Hi Nathan, On Tue, Feb 20, 2024 at 01:44:48PM -0700, Nathan Chancellor wrote: > When building with OBJDUMP=llvm-objdump, there are a series of warnings > from the section comparisons that arch/s390/boot/Makefile performs > between vmlinux and arch/s390/boot/vmlinux: ... > It may be possible to change llvm-objdump's behavior to match GNU > objdump's behavior but the difficulty of that task has not yet been > explored. The combination of '$(OBJDUMP) -t -j' is not common in the > kernel tree on a whole, so workaround this tool difference by grepping > for the sections in the full symbol table output in a similar manner to > the sed invocation. This results in no visible change for GNU objdump > users while fixing the warnings for OBJDUMP=llvm-objdump, further > enabling use of LLVM=1 for ARCH=s390 with versions of LLVM that have > support for s390 in ld.lld and llvm-objcopy. > > Reported-by: Heiko Carstens <hca@xxxxxxxxxxxxx> > Closes: https://lore.kernel.org/20240219113248.16287-C-hca@xxxxxxxxxxxxx/ > Link: https://github.com/ClangBuiltLinux/linux/issues/859 > Signed-off-by: Nathan Chancellor <nathan@xxxxxxxxxx> > --- > s390 llvm-objcopy support may be backported to LLVM 18.1.0 in time for > the final release. > > https://github.com/llvm/llvm-project/pull/82324 > > s390 ld.lld has already made it into release/18.x: > > https://github.com/llvm/llvm-project/commit/0a44c3792a6ff799df5f100670d7e19d1bc49f03 > > If the objcopy change makes 18.1.0 final, features + this change should > build cleanly with LLVM 18.1.0+ using LLVM=1 :) > --- > arch/s390/boot/Makefile | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) This seems to work like expected (also verified with a couple of scenarios where things are supposed to break). So compiling the kernel with LLVM=1 finally works on s390! Patch applied - Thanks a lot!
