Bugzilla: https://bugzilla.redhat.com/2177177
commit 96f341a4751d1939a303c5c526b2ca79ebda075f
Author: Colin Ian King <colin.i.king@gmail.com>
Date: Wed Oct 26 09:16:45 2022 +0100
bpftool: Fix spelling mistake "disasembler" -> "disassembler"
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>
Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
Bugzilla: https://bugzilla.redhat.com/2177177
commit ce4f660862359f2172ff4e3df30e641df5475cf6
Author: Quentin Monnet <quentin@isovalent.com>
Date: Tue Oct 25 16:03:28 2022 +0100
bpftool: Support setting alternative arch for JIT disasm with LLVM
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>
Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
Bugzilla: https://bugzilla.redhat.com/2177177
commit eb9d1acf634baf6401dfb4f67dc895290713a357
Author: Quentin Monnet <quentin@isovalent.com>
Date: Tue Oct 25 16:03:27 2022 +0100
bpftool: Add LLVM as default library for disassembling JIT-ed programs
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>
Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
Bugzilla: https://bugzilla.redhat.com/2177177
commit e1947c750ffe5effa371d7b7bc72043f100f6a93
Author: Quentin Monnet <quentin@isovalent.com>
Date: Tue Oct 25 16:03:26 2022 +0100
bpftool: Refactor disassembler for JIT-ed programs
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>
Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
Bugzilla: https://bugzilla.redhat.com/2177177
commit 55b4de58d0e2aca810ed2b198a0173640300acf8
Author: Quentin Monnet <quentin@isovalent.com>
Date: Tue Oct 25 16:03:23 2022 +0100
bpftool: Remove asserts from JIT disassembler
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>
Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
Bugzilla: https://bugzilla.redhat.com/2177177
commit b3d84af7cdfc079ef86d94f7cf125821559925fa
Author: Quentin Monnet <quentin@isovalent.com>
Date: Tue Oct 25 16:03:22 2022 +0100
bpftool: Define _GNU_SOURCE only once
_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>
Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
Bugzilla: https://bugzilla.redhat.com/2137876
Conflicts: already applied 450a8dcb8c7f8 "bpftool: Remove zlib feature
test from Makefile"
commit 600b7b26c07a070d0153daa76b3806c1e52c9e00
Author: Andres Freund <andres@anarazel.de>
Date: Sun Jul 31 18:38:33 2022 -0700
tools bpftool: Fix compilation error with new binutils
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>
Signed-off-by: Artem Savkov <asavkov@redhat.com>
va_list 'ap' was opened but not closed by va_end() in error case. It should
be closed by va_end() before the return.
Fixes: aa52bcbe0e ("tools: bpftool: Fix json dump crash on powerpc")
Signed-off-by: Gu Shengxian <gushengxian@yulong.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: https://lore.kernel.org/bpf/20210706013543.671114-1-gushengxian507419@gmail.com
Fix bpftool to include libbpf header files with the bpf/ prefix, to be
consistent with external users of the library. Also ensure that all
includes of exported libbpf header files (those that are exported on 'make
install' of the library) use bracketed includes instead of quoted.
To make sure no new files are introduced that doesn't include the bpf/
prefix in its include, remove tools/lib/bpf from the include path entirely,
and use tools/lib instead.
Fixes: 6910d7d386 ("selftests/bpf: Ensure bpf_helper_defs.h are taken from selftests dir")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/157952560684.1683545.4765181397974997027.stgit@toke.dk
Michael reported crash with by bpf program in json mode on powerpc:
# bpftool prog -p dump jited id 14
[{
"name": "0xd00000000a9aa760",
"insns": [{
"pc": "0x0",
"operation": "nop",
"operands": [null
]
},{
"pc": "0x4",
"operation": "nop",
"operands": [null
]
},{
"pc": "0x8",
"operation": "mflr",
Segmentation fault (core dumped)
The code is assuming char pointers in format, which is not always
true at least for powerpc. Fixing this by dumping the whole string
into buffer based on its format.
