| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Wed, 4 Jul 2018 09:36:53 +0200
From: Hendrik Brueckner <brueckner@...ux.ibm.com>
To: Kim Phillips <kim.phillips@....com>
Cc: Arnaldo Carvalho de Melo <acme@...hat.com>,
Ravi Bangoria <ravi.bangoria@...ux.vnet.ibm.com>,
Alexander Shishkin <alexander.shishkin@...ux.intel.com>,
Hendrik Brueckner <brueckner@...ux.vnet.ibm.com>,
Jiri Olsa <jolsa@...hat.com>,
Michael Ellerman <mpe@...erman.id.au>,
Namhyung Kim <namhyung@...nel.org>,
Thomas Richter <tmricht@...ux.vnet.ibm.com>,
Peter Zijlstra <peterz@...radead.org>,
Ingo Molnar <mingo@...hat.com>, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 2/3] perf arm64: Generate system call table from
asm/unistd.h
Hi Kim,
On Tue, Jul 03, 2018 at 12:32:28PM -0500, Kim Phillips wrote:
> This should speed up accessing new system calls introduced with the
> kernel rather than waiting for libaudit updates to include them.
>
> Using the existing other arch scripts resulted in this error:
>
> tools/perf/arch/arm64/entry/syscalls//mksyscalltbl: 25: printf: __NR3264_ftruncate: expected numeric value
>
> because, unlike other arches, asm-generic's unistd.h does things like:
>
> #define __NR_ftruncate __NR3264_ftruncate
>
> Turning the scripts printf's %d into a %s resulted in this in the
> generated syscalls.c file:
>
> static const char *syscalltbl_arm64[] = {
> [__NR3264_ftruncate] = "ftruncate",
>
> So we use the host C compiler to fold the macros, and print them out
> from within a temporary C program, in order to get the correct output:
>
> static const char *syscalltbl_arm64[] = {
> [46] = "ftruncate",
>
> Cc: Ravi Bangoria <ravi.bangoria@...ux.vnet.ibm.com>
> Cc: Alexander Shishkin <alexander.shishkin@...ux.intel.com>
> Cc: Hendrik Brueckner <brueckner@...ux.vnet.ibm.com>
> Cc: Jiri Olsa <jolsa@...hat.com>
> Cc: Michael Ellerman <mpe@...erman.id.au>
> Cc: Namhyung Kim <namhyung@...nel.org>
> Cc: Thomas Richter <tmricht@...ux.vnet.ibm.com>
> Cc: Peter Zijlstra <peterz@...radead.org>
> Cc: Ingo Molnar <mingo@...hat.com>
> Cc: Arnaldo Carvalho de Melo <acme@...hat.com>
> Signed-off-by: Kim Phillips <kim.phillips@....com>
> ---
> tools/perf/arch/arm64/Makefile | 21 ++++++++
> .../arch/arm64/entry/syscalls/mksyscalltbl | 54 +++++++++++++++++++
> 2 files changed, 75 insertions(+)
> create mode 100755 tools/perf/arch/arm64/entry/syscalls/mksyscalltbl
>
> diff --git a/tools/perf/arch/arm64/Makefile b/tools/perf/arch/arm64/Makefile
> index 91de4860faad..85fdf4949db3 100644
> --- a/tools/perf/arch/arm64/Makefile
> +++ b/tools/perf/arch/arm64/Makefile
> @@ -4,3 +4,24 @@ PERF_HAVE_DWARF_REGS := 1
> endif
> PERF_HAVE_JITDUMP := 1
> PERF_HAVE_ARCH_REGS_QUERY_REGISTER_OFFSET := 1
> +
> +#
> +# Syscall table generation for perf
> +#
> +
> +out := $(OUTPUT)arch/arm64/include/generated/asm
> +header := $(out)/syscalls.c
> +sysdef := $(srctree)/tools/arch/arm64/include/uapi/asm/unistd.h
> +sysprf := $(srctree)/tools/perf/arch/arm64/entry/syscalls/
> +systbl := $(sysprf)/mksyscalltbl
> +
> +# Create output directory if not already present
> +_dummy := $(shell [ -d '$(out)' ] || mkdir -p '$(out)')
> +
> +$(header): $(sysdef) $(systbl)
> + $(Q)$(SHELL) '$(systbl)' '$(CC)' '$(HOSTCC)' $(sysdef) > $@
> +
> +clean::
> + $(call QUIET_CLEAN, arm64) $(RM) $(header)
> +
> +archheaders: $(header)
> diff --git a/tools/perf/arch/arm64/entry/syscalls/mksyscalltbl b/tools/perf/arch/arm64/entry/syscalls/mksyscalltbl
> new file mode 100755
> index 000000000000..1148302b7194
> --- /dev/null
> +++ b/tools/perf/arch/arm64/entry/syscalls/mksyscalltbl
> @@ -0,0 +1,54 @@
> +#!/bin/sh
> +# SPDX-License-Identifier: GPL-2.0
> +#
> +# Generate system call table for perf. Derived from
> +# powerpc script.
