Re: [PATCH] s390/decompresser: fix misaligned symbol build error

[Heiko Carstens]

On Thu, Jun 22, 2023 at 02:35:38PM +0000, Nathan Chancellor wrote:
> On Thu, Jun 22, 2023 at 02:55:08PM +0200, Heiko Carstens wrote:
> > Nathan Chancellor reported a kernel build error on Fedora 39:
> > 
> > $ clang --version | head -1
> > clang version 16.0.5 (Fedora 16.0.5-1.fc39)
> > 
> > $ s390x-linux-gnu-ld --version | head -1
> > GNU ld version 2.40-1.fc39
> > 
> > $ make -skj"$(nproc)" ARCH=s390 CC=clang CROSS_COMPILE=s390x-linux-gnu- olddefconfig all
> > s390x-linux-gnu-ld: arch/s390/boot/startup.o(.text+0x5b4): misaligned symbol `_decompressor_end' (0x35b0f) for relocation R_390_PC32DBL
> > make[3]: *** [.../arch/s390/boot/Makefile:78: arch/s390/boot/vmlinux] Error 1
> > 
> > It turned out that the problem with misaligned symbols on s390 was fixed
> > with commit 80ddf5ce1c92 ("s390: always build relocatable kernel") for the
> > kernel image, but did not take into account that the decompressor uses its
> > own set of CFLAGS, which come without -fPIE.
> > 
> > Add the -fPIE flag also to the decompresser CFLAGS to fix this.
> > 
> 
> I think this should also have:
> 
> Reported-by: CKI <cki-project@xxxxxxxxxx>
> Link: https://lore.kernel.org/32935.123062114500601371@xxxxxxxxxxxxxxxxxxxxxxxx/
> 
> I technically just forwarded the report and did a little extra testing.

Ok, added.

> Thanks for the quick patch, this fixes the error and I did a simple boot
> test in QEMU with the resulting kernel, which showed no issues.
> 
> Tested-by: Nathan Chancellor <nathan@xxxxxxxxxx>

And this as well. :) Thanks a lot!