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Fix a bunch of potentially unitialized variable usage warnings that are
reported by GCC in -O2 mode. Also silence overzealous stringop-truncation
class of warnings.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20231006175744.3136675-1-andrii@kernel.org
Currently, there exists a system-wide setting related to CPU security
mitigations, denoted as 'mitigations='. When set to 'mitigations=off', it
deactivates all optional CPU mitigations. Therefore, if we implement a
system-wide 'mitigations=off' setting, it should inherently bypass Spectre
v1 and Spectre v4 in the BPF subsystem.
Please note that there is also a more specific 'nospectre_v1' setting on
x86 and ppc architectures, though it is not currently exported. For the
time being, let's disregard more fine-grained options.
This idea emerged during our discussion about potential Spectre v1 attacks
with Luis [0].
[0] https://lore.kernel.org/bpf/b4fc15f7-b204-767e-ebb9-fdb4233961fb@iogearbox.net
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Song Liu <song@kernel.org>
Acked-by: KP Singh <kpsingh@kernel.org>
Cc: Luis Gerhorst <gerhorst@cs.fau.de>
Link: https://lore.kernel.org/bpf/20231005084123.1338-1-laoar.shao@gmail.com
The comment used to say:
> Restore data saved by bpf_compute_data_pointers().
But bpf_compute_data_pointers() does not save the data;
bpf_compute_and_save_data_end() does.
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20231005072137.29870-1-akihiko.odaki@daynix.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
CONFIG_VSOCKETS is required by BPF selftests, otherwise we get errors
like this:
./test_progs:socket_loopback_reuseport:386: socket:
Address family not supported by protocol
socket_loopback_reuseport:FAIL:386
./test_progs:vsock_unix_redir_connectible:1496:
vsock_socketpair_connectible() failed
vsock_unix_redir_connectible:FAIL:1496
So this patch enables it in tools/testing/selftests/bpf/config.
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Link: https://lore.kernel.org/r/472e73d285db2ea59aca9bbb95eb5d4048327588.1696490003.git.geliang.tang@suse.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Björn Töpel says:
====================
From: Björn Töpel <bjorn@rivosinc.com>
Yet another "more cross-building support for RISC-V" series.
An example how to invoke a gen_tar build:
| make ARCH=riscv CROSS_COMPILE=riscv64-linux-gnu- CC=riscv64-linux-gnu-gcc \
| HOSTCC=gcc O=/workspace/kbuild FORMAT= \
| SKIP_TARGETS="arm64 ia64 powerpc sparc64 x86 sgx" -j $(($(nproc)-1)) \
| -C tools/testing/selftests gen_tar
Björn
====================
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
The uprobe_multi program was not picked up for the gen_tar target. Fix
by adding it to TEST_GEN_FILES.
Signed-off-by: Björn Töpel <bjorn@rivosinc.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20231004122721.54525-4-bjorn@kernel.org
Some userland programs in the BPF test suite, e.g. urandom_read, is
missing cross-build support. Add cross-build support for these
programs
Signed-off-by: Björn Töpel <bjorn@rivosinc.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20231004122721.54525-2-bjorn@kernel.org
Björn Töpel says:
====================
From: Björn Töpel <bjorn@rivosinc.com>
Commit 08d0ce30e0e4 ("riscv: Implement syscall wrappers") introduced
some regressions in libbpf, and the kselftests BPF suite, which are
fixed with these three patches.
Note that there's an outstanding fix [1] for ftrace syscall tracing
which is also a fallout from the commit above.
Björn
[1] https://lore.kernel.org/linux-riscv/20231003182407.32198-1-alexghiti@rivosinc.com/
Alexandre Ghiti (1):
libbpf: Fix syscall access arguments on riscv
====================
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Add missing sys_nanosleep name for RISC-V, which is used by some tests
(e.g. attach_probe).
Fixes: 08d0ce30e0e4 ("riscv: Implement syscall wrappers")
Signed-off-by: Björn Töpel <bjorn@rivosinc.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Link: https://lore.kernel.org/bpf/20231004110905.49024-4-bjorn@kernel.org
SYS_PREFIX was missing for a RISC-V, which made a couple of kprobe
tests fail.
