Re: bootx_init.c:88: undefined reference to `__stack_chk_fail_local'

[Benjamin Herrenschmidt <benh@au1.ibm.com>]

On Tue, 2017-01-03 at 07:25 -0800, Christian Kujau wrote:
> Hi,
> 
> when compiling v4.10-rc2 with CONFIG_CC_STACKPROTECTOR_STRONG=y, the 
> linker fails with:

The way gcc implements the stack protector has some serious
incompatibilities with the way the Linux kernel uses r13, I wouldn't
even try until we sort that out...

Cheers,
Ben.
> 
> ================================
> + ld -EB -m elf32ppc -Bstatic --build-id -X -o .tmp_vmlinux1 -T 
> ./arch/powerpc/kernel/vmlinux.lds arch/powerpc/kernel/head_32.o 
> arch/powerpc/kernel/fpu.o arch/powerpc/kernel/vector.o 
> arch/powerpc/kernel/prom_init.o init/built-in.o --start-group 
> usr/built-in.o arch/powerpc/kernel/built-in.o arch/powerpc/mm/built-
> in.o 
> arch/powerpc/lib/built-in.o arch/powerpc/sysdev/built-in.o 
> arch/powerpc/platforms/built-in.o arch/powerpc/math-emu/built-in.o 
> arch/powerpc/crypto/built-in.o arch/powerpc/net/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 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
> arch/powerpc/platforms/built-in.o: In function `bootx_printf':
> /usr/local/src/linux-
> git/arch/powerpc/platforms/powermac/bootx_init.c:88: undefined
> reference to `__stack_chk_fail_local'
> arch/powerpc/platforms/built-in.o: In function
> `bootx_add_display_props':
> /usr/local/src/linux-
> git/arch/powerpc/platforms/powermac/bootx_init.c:211: undefined
> reference to `__stack_chk_fail_local'
> arch/powerpc/platforms/built-in.o: In function 
> `bootx_scan_dt_build_struct':
> /usr/local/src/linux-
> git/arch/powerpc/platforms/powermac/bootx_init.c:350: undefined
> reference to `__stack_chk_fail_local'
> arch/powerpc/platforms/built-in.o: In function `bootx_init':
> /usr/local/src/linux-
> git/arch/powerpc/platforms/powermac/bootx_init.c:596: undefined
> reference to `__stack_chk_fail_local'
> /usr/bin/ld.bfd.real: .tmp_vmlinux1: hidden symbol
> `__stack_chk_fail_local' isn't defined
> /usr/bin/ld.bfd.real: final link failed: Bad value
> ================================
> 
> 
> $ ld --version | head -1
> GNU ld (GNU Binutils for Debian) 2.25
> 
> $ gcc --version | head -1
> gcc-4.9.real (Debian 4.9.2-10) 4.9.2
> 
> 
> I'm regularly compiling userspace programs with -fstack-protector
> w/o 
> problems. I suspect it's either
> 6533b7c16ee5712041b4e324100550e02a9a5dda 
> ("powerpc: Initial stack protector (-fstack-protector) support") or 
> 902e06eb86cd62753974c249bd1dedae2825b430 ("powerpc/32: Change the
> stack 
> protector canary value per task") or both but I haven't started the 
> bisection yet.
> 
> Any other ideas?
> 
> Thanks,
> Christian.