Use the new type-safe wrappers around bpf_obj_get_info_by_fd().
Split the bpf_obj_get_info_by_fd() call in build_btf_type_table() in
two, since knowing the type helps with the Memory Sanitizer.
Improve map_parse_fd_and_info() type safety by using
struct bpf_map_info * instead of void * for info.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20230214231221.249277-4-iii@linux.ibm.com
Thorsten reported build issue with command line that defined extra
HOSTCFLAGS that were not passed into 'prepare' targets, but were
used to build resolve_btfids objects.
This results in build fail when these objects are linked together:
/usr/bin/ld: /build.../tools/bpf/resolve_btfids//libbpf/libbpf.a(libbpf-in.o):
relocation R_X86_64_32 against `.rodata.str1.1' can not be used when making a PIE \
object; recompile with -fPIE
Fixing this by passing HOSTCFLAGS in EXTRA_CFLAGS as part of
HOST_OVERRIDES variable for prepare targets.
[1] https://lore.kernel.org/bpf/f7922132-6645-6316-5675-0ece4197bfff@leemhuis.info/
Fixes: 56a2df7615 ("tools/resolve_btfids: Compile resolve_btfids as host program")
Reported-by: Thorsten Leemhuis <linux@leemhuis.info>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Thorsten Leemhuis <linux@leemhuis.info>
Acked-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/bpf/20230209143735.4112845-1-jolsa@kernel.org
Don't set EXTRA_CFLAGS to HOSTCFLAGS, ensure CROSS_COMPILE isn't
passed through.
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20230202224253.40283-1-irogers@google.com
Making resolve_btfids to be compiled as host program so
we can avoid cross compile issues as reported by Nathan.
Also we no longer need HOST_OVERRIDES for BINARY target,
just for 'prepare' targets.
Fixes: 13e07691a1 ("tools/resolve_btfids: Alter how HOSTCC is forced")
Reported-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/bpf/20230202112839.1131892-1-jolsa@kernel.org
The number of online cpu may be not equal to possible cpu.
"bpftool prog profile" can not create pmu event on possible
but on online cpu.
$ dmidecode -s system-product-name
PowerEdge R620
$ cat /sys/devices/system/cpu/possible
0-47
$ cat /sys/devices/system/cpu/online
0-31
Disable cpu dynamically:
$ echo 0 > /sys/devices/system/cpu/cpuX/online
If one cpu is offline, perf_event_open will return ENODEV.
To fix this issue:
* check value returned and skip offline cpu.
* close pmu_fd immediately on error path, avoid fd leaking.
Fixes: 47c09d6a9f ("bpftool: Introduce "prog profile" command")
Signed-off-by: Tonghao Zhang <tong@infragraf.org>
Cc: Quentin Monnet <quentin@isovalent.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Song Liu <song@kernel.org>
Cc: Yonghong Song <yhs@fb.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: KP Singh <kpsingh@kernel.org>
Cc: Stanislav Fomichev <sdf@google.com>
Cc: Hao Luo <haoluo@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/r/20230202131701.29519-1-tong@infragraf.org
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
HOSTCC is always wanted when building. Setting CC to HOSTCC happens
after tools/scripts/Makefile.include is included, meaning flags are
set assuming say CC is gcc, but then it can be later set to HOSTCC
which may be clang. tools/scripts/Makefile.include is needed for host
set up and common macros in objtool's Makefile. Rather than override
CC to HOSTCC, just pass CC as HOSTCC to Makefile.build, the libsubcmd
builds and the linkage step. This means the Makefiles don't see things
like CC changing and tool flag determination, and similar, work
properly.
Also, clear the passed subdir as otherwise an outer build may break by
inadvertently passing an inappropriate value.
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20230124064324.672022-2-irogers@google.com
Previously tools/lib/subcmd was added to the include path, switch to
installing the headers and then including from that directory. This
avoids dependencies on headers internal to tools/lib/subcmd. Add the
missing subcmd directory to the affected #include.
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20230124064324.672022-1-irogers@google.com
When the clang toolchain has stack protection enabled in order to be
consistent with gcc - which just happens to be the case on Gentoo -
the bpftool build fails:
[...]
clang \
-I. \
-I/tmp/portage/dev-util/bpftool-6.0.12/work/linux-6.0/tools/include/uapi/ \
-I/tmp/portage/dev-util/bpftool-6.0.12/work/linux-6.0/tools/bpf/bpftool/bootstrap/libbpf/include \
-g -O2 -Wall -target bpf -c skeleton/pid_iter.bpf.c -o pid_iter.bpf.o
clang \
-I. \
-I/tmp/portage/dev-util/bpftool-6.0.12/work/linux-6.0/tools/include/uapi/ \
-I/tmp/portage/dev-util/bpftool-6.0.12/work/linux-6.0/tools/bpf/bpftool/bootstrap/libbpf/include \
-g -O2 -Wall -target bpf -c skeleton/profiler.bpf.c -o profiler.bpf.o
skeleton/profiler.bpf.c:40:14: error: A call to built-in function '__stack_chk_fail' is not supported.
int BPF_PROG(fentry_XXX)
^
skeleton/profiler.bpf.c:94:14: error: A call to built-in function '__stack_chk_fail' is not supported.
int BPF_PROG(fexit_XXX)
^
2 errors generated.
[...]
Since stack-protector makes no sense for the BPF bits just unconditionally
disable it.
Bug: https://bugs.gentoo.org/890638
Signed-off-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/74cd9d2e-6052-312a-241e-2b514a75c92c@applied-asynchrony.com
When bpftool feature does not find kernel config
files under default path or wrong format,
do not output CONFIG_XYZ is not set.
Skip kernel config check and continue.
Signed-off-by: Chethan Suresh <chethan.suresh@sony.com>
Signed-off-by: Kenta Tada <Kenta.Tada@sony.com>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/r/20230109023742.29657-1-chethan.suresh@sony.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
When passing compiler variables like CC=$(HOSTCC) to a submake
we must ensure the variable is quoted in order to handle cases
where $(HOSTCC) may be multiple binaries.
For example when using ccache $HOSTCC may be:
"/usr/bin/ccache /usr/bin/gcc"
If we pass CC without quotes like CC=$(HOSTCC) only the first
"/usr/bin/ccache" part will be assigned to the CC variable which
will cause an error due to dropping the "/usr/bin/gcc" part of
the variable in the submake invocation.
This fixes errors such as:
/usr/bin/ccache: invalid option -- 'd'
Signed-off-by: James Hilliard <james.hilliard1@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20230110014504.3120711-1-james.hilliard1@gmail.com
Since the commit eb9d1acf63 ("bpftool: Add LLVM as default library for
disassembling JIT-ed programs") we might link the bpftool program with the
libllvm library. This works fine when a shared libllvm library is available,
but fails if we want to link bpftool with a statically built LLVM:
[...]
/usr/bin/ld: /usr/local/lib/libLLVMSupport.a(CrashRecoveryContext.cpp.o): in function `llvm::CrashRecoveryContextCleanup::~CrashRecoveryContextCleanup()':
CrashRecoveryContext.cpp:(.text._ZN4llvm27CrashRecoveryContextCleanupD0Ev+0x17): undefined reference to `operator delete(void*, unsigned long)'
/usr/bin/ld: /usr/local/lib/libLLVMSupport.a(CrashRecoveryContext.cpp.o): in function `llvm::CrashRecoveryContext::~CrashRecoveryContext()':
CrashRecoveryContext.cpp:(.text._ZN4llvm20CrashRecoveryContextD2Ev+0xc8): undefined reference to `operator delete(void*, unsigned long)'
[...]
So in the case of static libllvm we need to explicitly link bpftool with
required libraries, namely, libstdc++ and those provided by the `llvm-config
--system-libs` command. We can distinguish between the shared and static cases
by using the `llvm-config --shared-mode` command.
Fixes: eb9d1acf63 ("bpftool: Add LLVM as default library for disassembling JIT-ed programs")
Signed-off-by: Anton Protopopov <aspsk@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20221222102627.1643709-1-aspsk@isovalent.com
Remove the empty vmlinux.h if bpftool failed to dump btf info.
The empty vmlinux.h can hide real error when reading output
of make.
This is done by adding .DELETE_ON_ERROR special target in related
makefiles.
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20221217223509.88254-3-changbin.du@gmail.com
When libelf was not installed in the standard location, it cannot be
located by the current building config.
Use pkg-config to help locate libelf in such cases.
Signed-off-by: Shen Jiamin <shen_jiamin@comp.nus.edu.sg>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20221215044703.400139-1-shen_jiamin@comp.nus.edu.sg
strdup() allocates memory for path. We need to release the memory in the
following error path. Add free() to avoid memory leak.
Fixes: 8f184732b6 ("bpftool: Switch to libbpf's hashmap for pinned paths of BPF objects")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20221206071906.806384-1-linmq006@gmail.com
The function contains a single btf__free() call which can be
inlined. Credits to Yonghong Song.
Signed-off-by: Sahid Orentino Ferdjaoui <sahid.ferdjaoui@industrialdiscipline.com>
Acked-by: Yonghong Song <yhs@fb.com>
Suggested-by: Yonghong Song <yhs@fb.com>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/r/20221120112515.38165-6-sahid.ferdjaoui@industrialdiscipline.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
bpftool is now totally compliant with libbpf 1.0 mode and is not
expected to be compiled with pre-1.0, let's clean-up the usage of
libbpf_get_error().
The changes stay aligned with returned errors always negative.
- In tools/bpf/bpftool/btf.c This fixes an uninitialized local
variable `err` in function do_dump() because it may now be returned
without having been set.
- This also removes the checks on NULL pointers before calling
btf__free() because that function already does the check.
Signed-off-by: Sahid Orentino Ferdjaoui <sahid.ferdjaoui@industrialdiscipline.com>
Link: https://lore.kernel.org/r/20221120112515.38165-5-sahid.ferdjaoui@industrialdiscipline.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
It is expected that errno be passed to strerror(). This also cleans
this part of code from using libbpf_get_error().
