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