Add missing SYS_PREFIX for RISC-V.
Fixes: 08d0ce30e0e4 ("riscv: Implement syscall wrappers")
Signed-off-by: Björn Töpel <bjorn@rivosinc.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Link: https://lore.kernel.org/bpf/20231004110905.49024-3-bjorn@kernel.org
Tushar Vyavahare says:
====================
Implement a test for the SHARED_UMEM feature in this patch set and make
necessary changes/improvements. Ensure that the framework now supports
different streams for different sockets.
v2->v3:
- Set the sock_num at the end of the while loop.
- Declare xsk at the top of the while loop.
v1->v2:
- Remove generate_mac_addresses() and generate mac addresses based on
the number of sockets in __test_spec_init() function. [Magnus]
- Update Makefile to include find_bit.c for compiling xskxceiver.
- Add bitmap_full() function to verify all bits are set to break the
while loop in the receive_pkts() and send_pkts() functions.
- Replace __test_and_set_bit() function with __set_bit() function.
- Add single return check for wait_for_tx_completion() function call.
Patch series summary:
1: Move the packet stream from the ifobject struct to the xsk_socket_info
struct to enable the use of different streams for different sockets
This will facilitate the sending and receiving of data from multiple
sockets simultaneously using the SHARED_XDP_UMEM feature.
It gives flexibility of send/recive individual traffic on particular
socket.
2: Rename the header file to a generic name so that it can be used by all
future XDP programs.
3: Move the src_mac and dst_mac fields from the ifobject structure to the
xsk_socket_info structure to achieve per-socket MAC address assignment.
Require this in order to steer traffic to various sockets in subsequent
patches.
4: Improve the receive_pkt() function to enable it to receive packets from
multiple sockets. Define a sock_num variable to iterate through all the
sockets in the Rx path. Add nb_valid_entries to check that all the
expected number of packets are received.
5: The pkt_set() function no longer needs the umem parameter. This commit
removes the umem parameter from the pkt_set() function.
6: Iterate over all the sockets in the send pkts function. Update
send_pkts() to handle multiple sockets for sending packets. Multiple TX
sockets are utilized alternately based on the batch size for improve
packet transmission.
7: Modify xsk_update_xskmap() to accept the index as an argument, enabling
the addition of multiple sockets to xskmap.
8: Add a new test for testing shared umem feature. This is accomplished by
adding a new XDP program and using the multiple sockets. The new XDP
program redirects the packets based on the destination MAC address.
====================
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Add a new test for testing shared umem feature. This is accomplished by
adding a new XDP program and using the multiple sockets.
The new XDP program redirects the packets based on the destination MAC
address.
Signed-off-by: Tushar Vyavahare <tushar.vyavahare@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20230927135241.2287547-9-tushar.vyavahare@intel.com
Modify xsk_update_xskmap() to accept the index as an argument, enabling
the addition of multiple sockets to xskmap.
Signed-off-by: Tushar Vyavahare <tushar.vyavahare@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20230927135241.2287547-8-tushar.vyavahare@intel.com
Update send_pkts() to handle multiple sockets for sending packets.
Multiple TX sockets are utilized alternately based on the batch size for
improve packet transmission.
Signed-off-by: Tushar Vyavahare <tushar.vyavahare@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20230927135241.2287547-7-tushar.vyavahare@intel.com
The pkt_set() function no longer needs the umem parameter. This commit
removes the umem parameter from the pkt_set() function.
Signed-off-by: Tushar Vyavahare <tushar.vyavahare@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20230927135241.2287547-6-tushar.vyavahare@intel.com
Improve the receive_pkt() function to enable it to receive packets from
multiple sockets. Define a sock_num variable to iterate through all the
sockets in the Rx path. Add nb_valid_entries to check that all the
expected number of packets are received.
Revise the function __receive_pkts() to only inspect the receive ring
once, handle any received packets, and promptly return. Implement a bitmap
to store the value of number of sockets. Update Makefile to include
find_bit.c for compiling xskxceiver.