Signed-off-by: Sahid Orentino Ferdjaoui <sahid.ferdjaoui@industrialdiscipline.com>
Acked-by: Yonghong Song <yhs@fb.com>
Suggested-by: Quentin Monnet <quentin@isovalent.com>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/r/20221120112515.38165-4-sahid.ferdjaoui@industrialdiscipline.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
There is no reasons to keep PTR_ERR() when kern_btf=NULL, let's just
return 0.
This also cleans this part of code from using libbpf_get_error().
Signed-off-by: Sahid Orentino Ferdjaoui <sahid.ferdjaoui@industrialdiscipline.com>
Acked-by: Yonghong Song <yhs@fb.com>
Suggested-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/r/20221120112515.38165-3-sahid.ferdjaoui@industrialdiscipline.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
If the parameters for batch are more than 2, check argc first can
return immediately, no need to use is_prefix() to check "file" with
a little overhead and then check argc, it is better to check "file"
only when the parameters for batch are 2.
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Acked-by: Stanislav Fomichev <sdf@google.com>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/r/1668517207-11822-1-git-send-email-yangtiezhu@loongson.cn
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Andrii Nakryiko says:
====================
bpf-next 2022-11-11
We've added 49 non-merge commits during the last 9 day(s) which contain
a total of 68 files changed, 3592 insertions(+), 1371 deletions(-).
The main changes are:
1) Veristat tool improvements to support custom filtering, sorting, and replay
of results, from Andrii Nakryiko.
2) BPF verifier precision tracking fixes and improvements,
from Andrii Nakryiko.
3) Lots of new BPF documentation for various BPF maps, from Dave Tucker,
Donald Hunter, Maryam Tahhan, Bagas Sanjaya.
4) BTF dedup improvements and libbpf's hashmap interface clean ups, from
Eduard Zingerman.
5) Fix veth driver panic if XDP program is attached before veth_open, from
John Fastabend.
6) BPF verifier clean ups and fixes in preparation for follow up features,
from Kumar Kartikeya Dwivedi.
7) Add access to hwtstamp field from BPF sockops programs,
from Martin KaFai Lau.
8) Various fixes for BPF selftests and samples, from Artem Savkov,
Domenico Cerasuolo, Kang Minchul, Rong Tao, Yang Jihong.
9) Fix redirection to tunneling device logic, preventing skb->len == 0, from
Stanislav Fomichev.
* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (49 commits)
selftests/bpf: fix veristat's singular file-or-prog filter
selftests/bpf: Test skops->skb_hwtstamp
selftests/bpf: Fix incorrect ASSERT in the tcp_hdr_options test
bpf: Add hwtstamp field for the sockops prog
selftests/bpf: Fix xdp_synproxy compilation failure in 32-bit arch
bpf, docs: Document BPF_MAP_TYPE_ARRAY
docs/bpf: Document BPF map types QUEUE and STACK
docs/bpf: Document BPF ARRAY_OF_MAPS and HASH_OF_MAPS
docs/bpf: Document BPF_MAP_TYPE_CPUMAP map
docs/bpf: Document BPF_MAP_TYPE_LPM_TRIE map
libbpf: Hashmap.h update to fix build issues using LLVM14
bpf: veth driver panics when xdp prog attached before veth_open
selftests: Fix test group SKIPPED result
selftests/bpf: Tests for btf_dedup_resolve_fwds
libbpf: Resolve unambigous forward declarations
libbpf: Hashmap interface update to allow both long and void* keys/values
samples/bpf: Fix sockex3 error: Missing BPF prog type
selftests/bpf: Fix u32 variable compared with less than zero
Documentation: bpf: Escape underscore in BPF type name prefix
selftests/bpf: Use consistent build-id type for liburandom_read.so
...
====================
Link: https://lore.kernel.org/r/20221111233733.1088228-1-andrii@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
An update for libbpf's hashmap interface from void* -> void* to a
polymorphic one, allowing both long and void* keys and values.
This simplifies many use cases in libbpf as hashmaps there are mostly
integer to integer.
Perf copies hashmap implementation from libbpf and has to be
updated as well.
Changes to libbpf, selftests/bpf and perf are packed as a single
commit to avoid compilation issues with any future bisect.
Polymorphic interface is acheived by hiding hashmap interface
functions behind auxiliary macros that take care of necessary
type casts, for example:
#define hashmap_cast_ptr(p) \
({ \
_Static_assert((p) == NULL || sizeof(*(p)) == sizeof(long),\
#p " pointee should be a long-sized integer or a pointer"); \
(long *)(p); \
})
bool hashmap_find(const struct hashmap *map, long key, long *value);
#define hashmap__find(map, key, value) \
hashmap_find((map), (long)(key), hashmap_cast_ptr(value))
- hashmap__find macro casts key and value parameters to long
and long* respectively
- hashmap_cast_ptr ensures that value pointer points to a memory
of appropriate size.
This hack was suggested by Andrii Nakryiko in [1].
This is a follow up for [2].
[1] https://lore.kernel.org/bpf/CAEf4BzZ8KFneEJxFAaNCCFPGqp20hSpS2aCj76uRk3-qZUH5xg@mail.gmail.com/
[2] https://lore.kernel.org/bpf/af1facf9-7bc8-8a3d-0db4-7b3f333589a2@meta.com/T/#m65b28f1d6d969fcd318b556db6a3ad499a42607d
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20221109142611.879983-2-eddyz87@gmail.com
When using bpftool to pin {PROG, MAP, LINK} without FILE,
segmentation fault will occur. The reson is that the lack
of FILE will cause strlen to trigger NULL pointer dereference.
The corresponding stacktrace is shown below:
do_pin
do_pin_any
do_pin_fd
mount_bpffs_for_pin
strlen(name) <- NULL pointer dereference
Fix it by adding validation to the common process.
Fixes: 75a1e792c3 ("tools: bpftool: Allow all prog/map handles for pinning objects")
Signed-off-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20221102084034.3342995-1-pulehui@huaweicloud.com
There is a spelling mistake in an error message. Fix it.
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/r/20221026081645.3186878-1-colin.i.king@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Add support for new cgroup local storage
Acked-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20221026042901.674177-1-yhs@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Similarly to "libbfd", add a "llvm" feature to the output of command
"bpftool version" to indicate that LLVM is used for disassembling JIT-ed
programs. This feature is mutually exclusive (from Makefile definitions)
with "libbfd".
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Tested-by: Niklas Söderlund <niklas.soderlund@corigine.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20221025150329.97371-9-quentin@isovalent.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
For offloaded BPF programs, instead of failing to create the
LLVM disassembler without even looking for a triple at all, do run the
function that attempts to retrieve a valid architecture name for the
device.
It will still fail for the LLVM disassembler, because currently we have
no valid triple to return (NFP disassembly is not supported by LLVM).
But failing in that function is more logical than to assume in
jit_disasm.c that passing an "arch" name is simply not supported.
Suggested-by: Song Liu <song@kernel.org>
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/r/20221025150329.97371-8-quentin@isovalent.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
To disassemble instructions for JIT-ed programs, bpftool has relied on
the libbfd library. This has been problematic in the past: libbfd's
interface is not meant to be stable and has changed several times. For
building bpftool, we have to detect how the libbfd version on the system
behaves, which is why we have to handle features disassembler-four-args
and disassembler-init-styled in the Makefile. When it comes to shipping
bpftool, this has also caused issues with several distribution
maintainers unwilling to support the feature (see for example Debian's
page for binutils-dev, which ships libbfd: "Note that building Debian
packages which depend on the shared libbfd is Not Allowed." [0]).
For these reasons, we add support for LLVM as an alternative to libbfd
for disassembling instructions of JIT-ed programs. Thanks to the
preparation work in the previous commits, it's easy to add the library
by passing the relevant compilation options in the Makefile, and by
adding the functions for setting up the LLVM disassembler in file
jit_disasm.c.
The LLVM disassembler requires the LLVM development package (usually
llvm-dev or llvm-devel).
The expectation is that the interface for this disassembler will be more
stable. There is a note in LLVM's Developer Policy [1] stating that the
stability for the C API is "best effort" and not guaranteed, but at
least there is some effort to keep compatibility when possible (which
hasn't really been the case for libbfd so far). Furthermore, the Debian
page for the related LLVM package does not caution against linking to
the lib, as binutils-dev page does.
Naturally, the display of disassembled instructions comes with a few
minor differences. Here is a sample output with libbfd (already
supported before this patch):
# bpftool prog dump jited id 56
bpf_prog_6deef7357e7b4530:
0: nopl 0x0(%rax,%rax,1)
5: xchg %ax,%ax
7: push %rbp
8: mov %rsp,%rbp
b: push %rbx
c: push %r13
e: push %r14
10: mov %rdi,%rbx
13: movzwq 0xb4(%rbx),%r13
1b: xor %r14d,%r14d
1e: or $0x2,%r14d
22: mov $0x1,%eax
27: cmp $0x2,%r14
2b: jne 0x000000000000002f
2d: xor %eax,%eax
2f: pop %r14
31: pop %r13
33: pop %rbx
34: leave
35: ret
LLVM supports several variants that we could set when initialising the
disassembler, for example with:
LLVMSetDisasmOptions(*ctx,
LLVMDisassembler_Option_AsmPrinterVariant);
but the default printer is used for now. Here is the output with LLVM:
# bpftool prog dump jited id 56
bpf_prog_6deef7357e7b4530:
0: nopl (%rax,%rax)
5: nop
7: pushq %rbp
8: movq %rsp, %rbp
b: pushq %rbx
c: pushq %r13
e: pushq %r14
10: movq %rdi, %rbx
13: movzwq 180(%rbx), %r13
1b: xorl %r14d, %r14d
1e: orl $2, %r14d
22: movl $1, %eax
27: cmpq $2, %r14
2b: jne 0x2f
2d: xorl %eax, %eax
2f: popq %r14
31: popq %r13
33: popq %rbx
34: leave
35: retq
The LLVM disassembler comes as the default choice, with libbfd as a
fall-back.