> +#
> +# Copyright IBM Corp. 2017
> +# Author(s): Hendrik Brueckner <brueckner@...ux.vnet.ibm.com>
> +# Changed by: Ravi Bangoria <ravi.bangoria@...ux.vnet.ibm.com>
> +# Changed by: Kim Phillips <kim.phillips@....com>
> +
> +gcc=$1
> +hostcc=$2
> +input=$3
> +
> +if ! test -r $input; then
> + echo "Could not read input file" >&2
> + exit 1
> +fi
> +
> +create_table_from_c()
> +{
> + local last_sc
For the sake of completion, also add the "sc" and "nr" local variables.
> +
> + create_table_base=`mktemp -u /tmp/create-table-XXX`
- The -u is considered to be unsafe. But from below, I think you require
this for the .c/.x file. Alternatively, you could create the file
(and prefer using more X for the template) and append to it. Or pipe
the C code to the $hostcc command, e.g.,
$hostcc -o $create_table_base -x c -
which would require a single temp file that would be overwritten by gcc.
> + echo "#include <stdio.h>" > ${create_table_base}.c
> + echo "#include \"$input\"" >> ${create_table_base}.c
> +
> + echo "int main(int argc, char *argv[])" >> ${create_table_base}.c
> + echo "{" >> ${create_table_base}.c
As alternative to these echos, use
cat >> ${create_table_base}.c <<-EoHEADER
#include <stdio.h>
#include "$input"
int main(int argc, char *argv[])
{
EoHeader
which is at least for larger portions a bit more readable.
> + while read sc nr; do
> + echo " printf(\"\\\t[%d] = \\\"$sc\\\",\\\n\", __NR_$sc);" >> ${create_table_base}.c
> + last_sc=$sc
> + done
> + echo " printf(\"#define SYSCALLTBL_ARM64_MAX_ID %d\\\n\", __NR_$last_sc);" >> ${create_table_base}.c
> + echo "}" >> ${create_table_base}.c
> +
> + $hostcc -o ${create_table_base}.x ${create_table_base}.c
> + ${create_table_base}.x
> +}
> +
> +create_table()
> +{
> + echo "static const char *syscalltbl_arm64[] = {"
> + create_table_from_c
> + echo '};'
> +
> + $RM -f ${create_table_base}.[cx]
The $RM is obtained from the (make) environment. I would prefer using rm here
to be able to run as standalone.
> +}
> +
> +$gcc -E -dM -x c $input \
> + |sed -ne 's/^#define __NR_//p' \
> + |sort -t' ' -k2 -nu \
> + |create_table
> --
> 2.17.1
>
Kind regards,
Hendrik
--
Hendrik Brueckner
brueckner@...ux.ibm.com | IBM Deutschland Research & Development GmbH
Linux on z Systems Development | Schoenaicher Str. 220, 71032 Boeblingen
IBM Deutschland Research & Development GmbH
Vorsitzender des Aufsichtsrats: Martina Koederitz
Geschaeftsfuehrung: Dirk Wittkopp
Sitz der Gesellschaft: Boeblingen
Registergericht: Amtsgericht Stuttgart, HRB 243294
Powered by blists - more mailing lists