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
Adding fill_link_info test for perf event and testing we
get its values back through the bpf_link_info interface.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240119110505.400573-7-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Adding fill_link_info test for uprobe_multi link.
Setting up uprobes with bogus ref_ctr_offsets and cookie values
to test all the bpf_link_info::uprobe_multi fields.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Song Liu <song@kernel.org>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/bpf/20231125193130.834322-6-jolsa@kernel.org
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
Saket Kumar Bhaskar
Jiri Olsa
Yafang Shao