Commit Graph

830 Commits

Author SHA1 Message Date
Linus Torvalds
33afd4b763 Mainly singleton patches all over the place. Series of note are:
- updates to scripts/gdb from Glenn Washburn
 
 - kexec cleanups from Bjorn Helgaas
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Merge tag 'mm-nonmm-stable-2023-04-27-16-01' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull non-MM updates from Andrew Morton:
 "Mainly singleton patches all over the place.

  Series of note are:

   - updates to scripts/gdb from Glenn Washburn

   - kexec cleanups from Bjorn Helgaas"

* tag 'mm-nonmm-stable-2023-04-27-16-01' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (50 commits)
  mailmap: add entries for Paul Mackerras
  libgcc: add forward declarations for generic library routines
  mailmap: add entry for Oleksandr
  ocfs2: reduce ioctl stack usage
  fs/proc: add Kthread flag to /proc/$pid/status
  ia64: fix an addr to taddr in huge_pte_offset()
  checkpatch: introduce proper bindings license check
  epoll: rename global epmutex
  scripts/gdb: add GDB convenience functions $lx_dentry_name() and $lx_i_dentry()
  scripts/gdb: create linux/vfs.py for VFS related GDB helpers
  uapi/linux/const.h: prefer ISO-friendly __typeof__
  delayacct: track delays from IRQ/SOFTIRQ
  scripts/gdb: timerlist: convert int chunks to str
  scripts/gdb: print interrupts
  scripts/gdb: raise error with reduced debugging information
  scripts/gdb: add a Radix Tree Parser
  lib/rbtree: use '+' instead of '|' for setting color.
  proc/stat: remove arch_idle_time()
  checkpatch: check for misuse of the link tags
  checkpatch: allow Closes tags with links
  ...
2023-04-27 19:57:00 -07:00
Florian Westphal
d0fe92fb5e tools: bpftool: print netfilter link info
Dump protocol family, hook and priority value:
$ bpftool link
2: netfilter  prog 14
        ip input prio -128
        pids install(3264)
5: netfilter  prog 14
        ip6 forward prio 21
        pids a.out(3387)
9: netfilter  prog 14
        ip prerouting prio 123
        pids a.out(5700)
10: netfilter  prog 14
        ip input prio 21
        pids test2(5701)

v2: Quentin Monnet suggested to also add 'bpftool net' support:

$ bpftool net
xdp:

tc:

flow_dissector:

netfilter:

        ip prerouting prio 21 prog_id 14
        ip input prio -128 prog_id 14
        ip input prio 21 prog_id 14
        ip forward prio 21 prog_id 14
        ip output prio 21 prog_id 14
        ip postrouting prio 21 prog_id 14

'bpftool net' only dumps netfilter link type, links are sorted by protocol
family, hook and priority.

v5: fix bpf ci failure: libbpf needs small update to prog_type_name[]
    and probe_prog_load helper.
v4: don't fail with -EOPNOTSUPP in libbpf probe_prog_load, update
    prog_type_name[] with "netfilter" entry (bpf ci)
v3: fix bpf.h copy, 'reserved' member was removed (Alexei)
    use p_err, not fprintf (Quentin)

Suggested-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/eeeaac99-9053-90c2-aa33-cc1ecb1ae9ca@isovalent.com/
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Link: https://lore.kernel.org/r/20230421170300.24115-6-fw@strlen.de
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-21 11:34:49 -07:00
Kui-Feng Lee
45cea721ea bpftool: Update doc to explain struct_ops register subcommand.
The "struct_ops register" subcommand now allows for an optional *LINK_DIR*
to be included. This specifies the directory path where bpftool will pin
struct_ops links with the same name as their corresponding map names.

Signed-off-by: Kui-Feng Lee <kuifeng@meta.com>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/r/20230420002822.345222-2-kuifeng@meta.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-21 11:10:10 -07:00
Kui-Feng Lee
0232b78897 bpftool: Register struct_ops with a link.
You can include an optional path after specifying the object name for the
'struct_ops register' subcommand.