Of course, we could replace libbfd entirely and avoid supporting two
different libraries. One reason for keeping libbfd is that, right now,
it works well, we have all we need in terms of features detection in the
Makefile, so it provides a fallback for disassembling JIT-ed programs if
libbfd is installed but LLVM is not. The other motivation is that libbfd
supports nfp instruction for Netronome's SmartNICs and can be used to
disassemble offloaded programs, something that LLVM cannot do. If
libbfd's interface breaks again in the future, we might reconsider
keeping support for it.
[0] https://packages.debian.org/buster/binutils-dev
[1] https://llvm.org/docs/DeveloperPolicy.html#c-api-changes
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Tested-by: Niklas Söderlund <niklas.soderlund@corigine.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20221025150329.97371-7-quentin@isovalent.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Refactor disasm_print_insn() to extract the code specific to libbfd and
move it to dedicated functions. There is no functional change. This is
in preparation for supporting an alternative library for disassembling
the instructions.
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Tested-by: Niklas Söderlund <niklas.soderlund@corigine.com>
Acked-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20221025150329.97371-6-quentin@isovalent.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Bpftool uses libbfd for disassembling JIT-ed programs. But the feature
is optional, and the tool can be compiled without libbfd support. The
Makefile sets the relevant variables accordingly. It also sets variables
related to libbfd's interface, given that it has changed over time.
Group all those libbfd-related definitions so that it's easier to
understand what we are testing for, and only use variables related to
libbfd's interface if we need libbfd in the first place.
In addition to make the Makefile clearer, grouping the definitions
related to disassembling JIT-ed programs will help support alternatives
to libbfd.
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Tested-by: Niklas Söderlund <niklas.soderlund@corigine.com>
Acked-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20221025150329.97371-5-quentin@isovalent.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Make FEATURE_TESTS and FEATURE_DISPLAY easier to read and less likely to
be subject to conflicts on updates by having one feature per line.
Suggested-by: Andres Freund <andres@anarazel.de>
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Tested-by: Niklas Söderlund <niklas.soderlund@corigine.com>
Acked-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20221025150329.97371-4-quentin@isovalent.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The JIT disassembler in bpftool is the only components (with the JSON
writer) using asserts to check the return values of functions. But it
does not do so in a consistent way, and diasm_print_insn() returns no
value, although sometimes the operation failed.
Remove the asserts, and instead check the return values, print messages
on errors, and propagate the error to the caller from prog.c.
Remove the inclusion of assert.h from jit_disasm.c, and also from map.c
where it is unused.
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Tested-by: Niklas Söderlund <niklas.soderlund@corigine.com>
Acked-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20221025150329.97371-3-quentin@isovalent.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
_GNU_SOURCE is defined in several source files for bpftool, but only one
of them takes the precaution of checking whether the value is already
defined. Add #ifndef for other occurrences too.
This is in preparation for the support of disassembling JIT-ed programs
with LLVM, with $(llvm-config --cflags) passing -D_GNU_SOURCE as a
compilation argument.
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Tested-by: Niklas Söderlund <niklas.soderlund@corigine.com>
Acked-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20221025150329.97371-2-quentin@isovalent.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Along with the version number, "bpftool version" displays a list of
features that were selected at compilation time for bpftool. It would be
useful to indicate in that list whether a binary is a bootstrap version
of bpftool. Given that an increasing number of components rely on
bootstrap versions for generating skeletons, this could help understand
what a binary is capable of if it has been copied outside of the usual
"bootstrap" directory.
To detect a bootstrap version, we simply rely on the absence of
implementation for the do_prog() function. To do this, we must move the
(unchanged) list of commands before do_version(), which in turn requires
renaming this "cmds" array to avoid shadowing it with the "cmds"
argument in cmd_select().
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20221020100332.69563-1-quentin@isovalent.com
Commands "bpftool help" or "bpftool version" use argv[0] to display the
name of the binary. While it is a convenient way to retrieve the string,
it does not always produce the most readable output. For example,
because of the way bpftool is currently packaged on Ubuntu (using a
wrapper script), the command displays the absolute path for the binary:
$ bpftool version | head -n 1
/usr/lib/linux-tools/5.15.0-50-generic/bpftool v5.15.60
More generally, there is no apparent reason for keeping the whole path
and exact binary name in this output. If the user wants to understand
what binary is being called, there are other ways to do so. This commit
replaces argv[0] with "bpftool", to simply reflect what the tool is
called. This is aligned on what "ip" or "tc" do, for example.
As an additional benefit, this seems to help with integration with
Meson for packaging [0].
[0] https://github.com/NixOS/nixpkgs/pull/195934
Suggested-by: Vladimír Čunát <vladimir.cunat@nic.cz>
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20221020100300.69328-1-quentin@isovalent.com
strerror() expects a positive errno, however variable err will never be
positive when an error occurs. This causes bpftool to output too many
"unknown error", even a simple "file not exist" error can not get an
accurate message.
This patch fixed all "strerror(err)" patterns in bpftool.
Specially in btf.c#L823, hashmap__append() is an internal function of
libbpf and will not change errno, so there's a little difference.
Some libbpf_get_error() calls are kept for return values.
Changes since v1: https://lore.kernel.org/bpf/SY4P282MB1084B61CD8671DFA395AA8579D539@SY4P282MB1084.AUSP282.PROD.OUTLOOK.COM/
Check directly for NULL values instead of calling libbpf_get_error().
Signed-off-by: Tianyi Liu <i.pear@outlook.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/SY4P282MB1084AD9CD84A920F08DF83E29D549@SY4P282MB1084.AUSP282.PROD.OUTLOOK.COM
After commit 9b190f185d ("tools/bpftool: switch map event_pipe to
libbpf's perf_buffer"), struct event_ring_info is not used any more and
can be removed as well.
Signed-off-by: Yuan Can <yuancan@huawei.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220928090440.79637-3-yuancan@huawei.com
After commit 2828d0d75b ("bpftool: Switch to libbpf's hashmap for
programs/maps in BTF listing"), struct btf_attach_point is not used
anymore and can be removed as well.
Signed-off-by: Yuan Can <yuancan@huawei.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220928090440.79637-2-yuancan@huawei.com
Show tid or pid of iterators if giving an argument of tid or pid
For example, the command `bpftool link list` may list following
lines.
1: iter prog 2 target_name bpf_map
2: iter prog 3 target_name bpf_prog
33: iter prog 225 target_name task_file tid 1644
pids test_progs(1644)
Link 33 is a task_file iterator with tid 1644. For now, only targets
of task, task_file and task_vma may be with tid or pid to filter out
tasks other than those belonging to a process (pid) or a thread (tid).
Signed-off-by: Kui-Feng Lee <kuifeng@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/bpf/20220926184957.208194-6-kuifeng@fb.com
We want to support a ringbuf map type where samples are published from
user-space, to be consumed by BPF programs. BPF currently supports a
kernel -> user-space circular ring buffer via the BPF_MAP_TYPE_RINGBUF
map type. We'll need to define a new map type for user-space -> kernel,
as none of the helpers exported for BPF_MAP_TYPE_RINGBUF will apply
to a user-space producer ring buffer, and we'll want to add one or
more helper functions that would not apply for a kernel-producer
ring buffer.
This patch therefore adds a new BPF_MAP_TYPE_USER_RINGBUF map type
definition. The map type is useless in its current form, as there is no
way to access or use it for anything until we one or more BPF helpers. A
follow-on patch will therefore add a new helper function that allows BPF
programs to run callbacks on samples that are published to the ring
buffer.
Signed-off-by: David Vernet <void@manifault.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220920000100.477320-2-void@manifault.com
When root-cgroup attach multi progs and sub-cgroup attach a override prog,
bpftool will display incorrectly for the attach flags of the sub-cgroup’s
effective progs:
$ bpftool cgroup tree /sys/fs/cgroup effective
CgroupPath
ID AttachType AttachFlags Name
/sys/fs/cgroup
6 cgroup_sysctl multi sysctl_tcp_mem
13 cgroup_sysctl multi sysctl_tcp_mem
/sys/fs/cgroup/cg1
20 cgroup_sysctl override sysctl_tcp_mem
6 cgroup_sysctl override sysctl_tcp_mem <- wrong
13 cgroup_sysctl override sysctl_tcp_mem <- wrong
/sys/fs/cgroup/cg1/cg2
20 cgroup_sysctl sysctl_tcp_mem
6 cgroup_sysctl sysctl_tcp_mem
13 cgroup_sysctl sysctl_tcp_mem
Attach flags is only valid for attached progs of this layer cgroup,
but not for effective progs. For querying with EFFECTIVE flags,
exporting attach flags does not make sense. So let's remove the
AttachFlags field and the associated logic. After this patch, the
above effective cgroup tree will show as bellow:
$ bpftool cgroup tree /sys/fs/cgroup effective
CgroupPath
ID AttachType Name
/sys/fs/cgroup
6 cgroup_sysctl sysctl_tcp_mem
13 cgroup_sysctl sysctl_tcp_mem
/sys/fs/cgroup/cg1
20 cgroup_sysctl sysctl_tcp_mem
6 cgroup_sysctl sysctl_tcp_mem
13 cgroup_sysctl sysctl_tcp_mem
/sys/fs/cgroup/cg1/cg2
20 cgroup_sysctl sysctl_tcp_mem
6 cgroup_sysctl sysctl_tcp_mem
13 cgroup_sysctl sysctl_tcp_mem
Fixes: b79c9fc955 ("bpf: implement BPF_PROG_QUERY for BPF_LSM_CGROUP")
Fixes: a98bf57391 ("tools: bpftool: add support for reporting the effective cgroup progs")
Signed-off-by: Pu Lehui <pulehui@huawei.com>
Link: https://lore.kernel.org/r/20220921104604.2340580-3-pulehui@huaweicloud.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Daniel Borkmann says:
====================
pull-request: bpf-next 2022-09-05
The following pull-request contains BPF updates for your *net-next* tree.
We've added 106 non-merge commits during the last 18 day(s) which contain
a total of 159 files changed, 5225 insertions(+), 1358 deletions(-).
