[akpm-mm:mm-nonmm-unstable 49/110] __efistub_cmdline.c:undefined reference to `__efistub___lshrdi3'

[akpm-mm:mm-nonmm-unstable 49/110] __efistub_cmdline.c:undefined reference to `__efistub___lshrdi3'

[kernel test robot]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-nonmm-unstable
head:   09c4ad73ba08ac959a6afb5e019826743837e0aa
commit: 7c5bff091374a7980431237af80e6da21dce74fe [49/110] lib: fix memparse() to handle overflow
config: riscv-randconfig-001-20260304 (https://download.01.org/0day-ci/archive/20260304/202603041925.KLKqpK6N-lkp@intel.com/config)
compiler: riscv32-linux-gcc (GCC) 8.5.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260304/202603041925.KLKqpK6N-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/202603041925.KLKqpK6N-lkp@intel.com/

All errors (new ones prefixed by >>):

   riscv32-linux-ld: drivers/firmware/efi/libstub/lib-cmdline.stub.o: in function `__efistub_.L38':
>> __efistub_cmdline.c:(.init.text+0x1d4): undefined reference to `__efistub___lshrdi3'

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Re: [akpm-mm:mm-nonmm-unstable 49/110] __efistub_cmdline.c:undefined reference to `__efistub___lshrdi3'

[Andy Shevchenko]

On Wed, Mar 04, 2026 at 07:29:09PM +0800, kernel test robot wrote:
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-nonmm-unstable
> head:   09c4ad73ba08ac959a6afb5e019826743837e0aa
> commit: 7c5bff091374a7980431237af80e6da21dce74fe [49/110] lib: fix memparse() to handle overflow
> config: riscv-randconfig-001-20260304 (https://download.01.org/0day-ci/archive/20260304/202603041925.KLKqpK6N-lkp@intel.com/config)
> compiler: riscv32-linux-gcc (GCC) 8.5.0
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260304/202603041925.KLKqpK6N-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/202603041925.KLKqpK6N-lkp@intel.com/
> 
> All errors (new ones prefixed by >>):
> 
>    riscv32-linux-ld: drivers/firmware/efi/libstub/lib-cmdline.stub.o: in function `__efistub_.L38':
> >> __efistub_cmdline.c:(.init.text+0x1d4): undefined reference to `__efistub___lshrdi3'

Wow! It seems compiler tries to use some intrinsics here?
Cc'ed to more people who may be stakeholders of the efistub and overflow.

-- 
With Best Regards,
Andy Shevchenko

Re: [akpm-mm:mm-nonmm-unstable 49/110] __efistub_cmdline.c:undefined reference to `__efistub___lshrdi3'

[Andy Shevchenko]

And since it's riscv, adding people from there.

It might be that they simply need to include the corresponding library to their
architecture builds (we have lib/lshrdi3.c)

On Wed, Mar 04, 2026 at 04:12:57PM +0200, Andy Shevchenko wrote:
> On Wed, Mar 04, 2026 at 07:29:09PM +0800, kernel test robot wrote:
> > tree:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-nonmm-unstable
> > head:   09c4ad73ba08ac959a6afb5e019826743837e0aa
> > commit: 7c5bff091374a7980431237af80e6da21dce74fe [49/110] lib: fix memparse() to handle overflow
> > config: riscv-randconfig-001-20260304 (https://download.01.org/0day-ci/archive/20260304/202603041925.KLKqpK6N-lkp@intel.com/config)
> > compiler: riscv32-linux-gcc (GCC) 8.5.0
> > reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260304/202603041925.KLKqpK6N-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/202603041925.KLKqpK6N-lkp@intel.com/
> > 
> > All errors (new ones prefixed by >>):
> > 
> >    riscv32-linux-ld: drivers/firmware/efi/libstub/lib-cmdline.stub.o: in function `__efistub_.L38':
> > >> __efistub_cmdline.c:(.init.text+0x1d4): undefined reference to `__efistub___lshrdi3'
> 
> Wow! It seems compiler tries to use some intrinsics here?
> Cc'ed to more people who may be stakeholders of the efistub and overflow.

-- 
With Best Regards,
Andy Shevchenko

Re: [akpm-mm:mm-nonmm-unstable 49/110] __efistub_cmdline.c:undefined reference to `__efistub___lshrdi3'

[Ard Biesheuvel]

Hi Andy,

On Wed, 4 Mar 2026, at 15:24, Andy Shevchenko wrote:
> And since it's riscv, adding people from there.
>
> It might be that they simply need to include the corresponding library to their
> architecture builds (we have lib/lshrdi3.c)
>

I didn't manage to reproduce this, but if EFI boot on 32-bit RISC-V is really a thing, then doing the below should be sufficient. Alternatively, we might just disable EFI boot on 32-bit RISC-V, as I don't think it is likely to be used by anyone in practice.

--- a/arch/riscv/kernel/image-vars.h
+++ b/arch/riscv/kernel/image-vars.h
@@ -31,6 +31,7 @@ __efistub___init_text_end     = __init_text_end;
 #if defined(CONFIG_EFI_EARLYCON) || defined(CONFIG_SYSFB)
 __efistub_sysfb_primary_display        = sysfb_primary_display;
 #endif
+PROVIDE(__efistub___lshrdi3    = __lshrdi3);
 
 #endif