Signed-off-by: Tushar Vyavahare <tushar.vyavahare@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20230927135241.2287547-5-tushar.vyavahare@intel.com
Move the src_mac and dst_mac fields from the ifobject structure to the
xsk_socket_info structure to achieve per-socket MAC address assignment.
Require this in order to steer traffic to various sockets in subsequent
patches.
Signed-off-by: Tushar Vyavahare <tushar.vyavahare@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20230927135241.2287547-4-tushar.vyavahare@intel.com
Rename the header file to a generic name so that it can be used by all
future XDP programs. Ensure that the xsk_xdp_common.h header file includes
include guards.
Signed-off-by: Tushar Vyavahare <tushar.vyavahare@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20230927135241.2287547-3-tushar.vyavahare@intel.com
Move the packet stream from the ifobject struct to the xsk_socket_info
struct to enable the use of different streams for different sockets. This
will facilitate the sending and receiving of data from multiple sockets
simultaneously using the SHARED_XDP_UMEM feature.
Signed-off-by: Tushar Vyavahare <tushar.vyavahare@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20230927135241.2287547-2-tushar.vyavahare@intel.com
Golang symbols in ELF files are different from C/C++
which contains special characters like '*', '(' and ')'.
With generics, things get more complicated, there are
symbols like:
github.com/cilium/ebpf/internal.(*Deque[go.shape.interface { Format(fmt.State, int32); TypeName() string;github.com/cilium/ebpf/btf.copy() github.com/cilium/ebpf/btf.Type}]).Grow
Matching such symbols using `%m[^\n]` in sscanf, this
excludes newline which typically does not appear in ELF
symbols. This should work in most use-cases and also
work for unicode letters in identifiers. If newline do
show up in ELF symbols, users can still attach to such
symbol by specifying bpf_uprobe_opts::func_name.
A working example can be found at this repo ([0]).
[0]: https://github.com/chenhengqi/libbpf-go-symbols
Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230929155954.92448-1-hengqi.chen@gmail.com
The sanitizer flag, which is supported by both clang and gcc, would make
it easier to debug array index out-of-bounds problems in these programs.
Make the Makfile smarter to detect ubsan support from the compiler and
add the '-fsanitize=bounds' accordingly.
Suggested-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Jinghao Jia <jinghao@linux.ibm.com>
Signed-off-by: Jinghao Jia <jinghao7@illinois.edu>
Signed-off-by: Ruowen Qin <ruowenq2@illinois.edu>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20230927045030.224548-2-ruowenq2@illinois.edu
Jiri Olsa says:
====================
hi,
at the moment we can't retrieve the number of missed kprobe
executions and subsequent execution of BPF programs.
This patchset adds:
- counting of missed execution on attach layer for:
. kprobes attached through perf link (kprobe/ftrace)
. kprobes attached through kprobe.multi link (fprobe)
- counting of recursion_misses for BPF kprobe programs
It's still technically possible to create kprobe without perf link (using
SET_BPF perf ioctl) in which case we don't have a way to retrieve the kprobe's
'missed' count. However both libbpf and cilium/ebpf libraries use perf link
if it's available, and for old kernels without perf link support we can use
BPF program to retrieve the kprobe missed count.
v3 changes:
- added acks [Song]
- make test_missed not serial [Andrii]
Also available at:
https://git.kernel.org/pub/scm/linux/kernel/git/jolsa/perf.git
bpf/missed_stats
thanks,
jirka
====================
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Adding selftest that puts kprobe on bpf_fentry_test1 that calls bpf_printk
and invokes bpf_trace_printk tracepoint. The bpf_trace_printk tracepoint
has test[234] programs attached to it.
Because kprobe execution goes through bpf_prog_active check, programs
attached to the tracepoint will fail the recursion check and increment the
recursion_misses stats.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Song Liu <song@kernel.org>
Reviewed-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/bpf/20230920213145.1941596-10-jolsa@kernel.org
Adding selftest that puts kprobe.multi on bpf_fentry_test1 that
calls bpf_kfunc_common_test kfunc which has 3 perf event kprobes
and 1 kprobe.multi attached.
Because fprobe (kprobe.multi attach layear) does not have strict
recursion check the kprobe's bpf_prog_active check is hit for test2-5.