Since the commit 226bc6ae64 ("Merge branch 'Transit between BPF TCP
congestion controls.'") has been accepted, it is now possible to create a
link for a struct_ops. This can be done by defining a struct_ops in
SEC(".struct_ops.link") to make libbpf returns a real link. If we don't pin
the links before leaving bpftool, they will disappear. To instruct bpftool
to pin the links in a directory with the names of the maps, we need to
provide the path of that directory.

Signed-off-by: Kui-Feng Lee <kuifeng@meta.com>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/r/20230420002822.345222-1-kuifeng@meta.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-21 11:10:10 -07:00
Quentin Monnet
4b7ef71ac9 bpftool: Replace "__fallthrough" by a comment to address merge conflict
The recent support for inline annotations in control flow graphs
generated by bpftool introduced the usage of the "__fallthrough" macro
in a switch/case block in btf_dumper.c. This change went through the
bpf-next tree, but resulted in a merge conflict in linux-next, because
this macro has been renamed "fallthrough" (no underscores) in the
meantime.

To address the conflict, we temporarily switch to a simple comment
instead of a macro.

Related: commit f7a858bffc ("tools: Rename __fallthrough to fallthrough")

Fixes: 9fd496848b ("bpftool: Support inline annotations when dumping the CFG of a program")
Reported-by: Sven Schnelle <svens@linux.ibm.com>
Reported-by: Thomas Richter <tmricht@linux.ibm.com>
Suggested-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/all/yt9dttxlwal7.fsf@linux.ibm.com/
Link: https://lore.kernel.org/bpf/20230412123636.2358949-1-tmricht@linux.ibm.com/
Link: https://lore.kernel.org/bpf/20230420003333.90901-1-quentin@isovalent.com
2023-04-20 16:38:10 -07:00
Alexey Dobriyan
70e79866ab ELF: fix all "Elf" typos
ELF is acronym and therefore should be spelled in all caps.

I left one exception at Documentation/arm/nwfpe/nwfpe.rst which looks like
being written in the first person.

Link: https://lkml.kernel.org/r/Y/3wGWQviIOkyLJW@p183
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-08 13:45:37 -07:00
Wei Yongjun
b24f0b049e bpftool: Set program type only if it differs from the desired one
After commit d6e6286a12 ("libbpf: disassociate section handler on explicit
bpf_program__set_type() call"), bpf_program__set_type() will force cleanup
the program's SEC() definition, this commit fixed the test helper but missed
the bpftool, which leads to bpftool prog autoattach broken as follows:

  $ bpftool prog load spi-xfer-r1v1.o /sys/fs/bpf/test autoattach
  Program spi_xfer_r1v1 does not support autoattach, falling back to pinning

This patch fix bpftool to set program type only if it differs.

Fixes: d6e6286a12 ("libbpf: disassociate section handler on explicit bpf_program__set_type() call")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230407081427.2621590-1-weiyongjun@huaweicloud.com
2023-04-07 15:28:12 -07:00
Quentin Monnet
7319296855 bpftool: Clean up _bpftool_once_attr() calls in bash completion
In bpftool's bash completion file, function _bpftool_once_attr() is able
to process multiple arguments. There are a few locations where this
function is called multiple times in a row, each time for a single
argument; let's pass all arguments instead to minimize the number of
function calls required for the completion.

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/r/20230405132120.59886-8-quentin@isovalent.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-05 21:27:27 -07:00
Quentin Monnet
7483a7a70a bpftool: Support printing opcodes and source file references in CFG
Add support for displaying opcodes or/and file references (filepath,
line and column numbers) when dumping the control flow graphs of loaded
BPF programs with bpftool.

The filepaths in the records are absolute. To avoid blocks on the graph
to get too wide, we truncate them when they get too long (but we always
keep the entire file name). In the unlikely case where the resulting
file name is ambiguous, it remains possible to get the full path with a
regular dump (no CFG).

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/r/20230405132120.59886-7-quentin@isovalent.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-05 21:27:27 -07:00
Quentin Monnet
9b79f02722 bpftool: Support "opcodes", "linum", "visual" simultaneously
When dumping a program, the keywords "opcodes" (for printing the raw
opcodes), "linum" (for displaying the filename, line number, column
number along with the source code), and "visual" (for generating the
control flow graph for translated programs) are mutually exclusive. But
there's no reason why they should be. Let's make it possible to pass
several of them at once. The "file FILE" option, which makes bpftool
output a binary image to a file, remains incompatible with the others.

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/r/20230405132120.59886-6-quentin@isovalent.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-05 21:27:27 -07:00
Quentin Monnet
05a06be722 bpftool: Return an error on prog dumps if both CFG and JSON are required
We do not support JSON output for control flow graphs of programs with
bpftool. So far, requiring both the CFG and JSON output would result in
producing a null JSON object. It makes more sense to raise an error
directly when parsing command line arguments and options, so that users
know they won't get any output they might expect.

If JSON is required for the graph, we leave it to Graphviz instead:

    # bpftool prog dump xlated <REF> visual | dot -Tjson

Suggested-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/r/20230405132120.59886-5-quentin@isovalent.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-05 21:27:27 -07:00
Quentin Monnet
9fd496848b bpftool: Support inline annotations when dumping the CFG of a program
We support dumping the control flow graph of loaded programs to the DOT
format with bpftool, but so far this feature wouldn't display the source
code lines available through BTF along with the eBPF bytecode. Let's add
support for these annotations, to make it easier to read the graph.

In prog.c, we move the call to dump_xlated_cfg() in order to pass and
use the full struct dump_data, instead of creating a minimal one in
draw_bb_node().

We pass the pointer to this struct down to dump_xlated_for_graph() in
xlated_dumper.c, where most of the logics is added. We deal with BTF
mostly like we do for plain or JSON output, except that we cannot use a
"nr_skip" value to skip a given number of linfo records (we don't
process the BPF instructions linearly, and apart from the root of the
graph we don't know how many records we should skip, so we just store
the last linfo and make sure the new one we find is different before
printing it).

When printing the source instructions to the label of a DOT graph node,
there are a few subtleties to address. We want some special newline
markers, and there are some characters that we must escape. To deal with
them, we introduce a new dedicated function btf_dump_linfo_dotlabel() in
btf_dumper.c. We'll reuse this function in a later commit to format the
filepath, line, and column references as well.

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/r/20230405132120.59886-4-quentin@isovalent.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-05 21:27:27 -07:00
Quentin Monnet
67cf52cdb6 bpftool: Fix bug for long instructions in program CFG dumps
When dumping the control flow graphs for programs using the 16-byte long
load instruction, we need to skip the second part of this instruction
when looking for the next instruction to process. Otherwise, we end up
printing "BUG_ld_00" from the kernel disassembler in the CFG.

Fixes: efcef17a6d ("tools: bpftool: generate .dot graph from CFG information")
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/r/20230405132120.59886-3-quentin@isovalent.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-05 21:27:27 -07:00
Quentin Monnet
e27f0f1620 bpftool: Fix documentation about line info display for prog dumps
The documentation states that when line_info is available when dumping a
program, the source line will be displayed "by default". There is no
notion of "default" here: the line is always displayed if available,
there is no way currently to turn it off.

In the next sentence, the documentation states that if "linum" is used
on the command line, the relevant filename, line, and column will be
displayed "on top of the source line". This is incorrect, as they are
currently displayed on the right side of the source line (or on top of
the eBPF instruction, not the source).

This commit fixes the documentation to address these points.

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/r/20230405132120.59886-2-quentin@isovalent.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-05 21:27:27 -07:00
Manu Bretelle
d8d8b00862 tools: bpftool: json: Fix backslash escape typo in jsonw_puts
This is essentially a backport of iproute2's
commit ed54f76484b5 ("json: fix backslash escape typo in jsonw_puts")

Also added the stdio.h include in json_writer.h to be able to compile
and run the json_writer test as used below).

