CC'ing Alan On Thu, 22 Jun 2017 15:24:41 +1000 Stephen Rothwell <s...@canb.auug.org.au> wrote:
> Hi Dave, > > After merging almost all the trees, today's linux-next build (sparc64 > defconfig) failed like this: > > arch/sparc/lib/hweight.o: In function `__arch_hweight8': > (.text+0x0): relocation truncated to fit: R_SPARC_WDISP19 against symbol > `__sw_hweight8' defined in .text section in lib/hweight.o > arch/sparc/lib/hweight.o: In function `__arch_hweight16': > (.text+0xc): relocation truncated to fit: R_SPARC_WDISP19 against symbol > `__sw_hweight16' defined in .text section in lib/hweight.o > arch/sparc/lib/hweight.o: In function `__arch_hweight32': > (.text+0x18): relocation truncated to fit: R_SPARC_WDISP19 against symbol > `__sw_hweight32' defined in .text section in lib/hweight.o > arch/sparc/lib/hweight.o: In function `__arch_hweight64': > (.text+0x24): relocation truncated to fit: R_SPARC_WDISP19 against symbol > `__sw_hweight64' defined in .text section in lib/hweight.o After a bit of digging, this is due to that thin archives patch, but only because it changes the order of linker inputs around slightly. You can reproduce it with upstream kernel: This is the final link which succeeds: sparc64-linux-gnu-ld -m elf64_sparc --build-id -o vmlinux -T ./arch/sparc/kernel/vmlinux.lds arch/sparc/kernel/head_64.o init/built-in.o --start-group usr/built-in.o arch/sparc/built-in.o kernel/built-in.o certs/built-in.o mm/built-in.o fs/built-in.o ipc/built-in.o security/built-in.o crypto/built-in.o block/built-in.o lib/lib.a arch/sparc/prom/lib.a arch/sparc/lib/lib.a lib/built-in.o arch/sparc/prom/built-in.o arch/sparc/lib/built-in.o drivers/built-in.o sound/built-in.o firmware/built-in.o net/built-in.o virt/built-in.o --end-group .tmp_kallsyms2.o Moving the lib.a files to the end: sparc64-linux-gnu-ld -m elf64_sparc --build-id -o vmlinux -T ./arch/sparc/kernel/vmlinux.lds arch/sparc/kernel/head_64.o init/built-in.o --start-group usr/built-in.o arch/sparc/built-in.o kernel/built-in.o certs/built-in.o mm/built-in.o fs/built-in.o ipc/built-in.o security/built-in.o crypto/built-in.o block/built-in.o lib/built-in.o arch/sparc/prom/built-in.o arch/sparc/lib/built-in.o drivers/built-in.o sound/built-in.o firmware/built-in.o net/built-in.o virt/built-in.o lib/lib.a arch/sparc/prom/lib.a arch/sparc/lib/lib.a --end-group .tmp_kallsyms2.o arch/sparc/lib/lib.a(hweight.o): In function `__arch_hweight8': (.text+0x0): relocation truncated to fit: R_SPARC_WDISP19 against symbol `__sw_hweight8' defined in .text section in lib/built-in.o If we also move lib/built-in.o to the end, then the error goes away. Is there any way for the linker to place the inputs to avoid unresolvable relocations where possible? A way to work around this is to make arch/sparc/lib/hweight.o an obj-y rather than lib-y. That's a hack because it just serves to move the input location, but not really any more of a hack than the current code that also only works because of input locations... Any thoughts? Thanks, Nick