There are two small merge conflicts, resolve them as follows:
1) tools/testing/selftests/bpf/DENYLIST.s390x
Commit 27e23836ce ("selftests/bpf: Add lru_bug to s390x deny list") in
bpf tree was needed to get BPF CI green on s390x, but it conflicted with
newly added tests on bpf-next. Resolve by adding both hunks, result:
[...]
lru_bug # prog 'printk': failed to auto-attach: -524
setget_sockopt # attach unexpected error: -524 (trampoline)
cb_refs # expected error message unexpected error: -524 (trampoline)
cgroup_hierarchical_stats # JIT does not support calling kernel function (kfunc)
htab_update # failed to attach: ERROR: strerror_r(-524)=22 (trampoline)
[...]
2) net/core/filter.c
Commit 1227c1771d ("net: Fix data-races around sysctl_[rw]mem_(max|default).")
from net tree conflicts with commit 29003875bd ("bpf: Change bpf_setsockopt(SOL_SOCKET)
to reuse sk_setsockopt()") from bpf-next tree. Take the code as it is from
bpf-next tree, result:
[...]
if (getopt) {
if (optname == SO_BINDTODEVICE)
return -EINVAL;
return sk_getsockopt(sk, SOL_SOCKET, optname,
KERNEL_SOCKPTR(optval),
KERNEL_SOCKPTR(optlen));
}
return sk_setsockopt(sk, SOL_SOCKET, optname,
KERNEL_SOCKPTR(optval), *optlen);
[...]
The main changes are:
1) Add any-context BPF specific memory allocator which is useful in particular for BPF
tracing with bonus of performance equal to full prealloc, from Alexei Starovoitov.
2) Big batch to remove duplicated code from bpf_{get,set}sockopt() helpers as an effort
to reuse the existing core socket code as much as possible, from Martin KaFai Lau.
3) Extend BPF flow dissector for BPF programs to just augment the in-kernel dissector
with custom logic. In other words, allow for partial replacement, from Shmulik Ladkani.
4) Add a new cgroup iterator to BPF with different traversal options, from Hao Luo.
5) Support for BPF to collect hierarchical cgroup statistics efficiently through BPF
integration with the rstat framework, from Yosry Ahmed.
6) Support bpf_{g,s}et_retval() under more BPF cgroup hooks, from Stanislav Fomichev.
7) BPF hash table and local storages fixes under fully preemptible kernel, from Hou Tao.
8) Add various improvements to BPF selftests and libbpf for compilation with gcc BPF
backend, from James Hilliard.
9) Fix verifier helper permissions and reference state management for synchronous
callbacks, from Kumar Kartikeya Dwivedi.
10) Add support for BPF selftest's xskxceiver to also be used against real devices that
support MAC loopback, from Maciej Fijalkowski.
11) Various fixes to the bpf-helpers(7) man page generation script, from Quentin Monnet.
12) Document BPF verifier's tnum_in(tnum_range(), ...) gotchas, from Shung-Hsi Yu.
13) Various minor misc improvements all over the place.
* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (106 commits)
bpf: Optimize rcu_barrier usage between hash map and bpf_mem_alloc.
bpf: Remove usage of kmem_cache from bpf_mem_cache.
bpf: Remove prealloc-only restriction for sleepable bpf programs.
bpf: Prepare bpf_mem_alloc to be used by sleepable bpf programs.
bpf: Remove tracing program restriction on map types
bpf: Convert percpu hash map to per-cpu bpf_mem_alloc.
bpf: Add percpu allocation support to bpf_mem_alloc.
bpf: Batch call_rcu callbacks instead of SLAB_TYPESAFE_BY_RCU.
bpf: Adjust low/high watermarks in bpf_mem_cache
bpf: Optimize call_rcu in non-preallocated hash map.
bpf: Optimize element count in non-preallocated hash map.
bpf: Relax the requirement to use preallocated hash maps in tracing progs.
samples/bpf: Reduce syscall overhead in map_perf_test.
selftests/bpf: Improve test coverage of test_maps
bpf: Convert hash map to bpf_mem_alloc.
bpf: Introduce any context BPF specific memory allocator.
selftest/bpf: Add test for bpf_getsockopt()
bpf: Change bpf_getsockopt(SOL_IPV6) to reuse do_ipv6_getsockopt()
bpf: Change bpf_getsockopt(SOL_IP) to reuse do_ip_getsockopt()
bpf: Change bpf_getsockopt(SOL_TCP) to reuse do_tcp_getsockopt()
...
====================
Link: https://lore.kernel.org/r/20220905161136.9150-1-daniel@iogearbox.net
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Support dumping info of a cgroup_iter link. This includes
showing the cgroup's id and the order for walking the cgroup
hierarchy. Example output is as follows:
> bpftool link show
1: iter prog 2 target_name bpf_map
2: iter prog 3 target_name bpf_prog
3: iter prog 12 target_name cgroup cgroup_id 72 order self_only
> bpftool -p link show
[{
"id": 1,
"type": "iter",
"prog_id": 2,
"target_name": "bpf_map"
},{
"id": 2,
"type": "iter",
"prog_id": 3,
"target_name": "bpf_prog"
},{
"id": 3,
"type": "iter",
"prog_id": 12,
"target_name": "cgroup",
"cgroup_id": 72,
"order": "self_only"
}
]
Signed-off-by: Hao Luo <haoluo@google.com>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20220829231828.1016835-1-haoluo@google.com
Signed-off-by: Martin KaFai Lau <martin.lau@linux.dev>
When `data` points to a boolean value, casting it to `int *` is problematic
and could lead to a wrong value being passed to `jsonw_bool`. Change the
cast to `bool *` instead.
Fixes: b12d6ec097 ("bpf: btf: add btf print functionality")
Signed-off-by: Lam Thai <lamthai@arista.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20220824225859.9038-1-lamthai@arista.com
Andrii Nakryiko says:
====================
bpf-next 2022-08-17
We've added 45 non-merge commits during the last 14 day(s) which contain
a total of 61 files changed, 986 insertions(+), 372 deletions(-).
The main changes are:
1) New bpf_ktime_get_tai_ns() BPF helper to access CLOCK_TAI, from Kurt
Kanzenbach and Jesper Dangaard Brouer.
2) Few clean ups and improvements for libbpf 1.0, from Andrii Nakryiko.
3) Expose crash_kexec() as kfunc for BPF programs, from Artem Savkov.
4) Add ability to define sleepable-only kfuncs, from Benjamin Tissoires.
5) Teach libbpf's bpf_prog_load() and bpf_map_create() to gracefully handle
unsupported names on old kernels, from Hangbin Liu.
6) Allow opting out from auto-attaching BPF programs by libbpf's BPF skeleton,
from Hao Luo.
7) Relax libbpf's requirement for shared libs to be marked executable, from
Henqgi Chen.
8) Improve bpf_iter internals handling of error returns, from Hao Luo.
9) Few accommodations in libbpf to support GCC-BPF quirks, from James Hilliard.
10) Fix BPF verifier logic around tracking dynptr ref_obj_id, from Joanne Koong.
11) bpftool improvements to handle full BPF program names better, from Manu
Bretelle.
12) bpftool fixes around libcap use, from Quentin Monnet.
13) BPF map internals clean ups and improvements around memory allocations,
from Yafang Shao.
14) Allow to use cgroup_get_from_file() on cgroupv1, allowing BPF cgroup
iterator to work on cgroupv1, from Yosry Ahmed.
15) BPF verifier internal clean ups, from Dave Marchevsky and Joanne Koong.
16) Various fixes and clean ups for selftests/bpf and vmtest.sh, from Daniel
Xu, Artem Savkov, Joanne Koong, Andrii Nakryiko, Shibin Koikkara Reeny.
* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (45 commits)
selftests/bpf: Few fixes for selftests/bpf built in release mode
libbpf: Clean up deprecated and legacy aliases
libbpf: Streamline bpf_attr and perf_event_attr initialization
libbpf: Fix potential NULL dereference when parsing ELF
selftests/bpf: Tests libbpf autoattach APIs
libbpf: Allows disabling auto attach
selftests/bpf: Fix attach point for non-x86 arches in test_progs/lsm
libbpf: Making bpf_prog_load() ignore name if kernel doesn't support
selftests/bpf: Update CI kconfig
selftests/bpf: Add connmark read test
selftests/bpf: Add existing connection bpf_*_ct_lookup() test
bpftool: Clear errno after libcap's checks
bpf: Clear up confusion in bpf_skb_adjust_room()'s documentation
bpftool: Fix a typo in a comment
libbpf: Add names for auxiliary maps
bpf: Use bpf_map_area_alloc consistently on bpf map creation
bpf: Make __GFP_NOWARN consistent in bpf map creation
bpf: Use bpf_map_area_free instread of kvfree
bpf: Remove unneeded memset in queue_stack_map creation
libbpf: preserve errno across pr_warn/pr_info/pr_debug
...
====================
Link: https://lore.kernel.org/r/20220817215656.1180215-1-andrii@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When bpftool is linked against libcap, the library runs a "constructor"
function to compute the number of capabilities of the running kernel
[0], at the beginning of the execution of the program. As part of this,
it performs multiple calls to prctl(). Some of these may fail, and set
errno to a non-zero value:
# strace -e prctl ./bpftool version
prctl(PR_CAPBSET_READ, CAP_MAC_OVERRIDE) = 1
prctl(PR_CAPBSET_READ, 0x30 /* CAP_??? */) = -1 EINVAL (Invalid argument)
prctl(PR_CAPBSET_READ, CAP_CHECKPOINT_RESTORE) = 1
prctl(PR_CAPBSET_READ, 0x2c /* CAP_??? */) = -1 EINVAL (Invalid argument)
prctl(PR_CAPBSET_READ, 0x2a /* CAP_??? */) = -1 EINVAL (Invalid argument)
prctl(PR_CAPBSET_READ, 0x29 /* CAP_??? */) = -1 EINVAL (Invalid argument)
** fprintf added at the top of main(): we have errno == 1
./bpftool v7.0.0
using libbpf v1.0
features: libbfd, libbpf_strict, skeletons
+++ exited with 0 +++
This has been addressed in libcap 2.63 [1], but until this version is
available everywhere, we can fix it on bpftool side.
Let's clean errno at the beginning of the main() function, to make sure
that these checks do not interfere with the batch mode, where we error
out if errno is set after a bpftool command.