Before this fix:

$ gcc -D notused -D TEST -I../../include -o json_writer  json_writer.c
json_writer.h
$ ./json_writer
{
    "Vyatta": {
        "url": "http://vyatta.com",
        "downloads": 2000000,
        "stock": 8.16,
        "ARGV": [],
        "empty": [],
        "NIL": {},
        "my_null": null,
        "special chars": [
            "slash": "/",
            "newline": "\n",
            "tab": "\t",
            "ff": "\f",
            "quote": "\"",
            "tick": "'",
            "backslash": "\n"
        ]
    }
}

After:

$ gcc -D notused -D TEST -I../../include -o json_writer  json_writer.c
json_writer.h
$ ./json_writer
{
    "Vyatta": {
        "url": "http://vyatta.com",
        "downloads": 2000000,
        "stock": 8.16,
        "ARGV": [],
        "empty": [],
        "NIL": {},
        "my_null": null,
        "special chars": [
            "slash": "/",
            "newline": "\n",
            "tab": "\t",
            "ff": "\f",
            "quote": "\"",
            "tick": "'",
            "backslash": "\\"
        ]
    }
}

Signed-off-by: Manu Bretelle <chantr4@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20230329073002.2026563-1-chantr4@gmail.com
2023-03-29 09:48:45 -07:00
Rong Tao
fd4cb29f2a tools/resolve_btfids: Add /libsubcmd to .gitignore
Add libsubcmd to .gitignore, otherwise after compiling the kernel it
would result in the following:

    # bpf-next...bpf-next/master
    ?? tools/bpf/resolve_btfids/libsubcmd/

Signed-off-by: Rong Tao <rongtao@cestc.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/tencent_F13D670D5D7AA9C4BD868D3220921AAC090A@qq.com
2023-03-06 16:23:01 +01:00
Luis Gerhorst
c679bbd611 tools: bpftool: Remove invalid \' json escape
RFC8259 ("The JavaScript Object Notation (JSON) Data Interchange
Format") only specifies \", \\, \/, \b, \f, \n, \r, and \r as valid
two-character escape sequences. This does not include \', which is not
required in JSON because it exclusively uses double quotes as string
separators.

Solidus (/) may be escaped, but does not have to. Only reverse
solidus (\), double quotes ("), and the control characters have to be
escaped. Therefore, with this fix, bpftool correctly supports all valid
two-character escape sequences (but still does not support characters
that require multi-character escape sequences).

Witout this fix, attempting to load a JSON file generated by bpftool
using Python 3.10.6's default json.load() may fail with the error
"Invalid \escape" if the file contains the invalid escaped single
quote (\').

Fixes: b66e907cfe ("tools: bpftool: copy JSON writer from iproute2 repository")
Signed-off-by: Luis Gerhorst <gerhorst@cs.fau.de>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20230227150853.16863-1-gerhorst@cs.fau.de
2023-02-27 11:28:16 -08:00
Ilya Leoshkevich
38f0408ef7 bpftool: Use bpf_{btf,link,map,prog}_get_info_by_fd()
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
2023-02-16 15:32:45 -08:00
Ilya Leoshkevich
585bf4640e tools: runqslower: Add EXTRA_CFLAGS and EXTRA_LDFLAGS support
This makes it possible to add sanitizer flags.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230210001210.395194-3-iii@linux.ibm.com
2023-02-10 15:21:26 -08:00
Jiri Olsa
2531ba0e4a tools/resolve_btfids: Pass HOSTCFLAGS as EXTRA_CFLAGS to prepare targets
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
2023-02-09 11:44:56 -08:00
Ian Rogers
e0975ab92f tools/resolve_btfids: Tidy HOST_OVERRIDES
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
2023-02-07 22:48:56 +01:00
Jiri Olsa
56a2df7615 tools/resolve_btfids: Compile resolve_btfids as host program
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
2023-02-07 22:47:16 +01:00
Tonghao Zhang
377c16fa3f bpftool: profile online CPUs instead of possible
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>
2023-02-02 22:20:14 -08:00
Ian Rogers
13e07691a1 tools/resolve_btfids: Alter how HOSTCC is forced
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
2023-01-25 18:28:14 +01:00
Ian Rogers
af03299d85 tools/resolve_btfids: Install subcmd headers
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
2023-01-25 18:28:08 +01:00
Holger Hoffstätte
878625e1c7 bpftool: Always disable stack protection for BPF objects
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
2023-01-13 16:44:21 +01:00
Chethan Suresh
75514e4c66 bpftool: fix output for skipping kernel config check
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>
2023-01-10 17:42:31 -08:00
James Hilliard
af0e26beaa bpftool: Add missing quotes to libbpf bootstrap submake vars
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
2023-01-10 23:12:47 +01:00
Jakub Kicinski
4aea86b403 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
No conflicts.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-05 15:34:11 -08:00
Anton Protopopov
55171f2930 bpftool: Fix linkage with statically built libllvm
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
2022-12-22 20:09:43 +01:00
Changbin Du
e7f0d5cdd0 bpf: makefiles: Do not generate empty vmlinux.h
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
2022-12-20 16:09:39 -08:00
Shen Jiamin
0e43662e61 tools/resolve_btfids: Use pkg-config to locate libelf
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
2022-12-15 22:53:10 +01:00
Miaoqian Lin
fa55ef14ef bpftool: Fix memory leak in do_build_table_cb
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
2022-12-06 21:20:42 +01:00
Sahid Orentino Ferdjaoui
52df1a8aab bpftool: remove function free_btf_vmlinux()
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>
2022-11-20 16:17:46 -08:00
Sahid Orentino Ferdjaoui
d1313e0127 bpftool: clean-up usage of libbpf_get_error()
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>
2022-11-20 16:17:46 -08:00
Sahid Orentino Ferdjaoui
d2973ffd25 bpftool: fix error message when function can't register struct_ops
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>
2022-11-20 16:17:46 -08:00
Sahid Orentino Ferdjaoui
989f285159 bpftool: replace return value PTR_ERR(NULL) with 0
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>
2022-11-20 16:17:46 -08:00
Sahid Orentino Ferdjaoui
9b81075534 bpftool: remove support of --legacy option for bpftool
Following:
  commit bd054102a8 ("libbpf: enforce strict libbpf 1.0 behaviors")
  commit 93b8952d22 ("libbpf: deprecate legacy BPF map definitions")

