On 9/2/2022 1:04 AM, Nick Desaulniers wrote:
On Thu, Sep 1, 2022 at 9:55 AM Nathan Chancellor <nathan@xxxxxxxxxx> wrote:
On Thu, Sep 01, 2022 at 01:52:42PM +0800, Chen, Rong A wrote:
On 9/1/2022 1:45 PM, Christophe Leroy wrote:
Le 01/09/2022 à 06:59, Chen, Rong A a écrit :
On 9/1/2022 10:03 AM, Nathan Chancellor wrote:
Hi Rong,
On Thu, Sep 01, 2022 at 09:15:58AM +0800, Chen, Rong A wrote:
On 8/31/2022 11:40 PM, Nathan Chancellor wrote:
On Wed, Aug 31, 2022 at 02:52:36PM +0800, kernel test robot wrote:
tree:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
master
head: dcf8e5633e2e69ad60b730ab5905608b756a032f
commit: f9b3cd24578401e7a392974b3353277286e49cee Kconfig.debug:
make DEBUG_INFO selectable from a choice
date: 5 months ago
config: powerpc-buildonly-randconfig-r003-20220830
(https://download.01.org/0day-ci/archive/20220831/202208311414.4OPuYS9K-lkp@xxxxxxxxx/config)
compiler: clang version 16.0.0
(https://github.com/llvm/llvm-project
c7df82e4693c19e3fd2e25c83eb04d9deb7b7b59)
reproduce (this is a W=1 build):
wget
https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# install powerpc cross compiling tool for clang build
# apt-get install binutils-powerpc-linux-gnu
#
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=f9b3cd24578401e7a392974b3353277286e49cee
git remote add linus
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
git fetch --no-tags linus master
git checkout f9b3cd24578401e7a392974b3353277286e49cee
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang
make.cross W=1 O=build_dir ARCH=powerpc SHELL=/bin/bash
If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@xxxxxxxxx>
All warnings (new ones prefixed by >>):
powerpc-linux-objdump: Warning: Unrecognized form: 0x23
Given this is clang 16.0.0 with
CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT=y, which uses DWARF5 by
default instead of DWARF4, it looks like older binutils not
understanding DWARF5. What version of binutils is being used by the
bot?
Hi Nathan,
We're using binutils v2.38.90.20220713-2
||/ Name Version Architecture Description
+++-==============-==================-============-==========================================
ii binutils 2.38.90.20220713-2 amd64 GNU assembler,
linker and binary utilities
Thanks for chiming in! This looks like the output of 'dpkg -l', right? I
Hi Nathan,
oh, yes, I misunderstood, it's not related to this package.
noticed on second glance that the tuple for the objdump warning above is
'powerpc-linux-', which leads me to believe that a kernel.org toolchain
(or a self compiled one) is being used. I would expect the tuple to be
'powerpc-linux-gnu-' if Debian's package was being used. Is that
possible?
you are right, we used a self-compiled toolchain, we'll try the binutils
from debian package.
Can you first tell us the version you are using ?
powerpc-linux-objdump -v
That will tell you the version.
Hi Christophe,
the version is v2.38:
$ ./powerpc-linux-objdump -v
GNU objdump (GNU Binutils) 2.38
Copyright (C) 2022 Free Software Foundation, Inc.
This program is free software; you may redistribute it under the terms of
the GNU General Public License version 3 or (at your option) any later
version.
This program has absolutely no warranty.
Thanks! I did some research and it seems like this warning is expected
with binutils older than 2.39. The warning appears to come from
read_and_display_attr_value() in binutils/dwarf.c. 0x22 and 0x23 are
DW_FORM_loclistx and DW_FORM_rnglistx, which were only recently
supported in that function.
https://sourceware.org/bugzilla/show_bug.cgi?id=28981
https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=19c26da69d68d5d863f37c06ad73ab6292d02ffa
That change shipped in binutils 2.39. I am not really sure how we should
work around this in the kernel, other than maybe requiring binutils
2.39+ for CONFIG_DEBUG_INFO_DWARF5. Unfortunately, that will not fix
CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT when DWARF5 is the default
version...
I've been working on a series that will encode the default implicit
dwarf version based on compiler version check. Maybe that can be
extended/reused here once that lands?
https://lore.kernel.org/llvm/20220831184408.2778264-1-ndesaulniers@xxxxxxxxxx/
Series needs revision, but it's on the right track.
Alternatively, switching to llvm-objdump for clang builds
would help :) I am not aware of any issues that would affect that switch
for PowerPC:
https://github.com/ClangBuiltLinux/linux/labels/%5BTOOL%5D%20llvm-objdump
Oh, is 0day doing `make CC=clang` rather than `make LLVM=1`? Rong,
any chance we get 0day folks to test LLVM=1 for more architectures?
Ideally we'd test both, preferably LLVM=1 if we had to choose.
Hi Nick,
Thanks for your advice, yes, we are doing `make CC=clang`, we'll plan it
recently.
Best Regards,
Rong Chen
Cheers,
Nathan
