With llvm 7.0 or earlier, the map symbol type is STT_NOTYPE.
-bash-4.4$ cat t.c
__attribute__((section("maps"))) int g;
-bash-4.4$ clang -target bpf -O2 -c t.c
-bash-4.4$ readelf -s t.o
Symbol table '.symtab' contains 2 entries:
Num: Value Size Type Bind Vis Ndx Name
0: 0000000000000000 0 NOTYPE LOCAL DEFAULT UND
1: 0000000000000000 0 NOTYPE GLOBAL DEFAULT 3 g
The following llvm commit enables BPF target to generate
proper symbol type and size.
commit bf6ec206615b9718869d48b4e5400d0c6e3638dd
Author: Yonghong Song <yhs@fb.com>
Date: Wed Sep 19 16:04:13 2018 +0000
[bpf] Symbol sizes and types in object file
Clang-compiled object files currently don't include the symbol sizes and
types. Some tools however need that information. For example, ctfconvert
uses that information to generate FreeBSD's CTF representation from ELF
files.
With this patch, symbol sizes and types are included in object files.
Signed-off-by: Paul Chaignon <paul.chaignon@orange.com>
Reported-by: Yutaro Hayakawa <yhayakawa3720@gmail.com>
Hence, for llvm 8.0.0 (currently trunk), symbol type will be not NOTYPE, but OBJECT.
-bash-4.4$ clang -target bpf -O2 -c t.c
-bash-4.4$ readelf -s t.o
Symbol table '.symtab' contains 3 entries:
Num: Value Size Type Bind Vis Ndx Name
0: 0000000000000000 0 NOTYPE LOCAL DEFAULT UND
1: 0000000000000000 0 FILE LOCAL DEFAULT ABS t.c
2: 0000000000000000 4 OBJECT GLOBAL DEFAULT 3 g
This patch makes sure bpf library accepts both NOTYPE and OBJECT types
of global map symbols.
Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
|
||
|---|---|---|
| bash-completion | ||
| bridge | ||
| devlink | ||
| doc/actions | ||
| etc/iproute2 | ||
| examples | ||
| genl | ||
| include | ||
| ip | ||
| lib | ||
| man | ||
| misc | ||
| netem | ||
| rdma | ||
| schema | ||
| tc | ||
| testsuite | ||
| tipc | ||
| .gitignore | ||
| COPYING | ||
| Makefile | ||
| README | ||
| README.decnet | ||
| README.devel | ||
| README.distribution | ||
| README.iproute2+tc | ||
| README.lnstat | ||
| configure | ||
README
This is a set of utilities for Linux networking.
Information:
https://wiki.linuxfoundation.org/networking/iproute2
Download:
http://www.kernel.org/pub/linux/utils/net/iproute2/
Stable version repository:
git://git.kernel.org/pub/scm/network/iproute2/iproute2.git
Development repository:
git://git.kernel.org/pub/scm/network/iproute2/iproute2-next.git
How to compile this.
--------------------
1. libdbm
arpd needs to have the berkeleydb development libraries. For Debian
users this is the package with a name like libdbX.X-dev.
DBM_INCLUDE points to the directory with db_185.h which
is the include file used by arpd to get to the old format Berkeley
database routines. Often this is in the db-devel package.
2. make
The makefile will automatically build a config.mk file which
contains definitions of libraries that may or may not be available
on the system such as: ATM, ELF, MNL, and SELINUX.
3. To make documentation, cd to doc/ directory , then
look at start of Makefile and set correct values for
PAGESIZE=a4 , ie: a4 , letter ... (string)
PAGESPERPAGE=2 , ie: 1 , 2 ... (numeric)
and make there. It assumes, that latex, dvips and psnup
are in your path.
4. This package includes matching sanitized kernel headers because
the build environment may not have up to date versions. See Makefile
if you have special requirements and need to point at different
kernel include files.
Stephen Hemminger
stephen@networkplumber.org
Alexey Kuznetsov
kuznet@ms2.inr.ac.ru