffccbade ("selftests/bpf: Fix total_bytes in msg_loop_rx in test_sockmap")
Signed-off-by: Sasha Levin

selftests/bpf: Fix SENDPAGE data logic in test_sockmap

2024-12-14T18:50:57+00:00

[ Upstream commit 4095031463d4e99b534d2cd82035a417295764ae ]

In the SENDPAGE test, "opt->iov_length * cnt" size of data will be sent
cnt times by sendfile.
1. In push/pop tests, they will be invoked cnt times, for the simplicity of
msg_verify_data, change chunk_sz to iov_length
2. Change iov_length in test_send_large from 1024 to 8192. We have pop test
where txmsg_start_pop is 4096. 4096 > 1024, an error will be returned.

Fixes: 328aa08a081b ("bpf: Selftests, break down test_sockmap into subtests")
Signed-off-by: Zijian Zhang 
Reviewed-by: John Fastabend 
Link: https://lore.kernel.org/r/20241106222520.527076-3-zijianzhang@bytedance.com
Signed-off-by: Martin KaFai Lau 
Signed-off-by: Sasha Levin