[0] https://git.kernel.org/pub/scm/libs/libcap/libcap.git/tree/libcap/cap_alloc.c?h=libcap-2.65#n20
[1] https://git.kernel.org/pub/scm/libs/libcap/libcap.git/commit/?id=f25a1b7e69f7b33e6afb58b3e38f3450b7d2d9a0
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220815162205.45043-1-quentin@isovalent.com
Commit 6e8ccb4f62 ("tools/bpf: properly account for libbfd variations")
sets the linking flags depending on which flavor of the libbfd feature was
detected.
However, the flavors except libbfd cannot be detected, as they are not in
the feature list.
Complete the list of features to detect by adding libbfd-liberty and
libbfd-liberty-z.
Committer notes:
Adjust conflict with with:
1e1613f64c ("tools bpftool: Don't display disassembler-four-args feature test")
600b7b26c0 ("tools bpftool: Fix compilation error with new binutils")
Fixes: 6e8ccb4f62 ("tools/bpf: properly account for libbfd variations")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andres Freund <andres@anarazel.de>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: bpf@vger.kernel.org
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: KP Singh <kpsingh@kernel.org>
Cc: llvm@lists.linux.dev
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Nick Terrell <terrelln@fb.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Monnet <quentin@isovalent.com>
Cc: Song Liu <song@kernel.org>
Cc: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20220719170555.2576993-2-roberto.sassu@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
- Introduce 'perf lock contention' subtool, using new lock contention
tracepoints and using BPF for in kernel aggregation and then userspace
processing using the perf tooling infrastructure for resolving symbols, target
specification, etc.
Since the new lock contention tracepoints don't provide lock names, get up to
8 stack traces and display the first non-lock function symbol name as a caller:
$ perf lock report -F acquired,contended,avg_wait,wait_total
Name acquired contended avg wait total wait
update_blocked_a... 40 40 3.61 us 144.45 us
kernfs_fop_open+... 5 5 3.64 us 18.18 us
_nohz_idle_balance 3 3 2.65 us 7.95 us
tick_do_update_j... 1 1 6.04 us 6.04 us
ep_scan_ready_list 1 1 3.93 us 3.93 us
Supports the usual 'perf record' + 'perf report' workflow as well as a
BCC/bpftrace like mode where you start the tool and then press control+C to get
results:
$ sudo perf lock contention -b
^C
contended total wait max wait avg wait type caller
42 192.67 us 13.64 us 4.59 us spinlock queue_work_on+0x20
23 85.54 us 10.28 us 3.72 us spinlock worker_thread+0x14a
6 13.92 us 6.51 us 2.32 us mutex kernfs_iop_permission+0x30
3 11.59 us 10.04 us 3.86 us mutex kernfs_dop_revalidate+0x3c
1 7.52 us 7.52 us 7.52 us spinlock kthread+0x115
1 7.24 us 7.24 us 7.24 us rwlock:W sys_epoll_wait+0x148
2 7.08 us 3.99 us 3.54 us spinlock delayed_work_timer_fn+0x1b
1 6.41 us 6.41 us 6.41 us spinlock idle_balance+0xa06
2 2.50 us 1.83 us 1.25 us mutex kernfs_iop_lookup+0x2f
1 1.71 us 1.71 us 1.71 us mutex kernfs_iop_getattr+0x2c
...
- Add new 'perf kwork' tool to trace time properties of kernel work (such as
softirq, and workqueue), uses eBPF skeletons to collect info in kernel space,
aggregating data that then gets processed by the userspace tool, e.g.:
# perf kwork report
Kwork Name | Cpu | Total Runtime | Count | Max runtime | Max runtime start | Max runtime end |
----------------------------------------------------------------------------------------------------
nvme0q5:130 | 004 | 1.101 ms | 49 | 0.051 ms | 26035.056403 s | 26035.056455 s |
amdgpu:162 | 002 | 0.176 ms | 9 | 0.046 ms | 26035.268020 s | 26035.268066 s |
nvme0q24:149 | 023 | 0.161 ms | 55 | 0.009 ms | 26035.655280 s | 26035.655288 s |
nvme0q20:145 | 019 | 0.090 ms | 33 | 0.014 ms | 26035.939018 s | 26035.939032 s |
nvme0q31:156 | 030 | 0.075 ms | 21 | 0.010 ms | 26035.052237 s | 26035.052247 s |
nvme0q8:133 | 007 | 0.062 ms | 12 | 0.021 ms | 26035.416840 s | 26035.416861 s |
nvme0q6:131 | 005 | 0.054 ms | 22 | 0.010 ms | 26035.199919 s | 26035.199929 s |
nvme0q19:144 | 018 | 0.052 ms | 14 | 0.010 ms | 26035.110615 s | 26035.110625 s |
nvme0q7:132 | 006 | 0.049 ms | 13 | 0.007 ms | 26035.125180 s | 26035.125187 s |
nvme0q18:143 | 017 | 0.033 ms | 14 | 0.007 ms | 26035.169698 s | 26035.169705 s |
nvme0q17:142 | 016 | 0.013 ms | 1 | 0.013 ms | 26035.565147 s | 26035.565160 s |
enp5s0-rx-0:164 | 006 | 0.004 ms | 4 | 0.002 ms | 26035.928882 s | 26035.928884 s |
enp5s0-tx-0:166 | 008 | 0.003 ms | 3 | 0.002 ms | 26035.870923 s | 26035.870925 s |
--------------------------------------------------------------------------------------------------------
See commit log messages for more examples with extra options to limit the events time window, etc.
- Add support for new AMD IBS (Instruction Based Sampling) features:
With the DataSrc extensions, the source of data can be decoded among:
- Local L3 or other L1/L2 in CCX.
- A peer cache in a near CCX.
- Data returned from DRAM.
- A peer cache in a far CCX.
- DRAM address map with "long latency" bit set.
- Data returned from MMIO/Config/PCI/APIC.
- Extension Memory (S-Link, GenZ, etc - identified by the CS target
and/or address map at DF's choice).
- Peer Agent Memory.
- Support hardware tracing with Intel PT on guest machines, combining the
traces with the ones in the host machine.
- Add a "-m" option to 'perf buildid-list' to show kernel and modules
build-ids, to display all of the information needed to do external
symbolization of kernel stack traces, such as those collected by
bpf_get_stackid().
- Add arch TSC frequency information to perf.data file headers.
- Handle changes in the binutils disassembler function signatures in
perf, bpftool and bpf_jit_disasm (Acked by the bpftool maintainer).
- Fix building the perf perl binding with the newest gcc in distros such
as fedora rawhide, where some new warnings were breaking the build as
perf uses -Werror.
- Add 'perf test' entry for branch stack sampling.
- Add ARM SPE system wide 'perf test' entry.
- Add user space counter reading tests to 'perf test'.
- Build with python3 by default, if available.
- Add python converter script for the vendor JSON event files.
- Update vendor JSON files for alderlake, bonnell, broadwell, broadwellde,
broadwellx, cascadelakex, elkhartlake, goldmont, goldmontplus, haswell,
haswellx, icelake, icelakex, ivybridge, ivytown, jaketown, knightslanding,
nehalemep, nehalemex, sandybridge, sapphirerapids, silvermont, skylake,
skylakex, snowridgex, tigerlake, westmereep-dp, westmereep-sp and westmereex.
- Add vendor JSON File for Intel meteorlake.
- Add Arm Cortex-A78C and X1C JSON vendor event files.
- Add workaround to symbol address reading from ELF files without phdr,
falling back to the previoous equation.
- Convert legacy map definition to BTF-defined in the perf BPF script test.
- Rework prologue generation code to stop using libbpf deprecated APIs.
- Add default hybrid events for 'perf stat' on x86.
- Add topdown metrics in the default 'perf stat' on the hybrid machines (big/little cores).
- Prefer sampled CPU when exporting JSON in 'perf data convert'
- Fix ('perf stat CSV output linter') and ("Check branch stack sampling") 'perf test' entries on s390.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-tools-for-v6.0-2022-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux
Pull perf tools updates from Arnaldo Carvalho de Melo:
- Introduce 'perf lock contention' subtool, using new lock contention
tracepoints and using BPF for in kernel aggregation and then
userspace processing using the perf tooling infrastructure for
resolving symbols, target specification, etc.
Since the new lock contention tracepoints don't provide lock names,
get up to 8 stack traces and display the first non-lock function
symbol name as a caller:
$ perf lock report -F acquired,contended,avg_wait,wait_total
Name acquired contended avg wait total wait
update_blocked_a... 40 40 3.61 us 144.45 us
kernfs_fop_open+... 5 5 3.64 us 18.18 us
_nohz_idle_balance 3 3 2.65 us 7.95 us
tick_do_update_j... 1 1 6.04 us 6.04 us
ep_scan_ready_list 1 1 3.93 us 3.93 us
Supports the usual 'perf record' + 'perf report' workflow as well as
a BCC/bpftrace like mode where you start the tool and then press
control+C to get results:
$ sudo perf lock contention -b
^C
contended total wait max wait avg wait type caller
42 192.67 us 13.64 us 4.59 us spinlock queue_work_on+0x20
23 85.54 us 10.28 us 3.72 us spinlock worker_thread+0x14a
6 13.92 us 6.51 us 2.32 us mutex kernfs_iop_permission+0x30
3 11.59 us 10.04 us 3.86 us mutex kernfs_dop_revalidate+0x3c
1 7.52 us 7.52 us 7.52 us spinlock kthread+0x115
1 7.24 us 7.24 us 7.24 us rwlock:W sys_epoll_wait+0x148
2 7.08 us 3.99 us 3.54 us spinlock delayed_work_timer_fn+0x1b
1 6.41 us 6.41 us 6.41 us spinlock idle_balance+0xa06
2 2.50 us 1.83 us 1.25 us mutex kernfs_iop_lookup+0x2f
1 1.71 us 1.71 us 1.71 us mutex kernfs_iop_getattr+0x2c
...
