Re: [tip:core/rseq 25/39] include/linux/rseq_entry.h:132:3: error: invalid operand for instruction

Philip Li
2025-11-25T02:28:33Z

On Mon, Nov 24, 2025 at 08:15:46PM +0100, Thomas Gleixner wrote:
> On Tue, Nov 25 2025 at 01:37, kernel test robot wrote:
> > tree: https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git core/rseq
> > head: 21782b3a5cd40892cb2995aa1ec3e74dd1112f1d
> > commit: abc850e7616c91ebaa3f5ba3617ab0a104d45039 [25/39] rseq: Provide and use rseq_update_user_cs()
> > config: powerpc-randconfig-002-20251124 (https://download.01.org/0day-ci/archive/20251125/202511250134.i0Jm8d7I-lkp@intel.com/config)
> > compiler: clang version 16.0.6 (https://github.com/llvm/llvm-project 7cbf1a2591520c2491aa35339f227775f4d3adf6)
> > reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251125/202511250134.i0Jm8d7I-lkp@intel.com/reproduce)
> >
> > If you fix the issue in a separate patch/commit (i.e. not just a new version of
> > the same patch/commit), kindly add following tags
> > | Reported-by: kernel test robot <lkp@intel.com>
> > | Closes: https://lore.kernel.org/oe-kbuild-all/202511250134.i0Jm8d7I-lkp@intel.com/
> >
> > All errors (new ones prefixed by >>):
> >
> > In file included from kernel/rseq.c:75:
> >>> include/linux/rseq_entry.h:132:3: error: invalid operand for instruction
> > unsafe_get_user(start_ip, &ucs->start_ip, efault);
> > ^
> > include/linux/uaccess.h:606:2: note: expanded from macro 'unsafe_get_user'
> > arch_unsafe_get_user(x, ptr, local_label); \
> > ^
> > arch/powerpc/include/asm/uaccess.h:458:2: note: expanded from macro 'arch_unsafe_get_user'
> > __get_user_size_goto(__gu_val, __gu_addr, sizeof(*(p)), e); \
> > ^
> > arch/powerpc/include/asm/uaccess.h:282:2: note: expanded from macro '__get_user_size_goto'
> > __get_user_size_allowed(x, ptr, size, __gus_retval); \
> > ^
> > arch/powerpc/include/asm/uaccess.h:273:10: note: expanded from macro '__get_user_size_allowed'
> > case 8: __get_user_asm2(x, (u64 __user *)ptr, retval); break; \
> > ^
> > arch/powerpc/include/asm/uaccess.h:256:4: note: expanded from macro '__get_user_asm2'
> > " li %1+1,0\n" \
> > ^
> > <inline asm>:7:5: note: instantiated into assembly here
> > li 31+1,0
>
> Definitely not a problem of tip core/rseq. It just ends up in
> __get_user_asm2() and then the compiler gets unhappy about the PowerPC
> inline assembly for whatever reason.

Thanks, got it, I will configure the bot to avoid sending further report
for this.

>
> Thanks,
>
> tglx
>
>
>