Disabling this test for arm64, because there's no fprobe support yet.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Song Liu <song@kernel.org>
Reviewed-by: Song Liu <song@kernel.org>
Acked-by: Hou Tao <houtao1@huawei.com>
Link: https://lore.kernel.org/bpf/20230920213145.1941596-9-jolsa@kernel.org
Adding test that puts kprobe on bpf_fentry_test1 that calls
bpf_kfunc_common_test kfunc, which has also kprobe on.
The latter won't get triggered due to kprobe recursion check
and kprobe missed counter is incremented.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Hou Tao <houtao1@huawei.com>
Link: https://lore.kernel.org/bpf/20230920213145.1941596-8-jolsa@kernel.org
Increase misses stats in case bpf array execution is skipped
because of recursion check in trace_call_bpf.
Adding bpf_prog_inc_misses_counters that increase misses
counts for all bpf programs in bpf_prog_array.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Song Liu <song@kernel.org>
Reviewed-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/bpf/20230920213145.1941596-5-jolsa@kernel.org
Add missed value to kprobe attached through perf link info to
hold the stats of missed kprobe handler execution.
The kprobe's missed counter gets incremented when kprobe handler
is not executed due to another kprobe running on the same cpu.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230920213145.1941596-4-jolsa@kernel.org
Add missed value to kprobe_multi link info to hold the stats of missed
kprobe_multi probe.
The missed counter gets incremented when fprobe fails the recursion
check or there's no rethook available for return probe. In either
case the attached bpf program is not executed.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Song Liu <song@kernel.org>
Reviewed-by: Song Liu <song@kernel.org>
Acked-by: Hou Tao <houtao1@huawei.com>
Link: https://lore.kernel.org/bpf/20230920213145.1941596-3-jolsa@kernel.org
Adding support to gather missed stats for kprobe_multi
programs due to bpf_prog_active protection.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Song Liu <song@kernel.org>
Reviewed-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/bpf/20230920213145.1941596-2-jolsa@kernel.org
Martin Kelly says:
====================
This patch series adds a new ring__ API to libbpf exposing getters for
accessing the individual ringbuffers inside a struct ring_buffer. This is
useful for polling individually, getting available data, or similar use
cases. The API looks like this, and was roughly proposed by Andrii Nakryiko
in another thread:
Getting a ring struct:
struct ring *ring_buffer__ring(struct ring_buffer *rb, unsigned int idx);
Using the ring struct:
unsigned long ring__consumer_pos(const struct ring *r);
unsigned long ring__producer_pos(const struct ring *r);
size_t ring__avail_data_size(const struct ring *r);
size_t ring__size(const struct ring *r);
int ring__map_fd(const struct ring *r);
int ring__consume(struct ring *r);
Changes in v2:
- Addressed all feedback from Andrii Nakryiko
====================
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Add ring__avail_data_size for querying the currently available data in
the ringbuffer, similar to the BPF_RB_AVAIL_DATA flag in
bpf_ringbuf_query. This is racy during ongoing operations but is still
useful for overall information on how a ringbuffer is behaving.
Signed-off-by: Martin Kelly <martin.kelly@crowdstrike.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230925215045.2375758-8-martin.kelly@crowdstrike.com
Switch rb->rings to be an array of pointers instead of a contiguous
block. This allows for each ring pointer to be stable after
ring_buffer__add is called, which allows us to expose struct ring * to
the user without gotchas. Without this change, the realloc in
ring_buffer__add could invalidate a struct ring *, making it unsafe to
give to the user.
Signed-off-by: Martin Kelly <martin.kelly@crowdstrike.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230925215045.2375758-3-martin.kelly@crowdstrike.com
Refactor the cleanup code in ring_buffer__add to use a unified err_out
label. This reduces code duplication, as well as plugging a potential
leak if mmap_sz != (__u64)(size_t)mmap_sz (currently this would miss
unmapping tmp because ringbuf_unmap_ring isn't called).