- Add new 'perf kwork' tool to trace time properties of kernel work
(such as softirq, and workqueue), uses eBPF skeletons to collect info
in kernel space, aggregating data that then gets processed by the
userspace tool, e.g.:
# perf kwork report
Kwork Name | Cpu | Total Runtime | Count | Max runtime | Max runtime start | Max runtime end |
----------------------------------------------------------------------------------------------------
nvme0q5:130 | 004 | 1.101 ms | 49 | 0.051 ms | 26035.056403 s | 26035.056455 s |
amdgpu:162 | 002 | 0.176 ms | 9 | 0.046 ms | 26035.268020 s | 26035.268066 s |
nvme0q24:149 | 023 | 0.161 ms | 55 | 0.009 ms | 26035.655280 s | 26035.655288 s |
nvme0q20:145 | 019 | 0.090 ms | 33 | 0.014 ms | 26035.939018 s | 26035.939032 s |
nvme0q31:156 | 030 | 0.075 ms | 21 | 0.010 ms | 26035.052237 s | 26035.052247 s |
nvme0q8:133 | 007 | 0.062 ms | 12 | 0.021 ms | 26035.416840 s | 26035.416861 s |
nvme0q6:131 | 005 | 0.054 ms | 22 | 0.010 ms | 26035.199919 s | 26035.199929 s |
nvme0q19:144 | 018 | 0.052 ms | 14 | 0.010 ms | 26035.110615 s | 26035.110625 s |
nvme0q7:132 | 006 | 0.049 ms | 13 | 0.007 ms | 26035.125180 s | 26035.125187 s |
nvme0q18:143 | 017 | 0.033 ms | 14 | 0.007 ms | 26035.169698 s | 26035.169705 s |
nvme0q17:142 | 016 | 0.013 ms | 1 | 0.013 ms | 26035.565147 s | 26035.565160 s |
enp5s0-rx-0:164 | 006 | 0.004 ms | 4 | 0.002 ms | 26035.928882 s | 26035.928884 s |
enp5s0-tx-0:166 | 008 | 0.003 ms | 3 | 0.002 ms | 26035.870923 s | 26035.870925 s |
--------------------------------------------------------------------------------------------------------
See commit log messages for more examples with extra options to limit
the events time window, etc.
- Add support for new AMD IBS (Instruction Based Sampling) features:
With the DataSrc extensions, the source of data can be decoded among:
- Local L3 or other L1/L2 in CCX.
- A peer cache in a near CCX.
- Data returned from DRAM.
- A peer cache in a far CCX.
- DRAM address map with "long latency" bit set.
- Data returned from MMIO/Config/PCI/APIC.
- Extension Memory (S-Link, GenZ, etc - identified by the CS target
and/or address map at DF's choice).
- Peer Agent Memory.
- Support hardware tracing with Intel PT on guest machines, combining
the traces with the ones in the host machine.
- Add a "-m" option to 'perf buildid-list' to show kernel and modules
build-ids, to display all of the information needed to do external
symbolization of kernel stack traces, such as those collected by
bpf_get_stackid().
- Add arch TSC frequency information to perf.data file headers.
- Handle changes in the binutils disassembler function signatures in
perf, bpftool and bpf_jit_disasm (Acked by the bpftool maintainer).
- Fix building the perf perl binding with the newest gcc in distros
such as fedora rawhide, where some new warnings were breaking the
build as perf uses -Werror.
- Add 'perf test' entry for branch stack sampling.
- Add ARM SPE system wide 'perf test' entry.
- Add user space counter reading tests to 'perf test'.
- Build with python3 by default, if available.
- Add python converter script for the vendor JSON event files.
- Update vendor JSON files for most Intel cores.
- Add vendor JSON File for Intel meteorlake.
- Add Arm Cortex-A78C and X1C JSON vendor event files.
- Add workaround to symbol address reading from ELF files without phdr,
falling back to the previoous equation.
- Convert legacy map definition to BTF-defined in the perf BPF script
test.
- Rework prologue generation code to stop using libbpf deprecated APIs.
- Add default hybrid events for 'perf stat' on x86.
- Add topdown metrics in the default 'perf stat' on the hybrid machines
(big/little cores).
- Prefer sampled CPU when exporting JSON in 'perf data convert'
- Fix ('perf stat CSV output linter') and ("Check branch stack
sampling") 'perf test' entries on s390.
* tag 'perf-tools-for-v6.0-2022-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux: (169 commits)
perf stat: Refactor __run_perf_stat() common code
perf lock: Print the number of lost entries for BPF
perf lock: Add --map-nr-entries option
perf lock: Introduce struct lock_contention
perf scripting python: Do not build fail on deprecation warnings
genelf: Use HAVE_LIBCRYPTO_SUPPORT, not the never defined HAVE_LIBCRYPTO
perf build: Suppress openssl v3 deprecation warnings in libcrypto feature test
perf parse-events: Break out tracepoint and printing
perf parse-events: Don't #define YY_EXTRA_TYPE
tools bpftool: Don't display disassembler-four-args feature test
tools bpftool: Fix compilation error with new binutils
tools bpf_jit_disasm: Don't display disassembler-four-args feature test
tools bpf_jit_disasm: Fix compilation error with new binutils
tools perf: Fix compilation error with new binutils
tools include: add dis-asm-compat.h to handle version differences
tools build: Don't display disassembler-four-args feature test
tools build: Add feature test for init_disassemble_info API changes
perf test: Add ARM SPE system wide test
perf tools: Rework prologue generation code
perf bpf: Convert legacy map definition to BTF-defined
...
bpftool was limiting the length of names to BPF_OBJ_NAME_LEN in prog_parse
fds.
Since commit b662000aff ("bpftool: Adding support for BTF program names")
we can get the full program name from BTF.
This patch removes the restriction of name length when running `bpftool
prog show name ${name}`.
Test:
Tested against some internal program names that were longer than
`BPF_OBJ_NAME_LEN`, here a redacted example of what was ran to test.
# previous behaviour
$ sudo bpftool prog show name some_long_program_name
Error: can't parse name
# with the patch
$ sudo ./bpftool prog show name some_long_program_name
123456789: tracing name some_long_program_name tag taghexa gpl ....
...
...
...
# too long
sudo ./bpftool prog show name $(python3 -c 'print("A"*128)')
Error: can't parse name
# not too long but no match
$ sudo ./bpftool prog show name $(python3 -c 'print("A"*127)')
Signed-off-by: Manu Bretelle <chantr4@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20220801132409.4147849-1-chantr4@gmail.com
binutils changed the signature of init_disassemble_info(), which now causes
compilation to fail for tools/bpf/bpftool/jit_disasm.c, e.g. on debian
unstable.
Relevant binutils commit:
https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=60a3da00bd5407f07
Wire up the feature test and switch to init_disassemble_info_compat(),
which were introduced in prior commits, fixing the compilation failure.
I verified that bpftool can still disassemble bpf programs, both with an
old and new dis-asm.h API. There are no output changes for plain and json
formats. When comparing the output from old binutils (2.35)
to new bintuils with the patch (upstream snapshot) there are a few output
differences, but they are unrelated to this patch. An example hunk is:
2f: pop %r14
31: pop %r13
33: pop %rbx
- 34: leaveq
- 35: retq
+ 34: leave
+ 35: ret
Signed-off-by: Andres Freund <andres@anarazel.de>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Ben Hutchings <benh@debian.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Quentin Monnet <quentin@isovalent.com>
Cc: Sedat Dilek <sedat.dilek@gmail.com>
Cc: bpf@vger.kernel.org
Link: http://lore.kernel.org/lkml/20220622181918.ykrs5rsnmx3og4sv@alap3.anarazel.de
Link: https://lore.kernel.org/r/20220801013834.156015-8-andres@anarazel.de
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
binutils changed the signature of init_disassemble_info(), which now causes
compilation to fail for tools/bpf/bpf_jit_disasm.c, e.g. on debian
unstable.
Relevant binutils commit:
https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=60a3da00bd5407f07
Wire up the feature test and switch to init_disassemble_info_compat(),
which were introduced in prior commits, fixing the compilation failure.
I verified that bpf_jit_disasm can still disassemble bpf programs, both
with the old and new dis-asm.h API. With old binutils there's no change in
output before/after this patch. When comparing the output from old
binutils (2.35) to new bintuils with the patch (upstream snapshot) there
are a few output differences, but they are unrelated to this patch. An
example hunk is:
f4: mov %r14,%rsi
f7: mov %r15,%rdx
fa: mov $0x2a,%ecx
- ff: callq 0xffffffffea8c4988
+ ff: call 0xffffffffea8c4988
104: test %rax,%rax
107: jge 0x0000000000000110
109: xor %eax,%eax
- 10b: jmpq 0x0000000000000073
+ 10b: jmp 0x0000000000000073
110: cmp $0x16,%rax
However, I had to use an older kernel to generate the bpf_jit_enabled =
2 output, as that has been broken since 5.18 / 1022a5498f ("bpf,
x86_64: Use bpf_jit_binary_pack_alloc").
https://lore.kernel.org/20220703030210.pmjft7qc2eajzi6c@alap3.anarazel.de
Signed-off-by: Andres Freund <andres@anarazel.de>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Ben Hutchings <benh@debian.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Quentin Monnet <quentin@isovalent.com>
Cc: Sedat Dilek <sedat.dilek@gmail.com>
Cc: bpf@vger.kernel.org
Link: http://lore.kernel.org/lkml/20220622181918.ykrs5rsnmx3og4sv@alap3.anarazel.de
Link: https://lore.kernel.org/r/20220801013834.156015-6-andres@anarazel.de
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
A skeleton generated by bpftool previously contained a return followed
by an expression in OBJ_NAME__detach(), which has return type void. This
did not hurt, the bpf_object__detach_skeleton() called there returns
void itself anyway, but led to a warning when compiling with e.g.
-pedantic.
Signed-off-by: Jörn-Thorben Hinz <jthinz@mailbox.tu-berlin.de>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20220726133203.514087-1-jthinz@mailbox.tu-berlin.de
Use the ARRAY_SIZE macro and make the code more compact.
