From: Eric Leblond <eric@regit•org>
To: Jesper Dangaard Brouer <brouer@redhat•com>
Cc: victor@inliniac•net, netdev@vger•kernel.org, yhs@fb•com,
Daniel Borkmann <borkmann@iogearbox•net>,
Alexei Starovoitov <alexei.starovoitov@gmail•com>
Subject: Re: [suricata PATCH 1/3] suricata/ebpf: take clang -target bpf include issue of stdint.h into account
Date: Thu, 08 Feb 2018 00:52:09 +0100 [thread overview]
Message-ID: <1518047529.18958.16.camel@regit.org> (raw)
In-Reply-To: <151804207444.30000.12666757505388007849.stgit@firesoul>
Hi,
On Wed, 2018-02-07 at 23:21 +0100, Jesper Dangaard Brouer wrote:
> From: Jesper Dangaard Brouer <netoptimizer@brouer•com>
>
> This patch prepares code before enabling the clang -target bpf.
>
> The clang compiler does not like #include <stdint.h> when
> using '-target bpf' it will fail with:
>
> fatal error: 'gnu/stubs-32.h' file not found
...
> This can be worked around by installing the 32-bit version of
> glibc-devel.i686 on your distribution.
>
> But the BPF programs does not really need to include stdint.h,
> if converting:
> uint64_t -> __u64
> uint32_t -> __u32
> uint16_t -> __u16
> uint8_t -> __u8
>
> This patch does this type syntax conversion.
There is an issue for system like Debian because they don't have a
asm/types.h in the include path if the architecture is not defined
which is the case due to target bpf. This results in:
clang-5.0 -Wall -Iinclude -O2 \
-D__KERNEL__ -D__ASM_SYSREG_H \
-target bpf -S -emit-llvm vlan_filter.c -o vlan_filter.ll
In file included from vlan_filter.c:19:
In file included from include/linux/bpf.h:11:
/usr/include/linux/types.h:5:10: fatal error: 'asm/types.h' file not
found
#include <asm/types.h>
^~~~~~~~~~~~~
1 error generated.
Makefile:523: recipe for target 'vlan_filter.bpf' failed
To go into details, the Debian package providing the 'asm/typs.h'
include is the the headers or linux-libc-dev. But this package comes
with a flavor and thus we have a prefix:
linux-libc-dev:amd64: /usr/include/x86_64-linux-gnu/asm/types.h
"Fun" part here is that if you build a debian package of the via make
in Linux tree then the linux-libc-dev package is correct.
So I propose the following patch that fixes the issue for me:
diff --git a/ebpf/Makefile.am b/ebpf/Makefile.am
index 89a3304e9..712b05343 100644
--- a/ebpf/Makefile.am
+++ b/ebpf/Makefile.am
@@ -16,6 +16,7 @@ all: $(BPF_TARGETS)
$(BPF_TARGETS): %.bpf: %.c
# From C-code to LLVM-IR format suffix .ll (clang -S -emit-llvm)
${CLANG} -Wall $(BPF_CFLAGS) -O2 \
+ -I/usr/include/$(host_cpu)-$(host_os)/ \
-D__KERNEL__ -D__ASM_SYSREG_H \
-target bpf -S -emit-llvm $< -o ${@:.bpf=.ll}
# From LLVM-IR to BPF-bytecode in ELF-obj file
Let me know if it is ok for you.
Best regards,
--
Eric Leblond <eric@regit•org>
next prev parent reply other threads:[~2018-02-07 23:52 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-02-06 14:54 [bpf-next V2 PATCH 0/5] tools/libbpf improvements and selftests Jesper Dangaard Brouer
2018-02-06 14:54 ` [bpf-next V2 PATCH 1/5] bpf: Sync kernel ABI header with tooling header for bpf_common.h Jesper Dangaard Brouer
2018-02-06 14:54 ` [bpf-next V2 PATCH 2/5] tools/libbpf: improve the pr_debug statements to contain section numbers Jesper Dangaard Brouer
2018-02-06 14:54 ` [bpf-next V2 PATCH 3/5] selftests/bpf: add test program for loading BPF ELF files Jesper Dangaard Brouer
2018-02-06 14:54 ` [bpf-next V2 PATCH 4/5] selftests/bpf: add selftest that use test_libbpf_open Jesper Dangaard Brouer
2018-02-06 14:54 ` [bpf-next V2 PATCH 5/5] tools/libbpf: handle issues with bpf ELF objects containing .eh_frames Jesper Dangaard Brouer
2018-02-06 16:00 ` Alexei Starovoitov
2018-02-06 17:03 ` Jesper Dangaard Brouer
2018-02-06 19:05 ` Daniel Borkmann
2018-02-07 12:40 ` Jesper Dangaard Brouer
2018-02-07 13:19 ` Daniel Borkmann
2018-02-07 14:58 ` Jesper Dangaard Brouer
2018-02-07 16:18 ` Daniel Borkmann
2018-02-07 22:21 ` [suricata PATCH 0/3] Suricata cleanup makefile Jesper Dangaard Brouer
2018-02-07 22:21 ` [suricata PATCH 1/3] suricata/ebpf: take clang -target bpf include issue of stdint.h into account Jesper Dangaard Brouer
2018-02-07 23:52 ` Eric Leblond [this message]
2018-02-08 8:42 ` Jesper Dangaard Brouer
2018-02-07 22:21 ` [suricata PATCH 2/3] suricata/ebpf: compile with clang -target bpf Jesper Dangaard Brouer
2018-02-07 22:21 ` [suricata PATCH 3/3] suricata/ebpf: improving the ebpf makefile Jesper Dangaard Brouer
2018-02-07 22:38 ` [suricata PATCH 0/3] Suricata cleanup makefile Eric Leblond
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1518047529.18958.16.camel@regit.org \
--to=eric@regit$(echo .)org \
--cc=alexei.starovoitov@gmail$(echo .)com \
--cc=borkmann@iogearbox$(echo .)net \
--cc=brouer@redhat$(echo .)com \
--cc=netdev@vger$(echo .)kernel.org \
--cc=victor@inliniac$(echo .)net \
--cc=yhs@fb$(echo .)com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox