After commit 9298e63eaf ("bpf/tests: Add exhaustive tests of ALU
operand magnitudes"), when modprobe test_bpf.ko with JIT on mips64,
there exists segment fault due to the following reason:
[...]
ALU64_MOV_X: all register value magnitudes jited:1
Break instruction in kernel code[#1]
[...]
It seems that the related JIT implementations of some test cases
in test_bpf() have problems. At this moment, I do not care about
the segment fault while I just want to verify the test cases of
tail calls.
Based on the above background and motivation, add the following
module parameter test_suite to the test_bpf.ko:
test_suite=<string>: only the specified test suite will be run, the
string can be "test_bpf", "test_tail_calls" or "test_skb_segment".
If test_suite is not specified, but test_id, test_name or test_range
is specified, set 'test_bpf' as the default test suite. This is useful
to only test the corresponding test suite when specifying the valid
test_suite string.
Any invalid test suite will result in -EINVAL being returned and no
tests being run. If the test_suite is not specified or specified as
empty string, it does not change the current logic, all of the test
cases will be run.
Here are some test results:
# dmesg -c
# modprobe test_bpf
# dmesg | grep Summary
test_bpf: Summary: 1009 PASSED, 0 FAILED, [0/997 JIT'ed]
test_bpf: test_tail_calls: Summary: 8 PASSED, 0 FAILED, [0/8 JIT'ed]
test_bpf: test_skb_segment: Summary: 2 PASSED, 0 FAILED
# rmmod test_bpf
# dmesg -c
# modprobe test_bpf test_suite=test_bpf
# dmesg | tail -1
test_bpf: Summary: 1009 PASSED, 0 FAILED, [0/997 JIT'ed]
# rmmod test_bpf
# dmesg -c
# modprobe test_bpf test_suite=test_tail_calls
# dmesg
test_bpf: #0 Tail call leaf jited:0 21 PASS
[...]
test_bpf: #7 Tail call error path, index out of range jited:0 32 PASS
test_bpf: test_tail_calls: Summary: 8 PASSED, 0 FAILED, [0/8 JIT'ed]
# rmmod test_bpf
# dmesg -c
# modprobe test_bpf test_suite=test_skb_segment
# dmesg
test_bpf: #0 gso_with_rx_frags PASS
test_bpf: #1 gso_linear_no_head_frag PASS
test_bpf: test_skb_segment: Summary: 2 PASSED, 0 FAILED
# rmmod test_bpf
# dmesg -c
# modprobe test_bpf test_id=1
# dmesg
test_bpf: test_bpf: set 'test_bpf' as the default test_suite.
test_bpf: #1 TXA jited:0 54 51 50 PASS
test_bpf: Summary: 1 PASSED, 0 FAILED, [0/1 JIT'ed]
# rmmod test_bpf
# dmesg -c
# modprobe test_bpf test_suite=test_bpf test_name=TXA
# dmesg
test_bpf: #1 TXA jited:0 54 50 51 PASS
test_bpf: Summary: 1 PASSED, 0 FAILED, [0/1 JIT'ed]
# rmmod test_bpf
# dmesg -c
# modprobe test_bpf test_suite=test_tail_calls test_range=6,7
# dmesg
test_bpf: #6 Tail call error path, NULL target jited:0 41 PASS
test_bpf: #7 Tail call error path, index out of range jited:0 32 PASS
test_bpf: test_tail_calls: Summary: 2 PASSED, 0 FAILED, [0/2 JIT'ed]
# rmmod test_bpf
# dmesg -c
# modprobe test_bpf test_suite=test_skb_segment test_id=1
# dmesg
test_bpf: #1 gso_linear_no_head_frag PASS
test_bpf: test_skb_segment: Summary: 1 PASSED, 0 FAILED
By the way, the above segment fault has been fixed in the latest bpf-next
tree which contains the mips64 JIT rework.
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Acked-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Link: https://lore.kernel.org/bpf/1635384321-28128-1-git-send-email-yangtiezhu@loongson.cn
This patch expands the register-clobbering-during-function-call tests
to cover more all ALU32/64 MUL, DIV and MOD operations and all ATOMIC
operations. In short, if a JIT implements a complex operation with
a call to an external function, it must make sure to save and restore
all its caller-saved registers that may be clobbered by the call.
Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211001130348.3670534-6-johan.almbladh@anyfinetworks.com
This patch adds a set of tests for ALU64 and ALU32 arithmetic and bitwise
logical operations to verify correctness for all possible magnitudes of
the register and immediate operands. Mainly intended for JIT testing.
The patch introduces a pattern generator that can be used to drive
extensive tests of different kinds of operations. It is parameterized
to allow tuning of the operand combinations to test.
Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210914091842.4186267-5-johan.almbladh@anyfinetworks.com
The test suite used to call any fill_helper callbacks to generate eBPF
program data for all test cases at once. This caused ballooning memory
requirements as more extensive test cases were added. Now the each
fill_helper is called before the test is run and the allocated memory
released afterwards, before the next test case is processed.
Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210914091842.4186267-3-johan.almbladh@anyfinetworks.com
This patch allows a test cast to specify the number of runs to use. For
compatibility with existing test case definitions, the default value 0
is interpreted as MAX_TESTRUNS.
A reduced number of runs is useful for complex test programs where 1000
runs may take a very long time. Instead of reducing what is tested, one
can instead reduce the number of times the test is run.
Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210914091842.4186267-2-johan.almbladh@anyfinetworks.com
Turn BPF_PROG_RUN into a proper always inlined function. No functional and
performance changes are intended, but it makes it much easier to understand
what's going on with how BPF programs are actually get executed. It's more
obvious what types and callbacks are expected. Also extra () around input
parameters can be dropped, as well as `__` variable prefixes intended to avoid
naming collisions, which makes the code simpler to read and write.
This refactoring also highlighted one extra issue. BPF_PROG_RUN is both
a macro and an enum value (BPF_PROG_RUN == BPF_PROG_TEST_RUN). Turning
BPF_PROG_RUN into a function causes naming conflict compilation error. So
rename BPF_PROG_RUN into lower-case bpf_prog_run(), similar to
bpf_prog_run_xdp(), bpf_prog_run_pin_on_cpu(), etc. All existing callers of
BPF_PROG_RUN, the macro, are switched to bpf_prog_run() explicitly.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210815070609.987780-2-andrii@kernel.org
Each test case can have a set of sub-tests, where each sub-test can
run the cBPF/eBPF test snippet with its own data_size and expected
result. Before, the end of the sub-test array was indicated by both
data_size and result being zero. However, most or all of the internal
eBPF tests has a data_size of zero already. When such a test also had
an expected value of zero, the test was never run but reported as
PASS anyway.
Now the test runner always runs the first sub-test, regardless of the
data_size and result values. The sub-test array zero-termination only
applies for any additional sub-tests.
There are other ways fix it of course, but this solution at least
removes the surprise of eBPF tests with a zero result always succeeding.
Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210721103822.3755111-1-johan.almbladh@anyfinetworks.com
A subsequent patch will add additional atomic operations. These new
operations will use the same opcode field as the existing XADD, with
the immediate discriminating different operations.
In preparation, rename the instruction mode BPF_ATOMIC and start
calling the zero immediate BPF_ADD.
This is possible (doesn't break existing valid BPF progs) because the
immediate field is currently reserved MBZ and BPF_ADD is zero.
All uses are removed from the tree but the BPF_XADD definition is
kept around to avoid breaking builds for people including kernel
headers.
Signed-off-by: Brendan Jackman <jackmanb@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Björn Töpel <bjorn.topel@gmail.com>
Link: https://lore.kernel.org/bpf/20210114181751.768687-5-jackmanb@google.com
This reverts commit 3203c90100 ("test_bpf: flag tests that cannot
be jited on s390").
The s390 bpf JIT previously had a restriction on the maximum program
size, which required some tests in test_bpf to be flagged as expected
failures. The program size limitation has been removed, and the tests
now pass, so these tests should no longer be flagged.
Fixes: d1242b10ff ("s390/bpf: Remove JITed image size limitations")
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/bpf/20200716143931.330122-1-seth.forshee@canonical.com