Signed-off-by: Rongguang Wei <weirongguang@kylinos.cn>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20220726093045.3374026-1-clementwei90@163.com
A flag is a 4-byte symbol that may follow a BTF ID in a set8. This is
used in the kernel to tag kfuncs in BTF sets with certain flags. Add
support to adjust the sorting code so that it passes size as 8 bytes
for 8-byte BTF sets.
Cc: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20220721134245.2450-3-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
tools/runqslower use bpftool for vmlinux.h, skeleton, and static linking
only. So we can use lightweight bootstrap version of bpftool to handle
these, and it will be faster.
Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220714024612.944071-3-pulehui@huawei.com
The feature test to detect the availability of zlib in bpftool's
Makefile does not bring much. The library is not optional: it may or may
not be required along libbfd for disassembling instructions, but in any
case it is necessary to build feature.o or even libbpf, on which bpftool
depends.
If we remove the feature test, we lose the nicely formatted error
message, but we get a compiler error about "zlib.h: No such file or
directory", which is equally informative. Let's get rid of the test.
Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220705200456.285943-1-quentin@isovalent.com
bpftool needs to know about the newly introduced BPF_CORE_TYPE_MATCHES
relocation for its 'gen min_core_btf' command to work properly in the
present of this relocation.
Specifically, we need to make sure to mark types and fields so that they
are present in the minimized BTF for "type match" checks to work out.
However, contrary to the existing btfgen_record_field_relo, we need to
rely on the BTF -- and not the spec -- to find fields. With this change
we handle this new variant correctly. The functionality will be tested
with follow on changes to BPF selftests, which already run against a
minimized BTF created with bpftool.
Signed-off-by: Daniel Müller <deso@posteo.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20220628160127.607834-3-deso@posteo.net
To make it more explicit that the features listed with "bpftool feature
list" are known to bpftool, but not necessary available on the system
(as opposed to the probed features), rename the "feature list" command
into "feature list_builtins".
Note that "bpftool feature list" still works as before given that we
recognise arguments from their prefixes; but the real name of the
subcommand, in particular as displayed in the man page or the
interactive help, will now include "_builtins".
Since we update the bash completion accordingly, let's also take this
chance to redirect error output to /dev/null in the completion script,
to avoid displaying unexpected error messages when users attempt to
tab-complete.
Suggested-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20220701093805.16920-1-quentin@isovalent.com
For example, /sys/fs/bpf/maps.debug is a BPF link. When you run `bpftool map show`
to show it:
Before:
$ bpftool map show pinned /sys/fs/bpf/maps.debug
Error: incorrect object type: unknown
After:
$ bpftool map show pinned /sys/fs/bpf/maps.debug
Error: incorrect object type: link
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20220629154832.56986-5-laoar.shao@gmail.com
Now that bpftool is able to produce a list of known program, map, attach
types, let's use as much of this as we can in the bash completion file,
so that we don't have to expand the list each time a new type is added
to the kernel.
Also update the relevant test script to remove some checks that are no
longer needed.
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Daniel Müller <deso@posteo.net>
Link: https://lore.kernel.org/bpf/20220629203637.138944-3-quentin@isovalent.com
Add a "bpftool feature list" subcommand to list BPF "features".
Contrarily to "bpftool feature probe", this is not about the features
available on the system. Instead, it lists all features known to bpftool
from compilation time; in other words, all program, map, attach, link
types known to the libbpf version in use, and all helpers found in the
UAPI BPF header.
The first use case for this feature is bash completion: running the
command provides a list of types that can be used to produce the list of
candidate map types, for example.
Now that bpftool uses "standard" names provided by libbpf for the
program, map, link, and attach types, having the ability to list these
types and helpers could also be useful in scripts to loop over existing
items.
Sample output:
# bpftool feature list prog_types | grep -vw unspec | head -n 6
socket_filter
kprobe
sched_cls
sched_act
tracepoint
xdp
# bpftool -p feature list map_types | jq '.[1]'
"hash"
# bpftool feature list attach_types | grep '^cgroup_'
cgroup_inet_ingress
cgroup_inet_egress
[...]
cgroup_inet_sock_release
# bpftool feature list helpers | grep -vw bpf_unspec | wc -l
207
The "unspec" types and helpers are not filtered out by bpftool, so as to
remain closer to the enums, and to preserve the indices in the JSON
arrays (e.g. "hash" at index 1 == BPF_MAP_TYPE_HASH in map types list).
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Daniel Müller <deso@posteo.net>
Link: https://lore.kernel.org/bpf/20220629203637.138944-2-quentin@isovalent.com
The attach_type_name definition was removed in commit 1ba5ad36e0
("bpftool: Use libbpf_bpf_attach_type_str"). Remove its forward
declaration in main.h as well.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20220630093638.25916-1-tklauser@distanz.ch
Bpftool used to bump the memlock rlimit to make sure to be able to load
BPF objects. After the kernel has switched to memcg-based memory
accounting [0] in 5.11, bpftool has relied on libbpf to probe the system
for memcg-based accounting support and for raising the rlimit if
necessary [1]. But this was later reverted, because the probe would
sometimes fail, resulting in bpftool not being able to load all required
objects [2].
Here we add a more efficient probe, in bpftool itself. We first lower
the rlimit to 0, then we attempt to load a BPF object (and finally reset
the rlimit): if the load succeeds, then memcg-based memory accounting is
supported.
This approach was earlier proposed for the probe in libbpf itself [3],
but given that the library may be used in multithreaded applications,
the probe could have undesirable consequences if one thread attempts to
lock kernel memory while memlock rlimit is at 0. Since bpftool is
single-threaded and the rlimit is process-based, this is fine to do in
bpftool itself.
This probe was inspired by the similar one from the cilium/ebpf Go
library [4].
[0] commit 97306be45f ("Merge branch 'switch to memcg-based memory accounting'")
[1] commit a777e18f1b ("bpftool: Use libbpf 1.0 API mode instead of RLIMIT_MEMLOCK")
[2] commit 6b4384ff10 ("Revert "bpftool: Use libbpf 1.0 API mode instead of RLIMIT_MEMLOCK"")
[3] https://lore.kernel.org/bpf/20220609143614.97837-1-quentin@isovalent.com/t/#u
[4] https://github.com/cilium/ebpf/blob/v0.9.0/rlimit/rlimit.go#L39
Suggested-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Yafang Shao <laoar.shao@gmail.com>
Link: https://lore.kernel.org/bpf/20220629111351.47699-1-quentin@isovalent.com
The function always returns 0, so we don't need to check whether the
return value is 0 or not.
This change was first introduced in commit a777e18f1b ("bpftool: Use
libbpf 1.0 API mode instead of RLIMIT_MEMLOCK"), but later reverted to
restore the unconditional rlimit bump in bpftool. Let's re-add it.
Co-developed-by: Yafang Shao <laoar.shao@gmail.com>
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220610112648.29695-3-quentin@isovalent.com
This reverts commit a777e18f1b.
In commit a777e18f1b ("bpftool: Use libbpf 1.0 API mode instead of
RLIMIT_MEMLOCK"), we removed the rlimit bump in bpftool, because the
kernel has switched to memcg-based memory accounting. Thanks to the
LIBBPF_STRICT_AUTO_RLIMIT_MEMLOCK, we attempted to keep compatibility
with other systems and ask libbpf to raise the limit for us if
necessary.
How do we know if memcg-based accounting is supported? There is a probe
in libbpf to check this. But this probe currently relies on the
availability of a given BPF helper, bpf_ktime_get_coarse_ns(), which
landed in the same kernel version as the memory accounting change. This
works in the generic case, but it may fail, for example, if the helper
function has been backported to an older kernel. This has been observed
for Google Cloud's Container-Optimized OS (COS), where the helper is
available but rlimit is still in use. The probe succeeds, the rlimit is
not raised, and probing features with bpftool, for example, fails.
A patch was submitted [0] to update this probe in libbpf, based on what
the cilium/ebpf Go library does [1]. It would lower the soft rlimit to
0, attempt to load a BPF object, and reset the rlimit. But it may induce
some hard-to-debug flakiness if another process starts, or the current
application is killed, while the rlimit is reduced, and the approach was
discarded.
As a workaround to ensure that the rlimit bump does not depend on the
availability of a given helper, we restore the unconditional rlimit bump
in bpftool for now.
[0] https://lore.kernel.org/bpf/20220609143614.97837-1-quentin@isovalent.com/
[1] https://github.com/cilium/ebpf/blob/v0.9.0/rlimit/rlimit.go#L39
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Yafang Shao <laoar.shao@gmail.com>
Cc: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20220610112648.29695-2-quentin@isovalent.com
This change adjusts the Makefile to use "HOSTAR" as the archive tool
to keep the sanity of the build process for the bootstrap part in
check. For the rationale, please continue reading.
When cross compiling bpftool with buildroot, it leads to an invocation
like:
$ AR="/path/to/buildroot/host/bin/arc-linux-gcc-ar" \
CC="/path/to/buildroot/host/bin/arc-linux-gcc" \
...
make
Which in return fails while building the bootstrap section:
----------------------------------8<----------------------------------
make: Entering directory '/src/bpftool-v6.7.0/src'
... libbfd: [ on ]
... disassembler-four-args: [ on ]
... zlib: [ on ]
... libcap: [ OFF ]
... clang-bpf-co-re: [ on ] <-- triggers bootstrap
.
.
.
LINK /src/bpftool-v6.7.0/src/bootstrap/bpftool
/usr/bin/ld: /src/bpftool-v6.7.0/src/bootstrap/libbpf/libbpf.a:
error adding symbols: archive has no index; run ranlib
to add one
collect2: error: ld returned 1 exit status
make: *** [Makefile:211: /src/bpftool-v6.7.0/src/bootstrap/bpftool]
Error 1
make: *** Waiting for unfinished jobs....
AR /src/bpftool-v6.7.0/src/libbpf/libbpf.a
make[1]: Leaving directory '/src/bpftool-v6.7.0/libbpf/src'
make: Leaving directory '/src/bpftool-v6.7.0/src'
---------------------------------->8----------------------------------
This occurs because setting "AR" confuses the build process for the
bootstrap section and it calls "arc-linux-gcc-ar" to create and index
"libbpf.a" instead of the host "ar".