Please note that libopcodes code does not check return values from
fprintf callback, but as per Jakub suggestion returning -1 on allocation
failure so we do the best effort to propagate the error.
Fixes: 107f041212 ("tools: bpftool: add JSON output for `bpftool prog dump jited *` command")
Reported-by: Michael Petlan <mpetlan@redhat.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Currently bpftool contains a mix of GPL-only and GPL or BSD2
licensed files. Make sure all files are dual licensed under
GPLv2 and BSD-2-Clause.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Roman Gushchin <guro@fb.com>
Acked-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Sean Young <sean@mess.org>
Acked-by: Jiri Benc <jbenc@redhat.com>
Acked-by: David Calavera <david.calavera@gmail.com>
Acked-by: Andrey Ignatov <rdna@fb.com>
Acked-by: Joe Stringer <joe@wand.net.nz>
Acked-by: David Ahern <dsahern@gmail.com>
Acked-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Acked-by: Petar Penkov <ppenkov@stanford.edu>
Acked-by: Sandipan Das <sandipan@linux.ibm.com>
Acked-by: Prashant Bhole <bhole_prashant_q7@lab.ntt.co.jp>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Taeung Song <treeze.taeung@gmail.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
CC: okash.khawaja@gmail.com
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
The getpid() function is called in a couple of places in bpftool to
craft links of the shape "/proc/<pid>/...". Instead, it is possible to
use the "/proc/self/" shortcut, which makes things a bit easier, in
particular in jit_disasm.c.
Do the replacement, and remove the includes of <sys/types.h> from the
relevant files, now we do not use getpid() anymore.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Make it possible to build bpftool without libbfd. libbfd and libopcodes are
typically provided in dev/dbg packages (binutils-dev in debian) which we
usually don't have installed on the fleet machines and we'd like a way to have
bpftool version that works without installing any additional packages.
This excludes support for disassembling jit-ted code and prints an error if
the user tries to use these features.
Tested by:
cat > FEATURES_DUMP.bpftool <<EOF
feature-libbfd=0
feature-disassembler-four-args=1
feature-reallocarray=0
feature-libelf=1
feature-libelf-mmap=1
feature-bpf=1
EOF
FEATURES_DUMP=$PWD/FEATURES_DUMP.bpftool make
ldd bpftool | grep libbfd
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The nfp driver is currently always JITing the BPF for 4 context/thread
mode of the NFP flow processors. Tell this to the disassembler,
otherwise some registers may be incorrectly decoded.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
The current architecture detection method in bpftool is designed for host
case.
For offload case, we can't use the architecture of "bpftool" itself.
Instead, we could call the existing "ifindex_to_name_ns" to get DEVNAME,
then read pci id from /sys/class/dev/DEVNAME/device/vendor, finally we map
vendor id to bfd arch name which will finally be used to select bfd backend
for the disassembler.
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Bpftool build is broken with binutils version 2.29 and later.
The cause is commit 003ca0fd2286 ("Refactor disassembler selection")
in the binutils repo, which changed the disassembler() function
signature.
Fix this by adding a new "feature" to the tools/build/features
infrastructure and make it responsible for decision which
disassembler() function signature to use.
Signed-off-by: Roman Gushchin <guro@fb.com>
Cc: Jakub Kicinski <jakub.kicinski@netronome.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Use PATH_MAX instead of hardcoded array size 256
Signed-off-by: Prashant Bhole <bhole_prashant_q7@lab.ntt.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
Reuse the json_writer API introduced in an earlier commit to make
bpftool able to generate JSON output on `bpftool prog show *` commands.
A new printing function is created to be passed as an argument to the
disassembler.
Similarly to plain output, opcodes are printed on request.
Outputs from sample programs have been successfully tested against a
JSON validator.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a simple tool for querying and updating BPF objects on the system.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Jerome Marchand
Artem Savkov
Gu Shengxian
Jagadeesh Pagadala
Toke Høiland-Jørgensen
Jiri Olsa
Jakub Kicinski
Martin KaFai Lau
Quentin Monnet
Stanislav Fomichev
Jiong Wang
Roman Gushchin
Prashant Bhole