With CONFIG_KPROBES_ON_FTRACE enabled on powerpc, ftrace_location_range
returns ftrace location for bpf_fentry_test1 at offset of 4 bytes from
function entry. This is because branch to _mcount function is at offset
of 4 bytes in function profile sequence.
To fix this, add entry_offset of 4 bytes while verifying the address for
kprobe entry address of bpf_fentry_test1 in verify_perf_link_info in
selftest, when CONFIG_KPROBES_ON_FTRACE is enabled.
Disassemble of bpf_fentry_test1:
c000000000e4b080 <bpf_fentry_test1>:
c000000000e4b080: a6 02 08 7c mflr r0
c000000000e4b084: b9 e2 22 4b bl c00000000007933c <_mcount>
c000000000e4b088: 01 00 63 38 addi r3,r3,1
c000000000e4b08c: b4 07 63 7c extsw r3,r3
c000000000e4b090: 20 00 80 4e blr
When CONFIG_PPC_FTRACE_OUT_OF_LINE [1] is enabled, these function profile
sequence is moved out of line with an unconditional branch at offset 0.
So, the test works without altering the offset for
'CONFIG_KPROBES_ON_FTRACE && CONFIG_PPC_FTRACE_OUT_OF_LINE' case.
Disassemble of bpf_fentry_test1:
c000000000f95190 <bpf_fentry_test1>:
c000000000f95190: 00 00 00 60 nop
c000000000f95194: 01 00 63 38 addi r3,r3,1
c000000000f95198: b4 07 63 7c extsw r3,r3
c000000000f9519c: 20 00 80 4e blr
[1] https://lore.kernel.org/all/20241030070850.1361304-13-hbathini@linux.ibm.com/
Fixes: 23cf7aa539 ("selftests/bpf: Add selftest for fill_link_info")
Signed-off-by: Saket Kumar Bhaskar <skb99@linux.ibm.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20241209065720.234344-1-skb99@linux.ibm.com
Add assertions in `bpf_link_info.uprobe_multi` test to verify that
`count` and `path_size` fields are correctly populated when the fields
are unset.
This tests a previous bug where the `path_size` field was not populated
when `path` and `path_size` were unset.
Signed-off-by: Tyrone Wu <wudevelops@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20241011000803.681190-2-wudevelops@gmail.com
Static ksyms often have problems because the number of symbols exceeds the
MAX_SYMS limit. Like changing the MAX_SYMS from 300000 to 400000 in
commit e76a014334a6("selftests/bpf: Bump and validate MAX_SYMS") solves
the problem somewhat, but it's not the perfect way.
This commit uses dynamic memory allocation, which completely solves the
problem caused by the limitation of the number of kallsyms. At the same
time, add APIs:
load_kallsyms_local()
ksym_search_local()
ksym_get_addr_local()
free_kallsyms_local()
There are used to solve the problem of selftests/bpf updating kallsyms
after attach new symbols during testmod testing.
Signed-off-by: Rong Tao <rongtao@cestc.cn>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/tencent_C9BDA68F9221F21BE4081566A55D66A9700A@qq.com
Add selftest for the fill_link_info of uprobe, kprobe and tracepoint.
The result:
$ tools/testing/selftests/bpf/test_progs --name=fill_link_info
#79/1 fill_link_info/kprobe_link_info:OK
#79/2 fill_link_info/kretprobe_link_info:OK
#79/3 fill_link_info/kprobe_invalid_ubuff:OK
#79/4 fill_link_info/tracepoint_link_info:OK
#79/5 fill_link_info/uprobe_link_info:OK
#79/6 fill_link_info/uretprobe_link_info:OK
#79/7 fill_link_info/kprobe_multi_link_info:OK
#79/8 fill_link_info/kretprobe_multi_link_info:OK
#79/9 fill_link_info/kprobe_multi_invalid_ubuff:OK
#79 fill_link_info:OK
Summary: 1/9 PASSED, 0 SKIPPED, 0 FAILED
The test case for kprobe_multi won't be run on aarch64, as it is not
supported.
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20230813141900.1268-3-laoar.shao@gmail.com