The --legacy option is no longer relevant as libbpf no longer supports
it. libbpf_set_strict_mode() is a no-op operation.

Signed-off-by: Sahid Orentino Ferdjaoui <sahid.ferdjaoui@industrialdiscipline.com>
Acked-by: Yonghong Song <yhs@fb.com>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/r/20221120112515.38165-2-sahid.ferdjaoui@industrialdiscipline.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-11-20 16:17:46 -08:00
Tiezhu Yang
df9c41e9db bpftool: Check argc first before "file" in do_batch()
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>
2022-11-15 21:36:24 -08:00
Jakub Kicinski
f4c4ca70de bpf-next-for-netdev
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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>
2022-11-11 18:33:04 -08:00
Jakub Kicinski
966a9b4903 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
drivers/net/can/pch_can.c
  ae64438be1 ("can: dev: fix skb drop check")
  1dd1b521be ("can: remove obsolete PCH CAN driver")
https://lore.kernel.org/all/20221110102509.1f7d63cc@canb.auug.org.au/

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-10 17:43:53 -08:00
Eduard Zingerman
c302378bc1 libbpf: Hashmap interface update to allow both long and void* keys/values
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
2022-11-09 20:45:14 -08:00
Pu Lehui
34de8e6e0e bpftool: Fix NULL pointer dereference when pin {PROG, MAP, LINK} without FILE
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
2022-11-02 12:05:42 +01:00
Colin Ian King
96f341a475 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>
2022-10-26 18:20:22 -07:00
Yonghong Song
f7f0f1657d bpftool: Support new cgroup local storage
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>
2022-10-25 23:19:19 -07:00
Quentin Monnet
08b8191ba7 bpftool: Add llvm feature to "bpftool version"
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>
2022-10-25 10:11:57 -07:00
Quentin Monnet
ce4f660862 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>
2022-10-25 10:11:56 -07:00
Quentin Monnet
eb9d1acf63 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>
2022-10-25 10:11:56 -07:00
Quentin Monnet
e1947c750f 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>
2022-10-25 10:11:56 -07:00
Quentin Monnet
2ea4d86a50 bpftool: Group libbfd defs in Makefile, only pass them if we use libbfd
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>
2022-10-25 10:11:56 -07:00