Signed-off-by: Martin Kelly <martin.kelly@crowdstrike.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230925215045.2375758-2-martin.kelly@crowdstrike.com
Hengqi Chen says:
====================
Dynamic symbols in shared library may have the same name, for example:
$ nm -D /lib/x86_64-linux-gnu/libc.so.6 | grep rwlock_wrlock
000000000009b1a0 T __pthread_rwlock_wrlock@GLIBC_2.2.5
000000000009b1a0 T pthread_rwlock_wrlock@@GLIBC_2.34
000000000009b1a0 T pthread_rwlock_wrlock@GLIBC_2.2.5
$ readelf -W --dyn-syms /lib/x86_64-linux-gnu/libc.so.6 | grep rwlock_wrlock
706: 000000000009b1a0 878 FUNC GLOBAL DEFAULT 15 __pthread_rwlock_wrlock@GLIBC_2.2.5
2568: 000000000009b1a0 878 FUNC GLOBAL DEFAULT 15 pthread_rwlock_wrlock@@GLIBC_2.34
2571: 000000000009b1a0 878 FUNC GLOBAL DEFAULT 15 pthread_rwlock_wrlock@GLIBC_2.2.5
There are two pthread_rwlock_wrlock symbols in libc.so .dynsym section.
The one with @@ is the default version, the other is hidden.
Note that the version info is stored in .gnu.version and .gnu.version_d
sections of libc and the two symbols are at the _same_ offset.
Currently, specify `pthread_rwlock_wrlock`, `pthread_rwlock_wrlock@@GLIBC_2.34`
or `pthread_rwlock_wrlock@GLIBC_2.2.5` in bpf_uprobe_opts::func_name won't work.
Because there are two `pthread_rwlock_wrlock` in .dynsym sections without the
version suffix and both are global bind.
We could solve this by introducing symbol versioning ([0]). So that users can
specify func, func@LIB_VERSION or func@@LIB_VERSION to attach a uprobe.
This patchset resolves symbol conflicts and add symbol versioning for uprobe.
- Patch 1 resolves symbol conflicts at the same offset
- Patch 2 adds symbol versioning for dynsym
- Patch 3 adds selftests for the above changes
Changes from v3:
- Address comments from Andrii
Changes from v2:
- Add uretprobe selfttest (Alan)
- Check symbol exact match (Alan)
- Fix typo (Jiri)
Changes from v1:
- Address comments from Alan and Jiri
- Add selftests (Someone reminds me that there is an attempt at [1]
and part of the selftest code from Andrii is taken from there)
[0]: https://refspecs.linuxfoundation.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/symversion.html
[1]: https://lore.kernel.org/lkml/CAEf4BzZTrjjyyOm3ak9JsssPSh6T_ZmGd677a2rt5e5rBLUrpQ@mail.gmail.com/
====================
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
This exercises the newly added dynsym symbol versioning logics.
Now we accept symbols in form of func, func@LIB_VERSION or
func@@LIB_VERSION.
The test rely on liburandom_read.so. For liburandom_read.so, we have:
$ nm -D liburandom_read.so
w __cxa_finalize@GLIBC_2.17
w __gmon_start__
w _ITM_deregisterTMCloneTable
w _ITM_registerTMCloneTable
0000000000000000 A LIBURANDOM_READ_1.0.0
0000000000000000 A LIBURANDOM_READ_2.0.0
000000000000081c T urandlib_api@@LIBURANDOM_READ_2.0.0
0000000000000814 T urandlib_api@LIBURANDOM_READ_1.0.0
0000000000000824 T urandlib_api_sameoffset@LIBURANDOM_READ_1.0.0
0000000000000824 T urandlib_api_sameoffset@@LIBURANDOM_READ_2.0.0
000000000000082c T urandlib_read_without_sema@@LIBURANDOM_READ_1.0.0
00000000000007c4 T urandlib_read_with_sema@@LIBURANDOM_READ_1.0.0
0000000000011018 D urandlib_read_with_sema_semaphore@@LIBURANDOM_READ_1.0.0
For `urandlib_api`, specifying `urandlib_api` will cause a conflict because
there are two symbols named urandlib_api and both are global bind.
For `urandlib_api_sameoffset`, there are also two symbols in the .so, but
both are at the same offset and essentially they refer to the same function
so no conflict.
Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20230918024813.237475-4-hengqi.chen@gmail.com