Signed-off-by: Shahab Vahedi <shahab@synopsys.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Cc: Jean-Philippe Brucker <jean-philippe@linaro.org>
Link: https://lore.kernel.org/bpf/8d297f0c-cfd0-ef6f-3970-6dddb3d9a87a@synopsys.com
Add BTF_KIND_ENUM64 support.
For example, the following enum is defined in uapi bpf.h.
$ cat core.c
enum A {
BPF_F_INDEX_MASK = 0xffffffffULL,
BPF_F_CURRENT_CPU = BPF_F_INDEX_MASK,
BPF_F_CTXLEN_MASK = (0xfffffULL << 32),
} g;
Compiled with
clang -target bpf -O2 -g -c core.c
Using bpftool to dump types and generate format C file:
$ bpftool btf dump file core.o
...
[1] ENUM64 'A' encoding=UNSIGNED size=8 vlen=3
'BPF_F_INDEX_MASK' val=4294967295ULL
'BPF_F_CURRENT_CPU' val=4294967295ULL
'BPF_F_CTXLEN_MASK' val=4503595332403200ULL
$ bpftool btf dump file core.o format c
...
enum A {
BPF_F_INDEX_MASK = 4294967295ULL,
BPF_F_CURRENT_CPU = 4294967295ULL,
BPF_F_CTXLEN_MASK = 4503595332403200ULL,
};
...
Note that for raw btf output, the encoding (UNSIGNED or SIGNED)
is printed out as well. The 64bit value is also represented properly
in BTF and C dump.
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20220607062652.3722649-1-yhs@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
bpf_object__btf() can return a NULL value. If bpf_object__btf returns
null, do not progress through codegen_asserts(). This avoids a null ptr
dereference at the call btf__type_cnt() in the function find_type_for_map()
Signed-off-by: Michael Mullin <masmullin@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220523194917.igkgorco42537arb@jup
This change switches bpftool over to using the recently introduced
libbpf_bpf_link_type_str function instead of maintaining its own string
representation for the bpf_link_type enum.
Signed-off-by: Daniel Müller <deso@posteo.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20220523230428.3077108-13-deso@posteo.net
This change switches bpftool over to using the recently introduced
libbpf_bpf_attach_type_str function instead of maintaining its own
string representation for the bpf_attach_type enum.
Note that contrary to other enum types, the variant names that bpftool
maps bpf_attach_type to do not adhere a simple to follow rule. With
bpf_prog_type, for example, the textual representation can easily be
inferred by stripping the BPF_PROG_TYPE_ prefix and lowercasing the
remaining string. bpf_attach_type violates this rule for various
variants.
We decided to fix up this deficiency with this change, meaning that
bpftool uses the same textual representations as libbpf. Supporting
tests, completion scripts, and man pages have been adjusted accordingly.
However, we did add support for accepting (the now undocumented)
original attach type names when they are provided by users.
For the test (test_bpftool_synctypes.py), I have removed the enum
representation checks, because we no longer mirror the various enum
variant names in bpftool source code. For the man page, help text, and
completion script checks we are now using enum definitions from
uapi/linux/bpf.h as the source of truth directly.
Signed-off-by: Daniel Müller <deso@posteo.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20220523230428.3077108-10-deso@posteo.net
This change switches bpftool over to using the recently introduced
libbpf_bpf_map_type_str function instead of maintaining its own string
representation for the bpf_map_type enum.
Signed-off-by: Daniel Müller <deso@posteo.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20220523230428.3077108-7-deso@posteo.net
This change switches bpftool over to using the recently introduced
libbpf_bpf_prog_type_str function instead of maintaining its own string
representation for the bpf_prog_type enum.
Signed-off-by: Daniel Müller <deso@posteo.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20220523230428.3077108-4-deso@posteo.net
Currently, dumping almost all BTFs specified by id requires
using the -B option to pass the base BTF. For kernel module
BTFs the vmlinux BTF sysfs path should work.
This patch simplifies dumping by ID usage by loading
vmlinux BTF from sysfs as base, if base BTF was not specified
and the ID corresponds to a kernel module BTF.
Signed-off-by: Larysa Zaremba <larysa.zaremba@intel.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Alexander Lobakin <alexandr.lobakin@intel.com>
Link: https://lore.kernel.org/bpf/20220513121743.12411-1-larysa.zaremba@intel.com
Replace struct bpf_tramp_progs with struct bpf_tramp_links to collect
struct bpf_tramp_link(s) for a trampoline. struct bpf_tramp_link
extends bpf_link to act as a linked list node.
arch_prepare_bpf_trampoline() accepts a struct bpf_tramp_links to
collects all bpf_tramp_link(s) that a trampoline should call.
Change BPF trampoline and bpf_struct_ops to pass bpf_tramp_links
instead of bpf_tramp_progs.
Signed-off-by: Kui-Feng Lee <kuifeng@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220510205923.3206889-2-kuifeng@fb.com
bpf_link_get_from_fd currently returns a NULL fd for LSM programs.
LSM programs are similar to tracing programs and can also use
skel_raw_tracepoint_open.
Signed-off-by: KP Singh <kpsingh@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220509214905.3754984-1-kpsingh@kernel.org
Currently in libbpf, we have hardcoded program types that are not
supported for helper function probing (e.g. tracing, ext, lsm).
Due to this (and other legitimate failures), bpftool feature probe returns
empty for those program type helper functions.
Instead of implying to the user that there are no helper functions
available for a program type, we output a message to the user explaining
that helper function probing failed for that program type.
Signed-off-by: Milan Landaverde <milan@mdaverde.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220504161356.3497972-3-milan@mdaverde.com
musl nftw implementation does not support FTW_ACTIONRETVAL. There have been
multiple attempts at pushing the feature in musl upstream, but it has been
refused or ignored all the times:
https://www.openwall.com/lists/musl/2021/03/26/1https://www.openwall.com/lists/musl/2022/01/22/1
In this case we only care about /proc/<pid>/fd/<fd>, so it's not too difficult
to reimplement directly instead, and the new implementation makes 'bpftool perf'
slightly faster because it doesn't needlessly stat/readdir unneeded directories
(54ms -> 13ms on my machine).
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20220424051022.2619648-4-asmadeus@codewreck.org
We have switched to memcg-based memory accouting and thus the rlimit is
not needed any more. LIBBPF_STRICT_AUTO_RLIMIT_MEMLOCK was introduced in
libbpf for backward compatibility, so we can use it instead now.
libbpf_set_strict_mode always return 0, so we don't need to check whether
the return value is 0 or not.
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220409125958.92629-4-laoar.shao@gmail.com
Daniel Borkmann says:
====================
pull-request: bpf-next 2022-04-09
We've added 63 non-merge commits during the last 9 day(s) which contain
a total of 68 files changed, 4852 insertions(+), 619 deletions(-).
The main changes are:
1) Add libbpf support for USDT (User Statically-Defined Tracing) probes.
USDTs are an abstraction built on top of uprobes, critical for tracing
and BPF, and widely used in production applications, from Andrii Nakryiko.
2) While Andrii was adding support for x86{-64}-specific logic of parsing
USDT argument specification, Ilya followed-up with USDT support for s390
architecture, from Ilya Leoshkevich.
3) Support name-based attaching for uprobe BPF programs in libbpf. The format
supported is `u[ret]probe/binary_path:[raw_offset|function[+offset]]`, e.g.
attaching to libc malloc can be done in BPF via SEC("uprobe/libc.so.6:malloc")
now, from Alan Maguire.
4) Various load/store optimizations for the arm64 JIT to shrink the image
size by using arm64 str/ldr immediate instructions. Also enable pointer
authentication to verify return address for JITed code, from Xu Kuohai.
5) BPF verifier fixes for write access checks to helper functions, e.g.
rd-only memory from bpf_*_cpu_ptr() must not be passed to helpers that
write into passed buffers, from Kumar Kartikeya Dwivedi.
6) Fix overly excessive stack map allocation for its base map structure and
buckets which slipped-in from cleanups during the rlimit accounting removal
back then, from Yuntao Wang.
7) Extend the unstable CT lookup helpers for XDP and tc/BPF to report netfilter
connection tracking tuple direction, from Lorenzo Bianconi.
8) Improve bpftool dump to show BPF program/link type names, Milan Landaverde.
9) Minor cleanups all over the place from various others.
* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (63 commits)
bpf: Fix excessive memory allocation in stack_map_alloc()
selftests/bpf: Fix return value checks in perf_event_stackmap test
selftests/bpf: Add CO-RE relos into linked_funcs selftests
libbpf: Use weak hidden modifier for USDT BPF-side API functions
libbpf: Don't error out on CO-RE relos for overriden weak subprogs
samples, bpf: Move routes monitor in xdp_router_ipv4 in a dedicated thread
libbpf: Allow WEAK and GLOBAL bindings during BTF fixup
libbpf: Use strlcpy() in path resolution fallback logic
libbpf: Add s390-specific USDT arg spec parsing logic
libbpf: Make BPF-side of USDT support work on big-endian machines
libbpf: Minor style improvements in USDT code
libbpf: Fix use #ifdef instead of #if to avoid compiler warning
libbpf: Potential NULL dereference in usdt_manager_attach_usdt()
selftests/bpf: Uprobe tests should verify param/return values
libbpf: Improve string parsing for uprobe auto-attach
libbpf: Improve library identification for uprobe binary path resolution
selftests/bpf: Test for writes to map key from BPF helpers
selftests/bpf: Test passing rdonly mem to global func
bpf: Reject writes for PTR_TO_MAP_KEY in check_helper_mem_access
bpf: Check PTR_TO_MEM | MEM_RDONLY in check_helper_mem_access
...
====================
Link: https://lore.kernel.org/r/20220408231741.19116-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
In addition to displaying the program type in bpftool prog show
this enables us to be able to query bpf_prog_type_syscall
availability through feature probe as well as see
which helpers are available in those programs (such as
bpf_sys_bpf and bpf_sys_close)
Signed-off-by: Milan Landaverde <milan@mdaverde.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20220331154555.422506-2-milan@mdaverde.com
